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Im riding that 77 Skidoo Olypique people, BUT ??

610 Views 10 Replies 3 Participants Last post by  gigerous
Hi everyone,

My on going saga of my 77 Skidoo Olypique 340. I finally have it running, I actually went for a little spin. And other than both of the skis pointing to the left. It was great.

It still isnt idleing all that great. I am not sure if that is just adjusting the Makuni carb or something. I imagine I have to fool around with it until it idles. Unless you guys have any other suggestions.

The reason the skis are bent, are the reason I got the machine. A guy hit it in the snow with his front end loader and bent them and cracked the front of the hood. Thats why I got it for free. He thought he toasted it. Good for me. :)

I appreciate some comments on what I should try to get it idling properly. I was using the throttle to keep it running without stalling it.


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For idle, Im sure the prob is the Carb. Check the Screw. YOu have one for adjusting the idle.
There are two screws, One air mix. Which is pretty near factory setting. Then I have the Idle screw. I had started with that all the way in and then started pulling it out. I guess I have to do small, small turns till I get it running smooth.
Try adjusting this screw when the motor is running.
If its similar to the modern mikunis the Idle screw only holds the throttle slide open. The same as if you were holding the throttle open except if you screw it in too far the Cable will become slack. Does that sled have points??
Yah. It has points, It has three adjustments on the carb. One is the throttle screw for the throttle needle and the barrel thing inside the carb that moves with that needle. You can adjust that with a nut that locks it in place where you need it. Look from the front of the skidoo down, the right hand side is the idle and the left hand side is the air mix. The center top is the throttle screw and cable thing.

P.S. I have been trying to adjust it while its running. Just it is so picky. It runs if I keep the throttle on. It just wants to die if I dont leave the throttle open a bit.

Thnx for all comments so far
One more piece of imformation needed .If you give it a shot of prime or choke(what have you ) as its trying to idle what happens?
Hmm. I have a primer push in/out thing, and I didnt ever try that. I just kept the throttle on. I will try that this weekend and fill ya in next week. Thnx for all the info. But maybe you could clue me in to if it runs better with the prime or worse. What I could do in that situation.

The theory is if it dies imediately or idles even worse then its getting too much fuel and you can go about checking all the things that cause too much fuel. If it cleans up and enjoys the extra fuel the primer gives it, then you can look at ways of tuning in more fuel.
Just thought of something else. On the modern mukinis. the gas for idle is siphoned up and out a small passage way angle drilled in the bottom of the carb bore. it can easily get partially plugged . maybe a good clean wirh compressed air would help.l
I developed another problem, damn. I was working on the machine and it doesnt run right now. I mean it sounds like only one cylinder is working. I did the old spark check. Darn, the right side cylinder (plug) looking from the front of the machine. I switch wires, plug caps, etc.. I figured out that I have a weak spark on that side. Well. Now I figure I must have a weak or ready to go coil. I am going to switch the coils around. And see if I get the weak spark on the other side. If I do, I am glad. Just get another coil. If I dont't, then I figure I need to get into the points and figure out maybe timing or cleaning them.

How am I doing for my diagnostics so far. I guess getting it idling is on hold for a bit.

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