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Problems starting and keeping it there.

926 Views 8 Replies 4 Participants Last post by  Ludwig
Its seems with the server problems, I lost my post. Here it is again

I have been posting my problems with my 77 Skidoo Olympique. I have cleaned the carb totally, check seals, new fuel filter, check for spark, new gas/oil mix @ 50:1 mix. Spark plugs gapped at factory spec of .20

I did all this, I can start the machine up and get it running sometimes, never a good idle tho, although one time I got it running with throttle help, then i tried to get it idling and lost it.

I adjusted the air mix screw to factory setting (1 1/2 turns 1/4 + or - ) and idle screw almost falling out.

I adjust 1/8 of a turn the air mix screw till engine revs higher and smoother and keep adjusting till it gets rough and then turn it back to the last good spot.

Anyways, the thing still isnt running and I am wondering what else I can do. Should I just get it back to where it was running with the throttle help and then adjust the carb inlet for throttle and thread it up/down a bit to make the throttle open a bit all the time and make it idle that way??


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Check your compresion.spray carb cleaner. around all your seals while its running to check for air leaks.If the engine suddenly raises idle while spaying the cleaner you have found your air leak.If the compession is low your rings are more than likey shot.maybe you have an ignition problem check your pionts or cdi which ever you have.Any other suggestions?

With your air screw set at 1 and 1/2 turns out, it should not even be close to falling out. Turn it all the way in and then turn it back out 1 and 1/2 turns. Also make sure you have the OEM jets installed in the carb. and that the e-clip is in the middle position on the mixture needle

Polaris is my way out - Other people just use a door.
Ill check all that out on the weekend guys. Thnx. We just got another 4 inches of snow :)

It was the Idle screw that was almost falling out not the air mix screw. I will try to borrow a compression tester and see. I just want to see what this little 340 will do. Thnx Ill keep you guys posted.

So whi is the idle screw almost falling out?
Seems like my '76 TNT 340 must be a similar engine, it calls for one turn out on each screw. If the idle screw is that far out I'd be surprised if it'd idle at all...
I have the Clymers book for our sleds. Whats your carb model? I'll try to remember to check it out.
Oh awesome. You should email me and we could talk private as well [email protected]

I will let you know what carb i have, I know its a Makuni but don't know what model. Do you know where that would show up?? I will check and get back at you. Thnx
If you are running a Mikuni carb like our 77 olympic has, the starting point i use to set the idle screw is to turn it all the way in and back it out 3 turns. This should get the sled started, but it may idle a little fast or slow, just slowly adjust from there. Also, on out olympic, when starting it cold, i have to use the primer to keep it running till it warms up a lil bit. as soon as it fires, it runs for about 5 or 10 seconds, then tries to die, i just hit the primer one time and it will fire right back up. I usually have to do this 3 or 4 times to get it going.

Polaris is my way out - Other people just use a door.
Awesome, I am finally finding people with information on the Olympique. Not to say everyone else wasn't a help. I really would like to hook up with someone for schematics or manual or scans or something. I have some stuff I found, but I would really like some of that electronically. You can email me private to talk more about it. [email protected]
My Tnt likes to have the throttle held for a bit until it warms up. I have a Tillotson carb though, so its probably not the best example. I do get a similar quick start and die, then another pump and start again.
I forgot to bring the Clymer's book home. I'll get it tomorrow. If you want to email me its [email protected]
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