I removed the cylinder head from the motor... a lot easier to say than it actually is to do! This is a double overhead cam motor so both cams had to be removed in order to actually remove the cylinder head. Once the head was off I ran it over to the machine shop to have it checked. While the machine shop was doing their "thing" I was at home trying to figure out what was leaking gas from the carburetor assembly. There are four carbs on this engine. All four carbs are attached to a large plate that in turn connects to the air cleaner box- It almost looks like a really BIG 4 barrel carb. Each pair of carbs has a specially made "T" fitting that feeds each pair fuel. One of the "T" fittings was cracked. No big deal... just go to the local Honda Dealer and order the parts. Forget that... The "Dealer" is Downers Grove Yamaha Motorsports.. better known as DGY- They sell and service ALL the major brands of motorcycles. Do yourself and EVERYONE you know a favor- NEVER EVER DEAL WITH THEM!!!

"Headless" motor!

    So why am I so pleased with this bunch of bumbling IDIOTS? I did indeed order the parts I needed- which consisted of a new head gasket, the plastic fuel "T", and while I was at it another oil filter. Simple stuff.. pulled it up on their computer, verified the bike type and year, took my money, gave me the oil filter, and ordered the rest. Two days was the estimated waiting time, and in the mean time the machine shop returned the cylinder head and said it was "good". Two days was up, and I received a message that my parts were in at DGY... COOL! I picked up the parts and started on the carb first.. about half way through the disassembly process I noticed the new part didn't look quite right... Wrong part... too small, and the wrong diameter.. ok.. on to the head gasket.. wait a second... what the HECK is THAT?? Someone had put a 3/4" crease in the metal head gasket! Excuse my ignorance, BUT bent up head gaskets are not about to go on any motor of mine! No harm... no foul.. packaged up everything and took it back. I was told by the guy behind the desk that those were the parts I ordered, and that the head gasket "should" flatten when it's torqued down.......... After discussing our little "problem" with the parts manager I cancelled the "T" fitting and had them reorder the head gasket. Again they verified the year and make of the bike-  3 weeks later I got the new head gasket... wrong one... Told the manager at the store of the problems I was having with their parts department. I wanted a new one shipped next day air from the warehouse due to their incompetence... They would do it ONLY if I paid for it.. and not from the warehouse... I would have to wait for it to get to their store... And ... Geee.... Ummm... that "New" head gasket that you need??.... It's $10.00 MORE! I explained again about the problems they had caused me.. They just didn't give a damn. I canceled the order and had them refund my money. I don't know what they expected, but they were actually upset when I told them I was going to order somewhere else.. go figure? Oh yeah....... the oil filter??? IT WAS THE WRONG ONE TOO!

    There... my little tirade is over...now I feel much better... let's get back to the more "constructive" stuff...

    Now where was I ..... Oh yeah!.. the motor was in a million pieces all over the garage.. I decided to take the whole carb assembly into a good Honda dealer and just have them do the work. I ordered the head gasket from the same dealer. 2 days later I had the correct head gasket and reassembled the motor. Unfortunately the cracked carb part was backordered at the factory for 4 weeks... Not good, but there was a lot of work I could do on the craft in the mean time.

    First on my agenda was to attach the Poly fastener - skirt attachment strip- to the perimeter of the hull. I attached it with black 3M 5200 Sealant / Adhesive, and a stainless steel screw every four inches. I looked VERY unfinished. I had ordered a "Rub Rail" from Nell fabrication, and thought that I could make it work... It's supposed to go over bent aluminum angle.. Basically it was a MAJOR pain, and after doing one side of the craft I got disgusted, tore it off the craft, and locked the workshop door for 3 days... I had glued it in place with black 5200 adhesive... This stuff is tenacious, and will jump all the way across the workshop to "slime" you... safest bet is to lock the door for 3 days, quarantine the area, and wait for it to dry!

    I really liked the "rub rail" idea... I just didn't like the stuff I had! I ended up at the local Boat US store and found a nice screw on type vinyl rub rail... it turned out nice, and gave the edge of the craft where the skirt attaches a nice finished look and decent protection.

    While the craft was still on the saw horses I attached all the small pieces that I had neglected... drain plugs, steering, wiring, steering cables, throttle and choke cables, fuel lines, and finally the skirts!

Skirts being attached

    I masked off the whole craft and commenced sanding...... and sanding...... and More sanding.... and sanding some more... then I went out and sanded for a while..... get the idea yet??? Sanding really SUCKS! It took a week and a half of at least 8 hour days.. sometimes longer to get it to where it is today, and I could have probably spent another week.... but this is a hovercraft... Not a show car... this thing goes across sand bars... gets whacked by flying debris.... good enough I think!

    Hehehehehe.... read the above paragraph... multiply it by 2... exchange the word "sanding" with the word "painting"... well... you get the idea...

    Since I didn't have a craft to take to the April Terre Haute Races/ Hoverin I had planned to not go.. At the last minute I changed my mind. Bill Zang from Universal Hovercraft and I had a good time laughing at each other for not having our "finished" crafts with us. While eating dinner with Bill and Marquis Songer I mentioned that I needed to work out my exhaust system... Bill mentioned that he "Had a guy who does theirs!" Bill and Marquis set up an appointment with their exhaust guy.

     The craft was painted, wired, everything was hooked up.... except for non essentials..... Hehehehe.... Like carburetors!....Well you don't need carbs to install the exhaust system.

First Time on the Trailer!

    ROAD TRIP!! The first time the craft had EVER been out of the workshop, and the first time it had ever been on the trailer! I spent most of the day with Bill Zang at their exhaust guy's shop, and I did spend a little time at Universal Hovercraft too. Thanks to Bill and Marquis for their help! The Universal Hovercraft guys came through again!! This time on a non- Universal craft!!

New Exhaust- side view!

New Exhaust- back view!

    The carbs were done the same day the parts came in- right on schedule!  It took a couple of hours to finish hooking things up. I finished my throttle and choke cables, fuel lines, radiator hoses, and then double checked EVERYTHING!  I recruited Gary Jensen to help me with testing the craft. Gary, for those who don't know him, used to be a distributor for the now defunct Hovercraft Concepts "Aerocruiser" Hovercrafts. Gary is now the US Importer for the new Australian "Slider" Hovercrafts (  http://hovercraftsales.com/ ). Bright and early Sunday morning I was topping off the fluids, and doing another check of "EVERYTHING" before the big test flight. I put the key in the ignition, cranked it over and.... it started! Not necessarily a "good" thing... it was only running on 2 cylinders... the cylinders that I had replaced the head gasket on weren't running. It just started raining as Gary came into the workshop.... Hehehehe... kinda like an old horror film... The "gothic" element.....

    It's a "motor" for Pete's sake! How much can be wrong with it?? Spark?... Yep! Gas?... Yep! What else could it be?? Remember I had to remove the cams?? Well one of the cams has a slightly misaligned  "alignment"  mark that some idiot might accidentally install a couple of teeth off... if the idiot wasn't paying attention... Of course the timing marks on the crankshaft are impossible to get at with the motor in the craft. I was ready to give up for the day, but at Gary's prodding we spent the rest of the day disconnecting and pulling the engine, tearing it down, realigning the timing, and then we reinstalled the engine and reconnected everything in the craft. This time it started and ran as it should. Too late to fly now... next weekend for sure! I'm glad Gary was there to help in spite of all the work it was actually fun!

    During the following week I fixed a few little problems. The temperature gauge had been reading very high, but after some testing I recalibrated it. The nice fancy ($$$) tethered "Kill"  switch that I had bought.. worked backwards. I decided that I liked the way the switch fits on the craft and  I added a relay to reverse it's "logic".

    The first actual flight test  was the weekend after the Muscoda Hoverin.. missed another one! The good news is that the craft floats!

Watch the test flight Video !...

    The answer to your first question is.... I don't know!

    For those that have slow connections, don't like to watch videos, or just like reading- here's the written version-

    Sunday June 26,2002... With Gary Jensen in tow, the Viper on it's trailer we headed off to the nice, mostly deserted Des Plaines River. I gave Gary a quick lesson on how to use my  DV Video  equipment and digital camera while the craft sat and warmed up on the trailer. Once it hit about 160°F it was warm enough and I shut it down. I figured we would just walk it down to the water. After one flight it's time for a redesign of the ramp. The craft is longer than the ramp and hangs up badly- The ramp needs to be longer. After muscling the craft over it's pivot point we finally got it down to solid ground on it's own power. I grabbed a helmet and a life jacket- forgetting the 2 way radios, cell phone, wet suit, "real" shoes.. you know-all the common sense stuff I should have taken.

    I got into the craft, started it up, and flew down the ramp! No problem.. a little loud, but that's easily fixed with better mufflers. I flew about 1/4 mile upstream (at least I was thinking a little bit!). I had to keep backing out of the throttle to stop accelerating and finally when I was at about 2700 rpm it kept my speed at about 30 mph. I didn't want to get too far from the launch area so I slowed a little and did a 180°turn. As I slowed I came below "hump" speed, added throttle to get back over "hump" and the motor would not accelerate past about 4600 rpm. After a few tries the motor finally erupted in white smoke from the same cylinders that had the new head gasket. I shut down, and floated for a while.. Hey it floats really nice! If anyone needs Hovercraft shaped rafts let me know!.. Anyway the floating was getting old, and even though the current was taking me back towards the launch area the wind was blowing the opposite direction. Luckily I had stashed a paddle and tow rope on the craft the night before so I paddled to shore, hooked up the tow rope, and commenced dragging the craft back to the boat landing. The water is MIGHTY COLD in northern Illinois during June! Sure wish I had my wetsuit! Sure wish I had my river shoes instead of Teva sandals.. This is a really good way to find broken glass on the mud bottomed Des Plaines river! Once back to the launch ramp I pulled the craft up as far as I could and tied it off. I didn't realize exactly how cold my legs were with all the fun and excitement... Numb is the more appropriate description!

Row, row, row... er ... Pull, pull, pull your boat gently down the stream!

    There was no way we were going to lift the craft onto the trailer so in desperation I just backed the trailer into the water until the back of it was under the water. Gary and I dragged the craft as far as we could onto the trailer and then drove the trailer onto level ground. The engine had never gone above 170°F and the recording Tach says it reached a max rpm of 4680. The redline on this beast is around 11,000 rpm. Heck ... We finally got the craft tied down and drove it home.

    Needless to say I was pretty disgusted with the whole affair. I was ready to use the motor as an anchor! Calming down a bit over the next couple of days. I disassembled the entire power train except for the motor and cooling system. I decided that since I can't seem to get the thing to run properly then it's time to take it to someone who can.  ... And that is where it  is now.. The old "Throwing money at it until it runs" scenario.

    The Viper- for the whole 1/4 mile that I flew it- seemed very well balanced, responsive, and FAST! It should be a very nice craft once I have a running power plant.....  

   The last update was over 3 months ago way back in June. It's almost October now, and I'm happy to say the Viper is finally up and running.... and running well. A lot of changes have taken place since the last update.

    Last anyone heard of the Viper the motor had blown up for the second time, and I had taken it into a mechanic who was recommended by a friend. The diagnosis was rather dismal... The motor was basically irreparable. The head had been previously checked and proved to be perfectly fine. The problem wasn't the head, and turned out to be the cylinders themselves. Apparently when the donor motorcycle crashed it had been allowed to overheat enough to distort the top of the cylinders. The motor would run, but only to about 4000 rpm where the distorted cylinder would cause the head gasket to blow. The V4 Honda motors use a single casting for all four cylinders which would require complete disassembly of the motor and transmission to be able to flatten the top of the cylinders. Once flattened another mess is created. This motor is a dual overhead cam.. gear driven. Once the cylinders are flattened to the extent needed the cam timing would go out the window!

    Hard but necessary decision time... The Honda has had enough money thrown at it. The craft was ready to fly in April except for the motor problems. I decided to cut my loses and move on to a more traditional hovercraft power plant. I did some searching and came across a nice rebuilt Rotax 583 with electronics, dual 40 mm carbs, a custom tuned exhaust fabricated to fit my application, and a bunch of main jets for fine tuning. The motor is rated at 105 hp @ 7800 rpm in snowmobile mode. The tuned exhaust brings it down to 92.7 HP@ 7000 rpm with 69.5 ft lbs of torque... I have the dyno charts to back up the claim.

Just a little size difference!

    Ten hours of round trip driving to R&D Aerosports in Wausau , Wisconsin and back- I had my new motor. Every time I thought about the amount of work that had to be undone because of using the Honda motor I got depressed. Finally after a week of brooding about it I went into full blown "Sawzall attack" mode- closely followed by "assault of the 30,000 rpm grinder". A few hours later I had a usable frame... or so I thought..

    I love surprises.. not. When I tried to put my motor into the frame it would not fit! The mounting holes where correct, but the crankcase was too large to fit through the uprights. I assume what happened is that the engine frame was designed around the Rotax "Provision 4" crankcase..... mine is the "Provision 8" which is stronger and wider. More grinding, welding, and modifications.... it finally fit!

Finally in the frame.. Fan assembly too...

    While doing the change over from Honda to Rotax I made it a point to keep all the removed pieces so I could weigh them and be able to compare "running" weights of the two different power plants. I was VERY surprised once I added up all the extra components needed for the Honda to be useable on my Hovercraft.... The difference in weight between the two operating power plants was a remarkable 170 lbs! Yikes! That's a passenger worth of weight removed from the craft by just switching to the Rotax!

    The engine was finally in the frame. I reattached the the duct / fan assemblies to the frame, and installed and tensioned the HTD belt. The whole assembly dropped into place on the craft nicely. I took the opportunity to take digital photos and dimensions to send to R&D Aerosports so they could weld up my exhaust..... I put all the information up on a private website for them to view.

    I had removed all the Wiring that pertained to the Honda  except for the fuel pump. I decided to retain it due to the distance from the motor to the fuel tanks. I also retained the radiator setup that I had used for the Honda with the exception of removing the electric fan- I figured since there was no possibility of the Rotax running with out the main fan that it wasn't needed. I modified the rest of the wiring to suit the Rotax, and pre wired a starter circuit in case I decided to go with an electric starter in the future.

    Remember "Dixon's Law" way back at the beginning of this project? It never ceases to amaze me at how inept normally excellent companies can become at times....

    Weirdness.... Since I was using a 583 Rotax Snowmobile engine for power I figured I would just go with the snowmobile type K&N air filters, and the special water resistant covers that are made to fit them. I ordered the 2 filters and 2 covers from Dennis Kirk.. I've used them forever and never had a problem with them in the past, or since. The dual 40mm Mikuni carburetors have a 2 3/4" mounting flange for the filters. The week after I ordered I received a small package... the package contained only the cloth covers for the air filters, and a note inside saying that the filters themselves had been back ordered. I just threw them on a table in the workshop and forgot about them- didn't really need the filters without the exhaust system anyway. One week later I received an email telling me that my shipment was shipped via UPS. Friday afternoon UPS arrives and drops off the package. I open the package. The package contained tons of Styrofoam "peanuts", one filter, and a note that said the second filter was still backordered. I just threw it on the table in the workshop with the covers. It was too late to call. Monday afternoon I called Dennis Kirk to see what the problem was. At 4:00 pm the woman on the other end of the line told me that the final filter wasn't due for at least a month. We discussed canceling the order, but I decided to see if i could find it locally first. Tuesday morning I went to the Honda dealer and he found a single filter sitting in his warehouse out in New Jersey. I special ordered it and had to pay for it in full because of the "Special order" status. I went directly home and at 10:30 am called Dennis Kirk to cancel the order... " I'm sorry.. I can't cancel THAT order! It's already been shipped!"

    Needless to say I was not real happy after just forking over money for a third filter. The Dennis Kirk filter showed up two days later, and after installing my oil injection tank I decided it was time to attach the long awaited air filters. Imagine my surprise when I went to install the first one and the inside dimension of the filter was too small to slip onto the carbs. I checked the second one... same deal... Checked the box- clearly marked with the 2 3/4" ID dimension. The trusty tape measure said otherwise.

    Once again I was on the phone with customer service at Dennis Kirk. The woman told me that they had been having problems with K&N putting the wrong filters in the boxes, and that the filters where supposed to be hand measured before shipping them out... somebody can't read a tape measure, or doesn't understand that "ID" means "inside dimension"! I had to ship them back at my cost which was credited to my account. When I hung up the phone it rang again... It was Honda telling me my "special order" filter was in. I packaged up the Dennis Kirk filters and dropped them off at UPS on the way to the Honda dealer. Hehehehe... you know where this is going don't you???? The Honda guy hands me the air filter box.. I say wait a second- you and me are going to measure this thing.... 2 1/2".. again... just like the Dennis Kirk filters. I told the guy it was wrong. He said I was wrong, and that it was exactly what I ordered. After proving my point he stuck his tale between his legs and refunded my money. Whew... those things aren't cheap! Now all I had to do was deal with Dennis Kirk.

    After 3 weeks of monitoring  my "exhaust dimensions website" the only the "hits" I had were mine. Well??? In their defense I guess their main business is the "Ultralight" aircraft industry, and with the EAA Convention in Oshkosh happening in a few weeks I should not have expected to get the tuned pipe done in any quick fashion, BUT it would have been nice to have been told that up front. I started calling. No results. I even saw the guys up at the EAA Convention and they finally said they would do the exhaust as soon as they got home from Oshkosh. More calls two weeks after Oshkosh. Finally I was given the number of the "partner" that actually did the welding of the pipes. I got in contact with him and he finally looked at the website. After a long discussion we came to the conclusion that to do it right I should bring the Hovercraft up to Wausau for fitting, and that he would weld it while I waited... Good enough... Time for another "road trip", but at least it would be worth it to finally have a running hovercraft. I made another call to R&D and asked if they could get the air filters... no problem, and I told them to have them for me when I came for the exhaust. I finally cancelled the order I had with Dennis Kirk for the filters, and they promptly refunded the money.

    On Tuesday morning I took the long ten hour round trip to Wausau, Wisconsin. I came back with a new custom exhaust and a couple of air filters... cool! The fall Muscoda Hoverally was at the end of the week so I worked furiously to get the untested motor up and running for the event. I had originally planned on leaving for Muscoda on Friday morning, but I ran into a few problems with my new throttle linkage.... I had my wife sitting in the craft actuating the throttle to make sure the slides moved at the same time, and that the oil pump was properly aligned. I told her to give it full throttle... she already was, and the slides where only 5/8 open.. not a good thing! The really neat little billet aluminum "finger pull" throttle didn't have enough "pull" for the 40mm Mikunis. I did a little "creative" machining and managed to get a little more than 3/4 slide movement. I figured it was good enough for the first time out. At 8:00 pm Friday night I was finally ready to attempt starting the new motor- if it started I was going to Muscoda.. if not I wasn't.

Complete new engine in the craft... minus the air filters..

    Remember "Dixon's Law" way back at the beginning of this project? I never got as far as starting the engine. I spent the next half hour bailing gasoline out of the bottom of the craft. Remember the Rotax came from a snowmobile? Snowmobiles use gravity feed carburetors... Electric fuel pumps put out WAY too much pressure for the needle valves in gravity feed carbs and causes all the fuel to be forced out of the overflows. Gas EVERYWHERE! That's it.... not going to Muscoda........ That thought lasted for about 2 hours while I beat myself up for being so stupid. A glimmer of hope appeared somewhere in the dull recesses of my brain..... fuel pressure regulator...... easy, quick, a real "no brainer" to install!

    7:00 AM Saturday I was at the local "Pep Boys" auto parts store. I asked for a fuel pressure regulator that is made by Purolator.. even brought a printed sheet with me from the Internet. "Oh yeah.... We used to carry those.." And so it began... five auto parts stores later, and nothing.... I even called a couple of the local "Hot Rod" speed shops and they didn't have them. That's it.... not going to Muscoda........Wait a second..... JC Whitney might have it... a quick call and I have one waiting for me in "Will Call" The problem with JC Whitney is that they aren't even remotely close to my house, and they are not on the way to Muscoda. I'm desperate... I drive an hour and a half to get there, and then head for Muscoda.

    6:00 pm I finally arrived in Muscoda and manage to surprise a few people who were expecting me to not attend. The Viper is a big hit, but it's dinner time so I just park it, dump the trailer and go eat. No way to work on it during dark so I set up my tent , visited with old friends, and finally went to bed. Sunday morning I was up early, and drove to Mc Donalds for a quick Mc Something.... I returned to the launch area after about 15 minutes had installed the pressure regulator. I set it for 1 psi and turned on the ignition.... fuel pump came alive... slowed down a bit.... and pumped gas all over the bottom of the craft! Looking carefully I could see that one of the carbs was not leaking. The second carb was still gushing gas out of the overflows. I figured the float was probably stuck so I gave the float bowl a few taps to see if I could get it to stop spewing gas... no good.

    Remember "Dixon's Law" way back at the beginning of this project? I disassembled the offending Mikuni. Do they build  Mikuni Carburetors without needle valves??? Someone had ransacked the inside of my carb and removed the whole needle valve assembly! I don't know of a word to describe how I felt. I had worked so hard to get the craft to Muscoda, and it had been completely impossible to start the motor from the start. I drove home.

    I had ordered the right type of throttle during the previous week, and it arrived on Monday afternoon. I redid the entire throttle routing to make it smoother, and called R&D Aerosports about the missing needle valve... They can't figure it out either. They even claim that they ran the engine on the dyno using those carbs.... Don't know... He told me he would send me the parts. After the wait for the exhaust I figured I better cover my bets. I contacted the Midwest Mikuni Distributor and asked if he would sell parts to the general public... He said he would! I drove to their shop and told him of the needle valve fiasco.. I ended up buying replacements for both carbs and converted them over to the proper valves for use with an electric fuel pump. I went home, put the carbs back together, and after a few pulls of the recoil starter two things happened.... one I decided I needed an electric start... two.... It Started!!! I gotta say the motor ran perfectly.. a bit smoky because I was using premix fuel for the first tank to be sure the oil pump was primed, but perfectly just the same. I let it warm up and I checked all the radiator hoses and fittings for leaks... also took readings with an IR temperature scanner to be sure everything was warming up properly with out overheating due to an air pocket or some other problem. I shut it down, checked all the fasteners, made a minor HTD belt adjustment, and then ran it a while longer. Everything was good! I gave it a bit of throttle, and decided that with the amount of thrust that the motor produced that there was no way to safely do do any real testing on the trailer... I'd have to wait for the weekend. Amazingly enough UPS delivered a package from R&D Aerosports. The package not only contained the needle valve that I had been missing, but also an entire carb rebuild kit! Even MORE amazing.... the package arrived on Wednesday... only two days after I had called them. Pretty good service I think!

    Saturday afternoon Tom Dienhart from Milwaukee, Wisconsin called and asked what the Viper status was. Tom had witnessed the Muscoda problems and was willing to be the "chase" vehicle for testing now that the Viper was officially up and running.Tom owns a modified Neoteric Hovertrek that has a larger than normal Hirth on board. We decided to meet at my house on Sunday afternoon, and then drive to the local river. We arrived at the river in the late afternoon with my son Matt in tow. Tom off loaded his Hovertrek. After a few pulls I managed to get the Viper started, and smoothly backed it down the trailer into the water. I drove it up to the shoreline and killed the motor, and then went back and parked the trailer.

    The Viper started first pull! I turned it around and accelerated across the river. I fed in more throttle to get over "hump" speed, and ........... the motor just bogged down and refused to accelerate past 4000 rpm. The Rotax was jetted way too rich and it wouldn't run cleanly when it came on to the main jets. No big deal.. just annoying. I pulled the main jets out of the carbs and put in smaller ones... same result. Once more I was foiled! I had main jets with me, but they were all larger than the ones I currently had in the craft. The craft would accelerate to just below "hump" speed and just sit there. I managed to find a small sand bar and used it to get over hump speed a few times and the craft flew well. After playing around for about 5 miles I put the craft back on the trailer. My son Matt and I went for a 40 mile cruise in Tom's Hovertrek... it was great fun. I never had the chance to fly in a Neoteric craft before, and when Tom offered me the chance to actually pilot it I gladly accepted the offer. He sat behind me and explained how to use the "Reverse Boots". We went for a short flight. I found that using the reverse boots was second nature and had some fun playing around doing insane 1000 degree spins that were fast enough to throw your glasses off. Tom just laughed as we went back to the launch ramp and mentioned that I had as good a feel of the reverse boots as he did. I was amazed when Tom jumped out of his Hovertrek and told me to go fly it for a while by myself.... Again- Great Fun!! And a really fine craft!

    Monday I was in "Tear down the carb" mode again. This time I was leaving nothing to chance I went through each carb and tore EVERYTHING out of it and then wrote down exactly what parts where in each carb. I took the entire list to the Mikuni Distributor and told him what had happened the day before. He agreed the main jets were too large. I had done a nice chart of all the carb parts, and he graciously looked over the list to see if there where any glaring inconstancies as to what the jetting should actually be. Amazingly enough he supplies the same carbs to Hovertechnics for the motors they use on their hovercrafts. He sold me the parts to set my carbs up the same as theirs... It would be a good starting point at any rate. I bought more smaller main jets too.  Wednesday I had the carbs rejetted and after a few strenuous attempts I got the Rotax to run- did I mention I need a starter?? Hold that thought....

    The bucket from hell resides in the corner of my bedroom closet. I tried to move it and could not. It appeared that the covered 5 gallon paint bucket had somehow been glued to the floor... Yeah ... right... glued by GRAVITY! The bucket was completely full with not just pennies, but nickels, dimes, and quarters as well. Ten years worth of spare change lay in that bucket.... I started thinking.... Gee one of those nice little GPL Starters from Gary Lutke sure would look nice on the Viper! I wonder.....

    The bucket weighed 129 lbs.. no way to carry that thing. I split it up into 3 equal buckets and gave my bank a surprise visit. Hehehehe....They were overjoyed! After waiting for their machine to stop counting I was the one who was overjoyed when they told me how much money was in those buckets.... Lets just say it very easily covered the price of one of Gary's Rotax starters! The starter was ordered, and due the week before the World Hovercraft Championship races so I could be ready for the "World Cruise".

    It was testing time again! At least I still had a running craft after multiple "tests" which is certainly an improvement over the results I had with the Honda motor. Saturday afternoon I made another attempt of the local river. The guest chase vehicles during this assault were Gary Jensen flying the 2 place version of his pair of "Slider" Hovercrafts from New Zealand, and Mike Lynch with his Scat 12HP (My ex craft!).

    Again we unloaded, and again I started to fly across the river. This time the craft just slammed over hump speed without hesitation and continued to accelerate VERY quickly. I was paying very close attention to the dual EGT gauge that I had installed- the temperatures were OK, but slightly higher than I had wanted to see them. I flew around a bit and then returned to shore to swap out the main jets for slightly larger ones. Once the jets were swapped out I did a little bolt and fastener checking to be sure nothing had come loose... all was well. I fired up the Rotax and returned to the river. Better... Much better... The EGT liked the change so I got on to the business of testing.

    GEEZ! Does this thing have power!!! I can literally square off corners! No more wondering if your going to make a corner without hitting that pile of logs on the shore line... just aim the nose where you want to go and hit the throttle! Instant direction change!  No problem! 20 mph- chop the throttle... no plow... 25 mph- same thing. More testing all the way to 35mph and the worst that happens is that the craft slows down about like a speed boat when you chop the throttle.  Back to shore for more bolt and fastener checking.. still no problems. I top the tanks off with gas and then Mike , Gary, and myself all head downriver for some cruising. The craft flies very well, but with a bit of nose down attitude. I added a second gas tank, and it is most likely the culprit. We do long cruises so I'm afraid the second tank is there to stay. When I sit WAY back the trim is corrected... I need a trim elevator, ballast weight, a combination of the two perhaps? Maybe the weight of the starter will help. I could also use a flow straightener- under hard power the left side tends to lift a bit.

    The river we cruise is used by canoe outfitters, and 23 miles downstream is a large picnic area that caters food to the paddlers. The owners enjoy our company as well, and it's a nice place to stop while on the river. We usually stop, chat for a while, and fill up on candy bars and soft drinks for the return cruise up river. Today was no exception except that Gary had a passenger and he continued downriver for a bit more sightseeing while Mike and I stopped at the picnic area. I gave Mike the first ever passenger  ride in the Viper... I was still able to square off corners and I was able to do tight mid river 180 degree direction changes without ever going below "hump" speed... Mike is a 270 lb passenger, and I'm good for about another 190 lb! Cool! I again checked for loose bolts and nuts... This time not so good. There was a nut laying on the bottom of the craft. The nut had a broken bolt in it too! A little searching revealed that the broken bolt had held half of the coil to a custom bracket that I had made. I found all the washers and parts that had been attached to the bolt a put them away wheaare they could do no damage. I used some skirt ties to keep the coil in place. Nothing else was loose.

    The trip back was a bit more interesting... "Dixon's Law" will infect others in the immediate vicinity from time to time and once again it reared it's ugly head! I was taking it real easy flying back doing about 30 mph while Gary and Mike cruised a bit faster. I had no idea what my fuel mileage was going to be so I was just enjoying myself and just taking it easy. I came around a blind corner with a large gravel bar just past it. Sitting on the gravel bar was Gary, his passenger, and a partially disassembled "Slider". Gary signaled me over. It was a really good excuse to do a full power 180 and I came to a stop on the same gravel bar. Gary's craft had lost power.. no apparent reason, it just stopped running strong. We delved deeper into the problem and discovered that the gas line and tank area where very hot. We discovered that the problem was a "vapor lock" causing the fuel pump to starve. Mike Lynch came back and pulled up next to Gary and shut his craft down. It was getting late and the sun would set in another hour. We were still 19 miles from the launch ramp. Gary's craft had cooled enough to run again, and he waited for the rest of us to get started. The Viper started 2nd pull, and then Gary was jumping around signaling me to kill the engine. Mike's Scat would not start. Electric start and the battery chose this moment to die. No jumper cables either. My craft needed the battery to operate the fuel pump, and Gary has a special dry cell battery for starting his 110 hp Hirth. Mike was out of luck.

    It was dusk while Gary and I flew back to the launch ramp. The plan was to grab a spare battery out of Gary's truck and fly it back to Mike. The helpful Conservation Officer met us at the launch site and even though he new we had a problem on the river went into full blown "I gotta inspect this craft" mode... at least for Gary- who's craft had no numbers on it. He just left me alone. I even asked him if he wanted to check my craft to distract him from Gary, but he said he could see that I had conservation numbers on the side of the craft and that he was sure that I had all the legal requirements on board. Gary gave the officer his paperwork and left to get his trailer... He didn't want to chance the 2 person craft breaking down so he was going to take the 4 person craft off of the trailer and replace it with the 2 person craft. Officer "friendly" seemed to be fine with the paperwork.... until Gary started to unload the other craft from the trailer. "Friendly" swiveled his gaze to the craft coming down the trailer and said "Where's the paperwork for THAT one?"

    Gary is a dealer... He has one set of numbers that he switches from craft to craft. Those numbers had not come from the state yet, and now he technically was using 2 crafts at the same time on only one set of numbers. Some smooth talking from Gary, or possibly the enormous mosquito population on the boat ramp convinced Officer "Friendly" to be on his way. The Sun had set- you could still see, but not for much longer. Gary switched craft and left with the battery. I stayed behind with a cell phone... just in case more help was needed. I put the Viper back up on it's trailer, and I was happy that for once I had a fully functional craft to take home with me.

    My cell phone chirped that it had a message.. I guess the Verizon (Can you hear me? Good!) guy hasn't made it to this area of the world yet. Really bad cell phone reception in this area. The message was from Mike wondering what the heck was going on. I called back and had to leave a message.

    An hour later It was really dark out, and the mosquitoes must have decided to chase Officer Friendly or some other poor sole. I walked around by the river and never got bit. The cell phone rang and it was a broken up distorted Gary Jensen voice telling me that Mike and he had been flying through the dark when Mike encountered a boulder. Apparently, from the broken conversation, Mike had lost 8 "P" clips ("P" clips hold the bottom of the skirts to the hull) from his craft and a bunch of skirts. His craft was stranded on a sand bar in the middle of the river. According to Gary's GPS he was 2 miles from some friends who live on the river. I called them and told them what was going on.. I'll rephrase that... I called them 4 times and I think  I told them what was going on. The plan was to get Gary's craft into their backyard and leave it overnight. Mike's craft would spend the night on the river. I would drive over and bring them back to the ramp. While driving home at 10:00 pm we were all playing phone tag deciding on how to retrieve the crafts the next morning. They didn't need me to help. "Dixon's Law" was still working it's magic the next morning after fixing Mikes Scat when Gary's fan exploded on the river near the launch ramp.

    The World Hovercraft Championship and cruise was coming up the next weekend and Gary was VERY upset that he would not have his new craft on display at the event. I took felt bad for him and offered to fix the damage to the craft. I used to build and repair whitewater kayaks so this was a piece of cake. I really didn't need to do anything to the Viper to get it ready for the 94 mile "World Cruise" the next weekend. Thursday afternoon I got a call from GPL...

GPL: "Your starter is ready to be shipped."

Me: "Wasn't that supposed to be hereby now?"

GPL: "Well.. um.. yes! That's why I'm calling!"

Me: "Put it in a box and throw it in Gary Lutke's truck.. I'll get it from him at Terre Haute"

    No problem.. it was on it's way and I saved the shipping. If I had time at Terre Haute I would install it there. The trailer was another story. I finally finished the trailer ramp Friday afternoon and drove to Terre Haute, Indiana the next morning.

    The World Cruise involved 48 Hovercraft, and tons of media and spectators. I invited Tim Envall- one of the Australian team to come along on the cruise. The Viper would not start. I pulled until I couldn't anymore. Gary Lutke had given me my starter when I saw him earlier, but it wasn't installed yet... time for a plug change and a shot of WD40 on the wiring... it rained like crazy last night.

    New plugs seemed to do the trick and I finally had the Viper up and running. Tim and I moved the craft through the crowd of people and parked the craft for some group photos for the media. We waited in the long line of hovercrafts for our turn to launch. No problem, and the craft showed none of it's nose down tendencies.... I used my custom installed trim device..... a 25lb bag of lead shot.... good enough for the time being until I have time to make a trim wing.

    The cruise was supposed to be 90 miles.. one way. The return trip was scheduled for the next day. I'll use my wet tent as the preliminary excuse as to why I decided not to do the whole cruise- I would have had to take it down and then bring it with. As it turned out I really didn't need an excuse- I had one.... or make that 18... waiting for me 12 miles up the river.

    Tim and I flew smoothly and slowly increased our speed. We caught up to and passed the majority of the crafts on the river and we were having fun cruising in the 35mph range. We were flying over smooth water and the craft started into a high speed side to side vibration- almost like your flying across a series of small waves. Odd.... Odder still I looked back over my shoulder and saw 5 skirts flying up behind the craft! I pulled over to the nearest sand bar to see what had happened. Not good... I saw the 5 loose skirts flying behind the craft... What I didn't see was the 3 completely missing skirts, and two more missing skirt ties. 18 skirt ties had broken somewhere during our 12 mile journey. I inspected a few more, and a slight tug broke a few more. I had bought a bag of 1000 ties from Home Depot. They were supposed to be rated at 50 lb breaking strength.... as I found out- some where... some where not.

    I came prepared with extra skirts and ties. After an annoying 45 minutes of rolling around in the muddy sand the Viper was ready to fly again.  I had used up most of my spares and we decided to play it safe and return to the launch ramp. We ran a little faster on the way back and got up to 46 mph on the GPS. There was a lot of throttle left to go, but I really don't know the craft well enough to take a passenger any faster... I guess we'll call it "Scat" thinking ... I'd hate to cause an International incident by launching my Australian passenger head first across the river due to an unforeseen high speed plow in situation. ..Good news... The Poly-Fastener skirt system seems to be a success!!! With all the skirt tie breaking I did I lost a total of 3 skirts.... due to my inattention as much as anything else- according to witnesses that I had passed the skirts were all waving around back there for a long time- maybe even 5 miles. With no tension on them, and all the flapping around,  I was surprised I didn't loose a few more.

    We arrived back at the ramp and flew the Viper onto the trailer. The dragging of the skirts on the side of the trailer caused another 10 skirt ties to break. It was obvious I would need to throw out my bag of ties and replace every tie on the craft. I was "volunteered" into doing "land recovery" work during the racing and practice sessions... My little yellow Jeep was pretty darn busy! I had no time to replace them while at the event.

    Once home all the skirt ties were switched out to better quality 75 lb breaking strength, and every old tie in my workshop went in the garbage- can't accidentally use them if you don't have them!. The starter was very simple to hook up and makes life much easier... at least when the fuel pump is plugged in..... Yep... you guessed it... Got tired of hearing it run while I was testing the starter so I unplugged it... You KNOW I forgot to plug it back in! Luckily once I found my error I was able to find a good Samaritan with a set of jumper cables.

    Once again the Viper page is up to date... I do need to correct a self induced problem. I have too much thrust... never thought I would say it, but it's true. The Viper was designed as a cruising craft with a 582 Rotax.... I strayed from the plans and upped the horsepower from 64 to 92. My fault entirely and in my opinion not a design flaw.

    Basically the problem I have created is that I have so much thrust that I can literally fly the craft over the centerline and off of the cushion... While cruising at 45 mph with my wife on board I did a quick burst of full throttle and almost instantly drove off the cushion and planted the nose in the water... The Viper has VERY benign plow characteristics... I knew this and did it on purpose... just an experiment on a clam flat section of water. Even at 45 mph it just slows down- speed boat style...

    So what I have basically done is taken a perfectly good cruising craft and made into a "high speed" craft. I have discussed the problem with Michael Nell and he has given me a simple and elegant solution- It's his information so I won't be discussing what was done, only the end results once I have the time to do the changes, and after testing. I did another inadvertent test of the Poly-Fastener... High speed 45 degree turns at wide open throttle followed by a hard 180 with Gary Jensen on board... rolled off the cushion a bit , a side skirt dragged hard and hooked in the water breaking both 75 lb skirt ties.... The upper skirt held by the Poly Fastener stayed in place...... Nice! I think I came upon a good use for the product!

    It's now January 2004, and I have a lot of stuff to add.... crashing for pay (How does THAT work?), repairing crash damage, and a few really beneficial modifications. I've decided the "Viper Project" have become long enough and have decided to do individual "articles" instead. What better page to end on than page 13?

    Dixon's Law is alive and well........

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