The Great Evinrude Adventure!

[Buggy]

This isn't a build thread for a car, but i thought it was appropriate in this section anyway. In October of 2012 I became the proud owner of a 1973 Evinrude RC-35-Q rotary engine snowmobile! I found it on kijiji and after a 18 hour road trip it was all mine! It was all complete and with only 1300 miles on the odo it was in near mint shape for a snowmobile. Work began right away on it getting it ready for the coming winter season. I started by looking over the whole sled and taking stock of what I had. I found out I had actually stumbled onto a bit of a rare sled. There were 150 engines made in the very first production run and 100 demonstrator sleds were built with those engines for the 1972 winter. My sled was built in 02/72 and the serial number on the engine is #150! The very last engine built on that first production run! Here's a link to a very detailed page about the production of the sled.
http://vintageomc.webs.com/theomcproduction.htm

[Buggy]

After all the research I began to try and get the sled running. I cleaned the fuel system, rebuilt the carb, and replaced the fuel pump. A lot of the components on the sled are pulled directly from the Evinrude outboard engines from that time so finding those kinds of parts isn't difficult. I then realized that the previous owner had installed the spark plug without the crush washer and the apex seals had actually hit and wore down the end of the spark plug! Luckily the apex seals seemed to be fine and the engine still made good compression. The spark plug however was another story. Only champion made a spark plug for this engine and they discontinued it sometime in the 1980's... I then turned back to kijiji and as luck would have it I found another RC-35-Q for sale for parts! I wasted no time picking it up and salvaging what I could from it including a mint condition spark plug. Time for pics!

evinrude.jpgevinrude2.jpgevinrude3.jpgevinrude4.jpgevinrude9.jpg

[Buggy]

Pics of the parts sled. There are a lot of differences between the 2 because the parts sled is of the later production run.

evinrude5.jpgevinrude6.jpgevinrude7.jpgevinrude8.jpg

[Buggy]

Anyway that's enough for tonight. I'll pick up with the story when I have some more time. Lots more to come!

[GySgtFrank]

I didn't even know Evinrude had made a rotary snowmobile. Great Find.

[djmtsu]

Might want to hit up Jess at Rotary Recycle. I think he might be able to help with parts.

[Buggy]

Evinrude designed and built their own engines for this sled. They didn't use the common Sachs engine that the other manufacturers did so getting parts is a bit difficult. Unless the guys at Rotary Recycle are into these things too I doubt they'll have parts for me.

[djmtsu]

I think you would be surprised what they have

[Buggy]

I might have to give them a shout if I need anything. It's quite possible that the internal seals and parts are similar to the Sachs engines. A friend of mine has one of the Sachs engines. I should compare the seals and bearings etc. Anyway, continuing on with the story...

After I got the parts sled I switched over the spark plugs and hit the starter. She fired right up! I took it out for a quick spin around the yard, but when I let my buddy ride it the old girl just up and died out in the yard. We towed it back in and started to figure out the issue. After trying a few things we figured out that I had a vacuum leak somewhere on the fan side of the engine. I also tried to fix my gauge lights and in doing so I shorted the wiring and the whole wiring harness melted! Apparently fuses were not thought of on these sleds... LOL! The only part of the electrical system that was fused from the factory was the cigarette lighter... Yes this sled has a cigarette lighter! It also has electric start, neutral, and reverse! Pretty advanced for 1973. I was planning on just swapping wiring harnesses from my parts sled over, but being my sled is early production the harnesses were different. I ended up going through the entire harness and repairing the damaged wires. I also had to replace the ignition switch connector and I installed a fuseable link right at the ignition solenoid. As for the vacuum leak, I found that the crank seal on that side of the engine was toast. I was going to swap seals from the parts sled engine, but again the early production issue bit me in the ass. The engines used 2 different sized seals. I was told the engine in my parts sled ran so I decided just to swap engines completely until I could track down a replacement seal. I swapped engines, but the new engine didn't even want to start! After a lot of trial and error I realized I had been taken for a ride and the parts engine was actually toast. I took it apart and found that all the side and corner seals were seized stiff in the rotor. Back to the drawing board...

[Buggy]

I then started searching for a seal and luckily I was able to find a seal that was close and I made it work. I put my old engine back together and installed it in the sled. Success! It finally ran again.... for a little while.... After a short test ride it died again. After more trial and error I found that the check valve on the pick up tube in the tank was plugged up. I cleaned it out and we were off to the races! By this time it was February and I was going ice fishing so I loaded up the sled and took it up north! I was having great fun with it there and it was working really well! Here's a pic from that weekend. I have a video too, but I don't know how to post it. Any advice on that would be appreciated... Might have to post it on youtube first.

evinruderun.jpg

[Buggy]

As I was saying I was having a great time on the sled, but I started having a little too much fun... I was ramping the sled off some snow banks and I heard a bad clunk and then the sled wouldn't move anymore.... We tilted the sled on it's side and found that the drive sprockets for the track had broke right in half and fell out! We then had to do a recovery mission with a loader tractor and we loaded it back on the truck to go home.

evinrudebroke.jpgevinruderecovery1.jpgevinruderecovery2.jpg

[Buggy]

So the sled went back to the shop and we started the repairs again. I took out the whole main drive shaft from my parts sled and installed it into my sled. After a few hours work the old Evinrude was up and running again. I also have an old Yamaha Enticer 300 twin so my girlfriend and I decided to go out for a little ride. I gave her the Yamaha and I took my Evinrude. All was well until I decided to switch and give her the Evinrude for a bit. She moved 2 feet and the sled died AGAIN! It was a PITA to get started but I eventually got it going again. I took it out for a quick spin and everything seemed good. I gave it to the girlfriend again and after 2 more feet, it died! The joys of vintage snowmobiling! Turns out I still have a vacuum leak on the fan side of the engine. This brings us to now. I want to pull the engine and smoke test it to see where the vacuum leak is. That will likely be a summer project so stay tuned for pics of the engine removal, testing, and repair!

[tweiss3]

That is an awesome find. And the fact that you are getting some great use out of it is even better.

[FC Zach]

We did have an entire snowmobile for a while in our 'parts bike' warehouse but some time ago a fellow member picked it up. Aside from the snowmobile we do have extra motors and possibly some parts (unless the pats went with the sled).

Contact Rotary Recycle, we may have something for you.
(931) 841-3158
RotaryRecycle@gmail.com

[Buggy]

Awesome! Good to know. Other than the rotor and side seals everything from my spare engine is in great shape so hopefully I won't be needing an engine anytime soon. I'll keep you guys in mind though if I ever do need anything.