79 Invader 340 First time out this season failure

[IraqvetUSMC]

So last winter my sled quit on me after an hour of riding. I found out the inner carb fuel bowl drain plug was very loose and the seal was blown causing it to leak fuel, however when I got around to actually figuring this out the snow was all gone for the season. So over the summer I got her running and adjusted the air screw out to compensate for the warm weather. So the other day we got 15" of snow and we haven't had crap all winter so I was pumped to get this bad boy out. Well I made it about 20ft out of the garage and buried it in a snow drift right off my drive way. I finagled it loose and spun it around. I tried to go and realized the track was not moving and the sled was smoking like a freight train and loading up. So needless to say I had to drag the thing back in the garage (back still hurts lol). I adjusted the carbs to book spec and it started up and smoked less today but it doesn't want to stay running at 6 turns out for idle so I had to screw the idle screw in a few turns. Also I noticed the exhaust is just full of oil. The oil coming out of the exhaust has created a puddle under where the sled sits and where the Y pipe is is all wet so what I also did was back the choke cable lock nuts all the way out and adjusted the cable screw in as far as it would go so that the choke had no way of being slightly open. I did notice the clutch is engaging today which it wasnt after it loaded up the other day, I am assuming that it was because the engine rpm'swere not high enough from running to rich. We may get some more snow next week and one more go around because I am ready to give up on this beast and scrap it haha.

[rminier]

 Hang in there...we got about 6" here in Delphi. My sons and I finally got out to ride a little bit for the 1st time this winter.
 In all my years of sleddin', this may have been the worst conditions I have ever ridden....unbelievably heavy, wet snow. It felt like traveling thru mud. Wednesday evening riding around the wet snow falling just created a mess on our helmet face shields....after about 30 seconds, you had to wipe the shield with your glove to be able to see.
 Sadly, a guy suffered a fatal accident about 10 miles North of me when he was going thru some fields and didn't see a ditch.....tragic.

[IraqvetUSMC]

Hey buddy how are you doing? I figured you would chime in lol. Thats sad to hear about that guy, definitely have to be careful when your out on a sled in unfamiliar territory. I know my friends who sled and ride out of town have paths that they scout out first and go slow to learn the land before riding fast. So my sled was running rich again before it died and i set it back to 1.5 turn out on the air screw in my garage and seems to be better but haven't rode it yet. Maybe you can help me on the choke settings, I undid the lock nut and screwed the choke cables in the all the way down position so as to make sure that the choke wasn't partially open causing the excessive rich smoke, I think i one the correct way as my owners/operators manual just says to adjust for slack but isn't real descriptive. Book says to turn idle out 6 but thats to low so I am going to turn back in 3 turns. both plugs have spark so its not a spark issue. Is there any other settings that might be helpful like a needle clip setting or something. I think its the right inner carb thats rich because the plug is wetter. Also thats the same snow we got wednesday that gave us 15" and we had 10ft snow drifts. People had to be rescued from their vehicles because they got stuck and snowed in.

[Interceptor398]

Where the choke cable sits on top the carb you should have 1/16 of an inch or a little more of slack so the plunger is seated unless the lever is up to choke it.  I had just set mine at 1/16 of an inch and the lever on 1/2 choke was almost to much choke but then the temp was in the 30's & 40's all weekend.

[IraqvetUSMC]

Thanks for the reply. I am assuming the 1/16 gap is between the bottom of the cable insulator to the top of the adjusting screw housing once the cable is pulled up?

[Interceptor398]

With the choke off grab the cable, it should be about 1/16 " free play before the cable moves the plunger in the carb.  This makes sure the choke is doing nothing unless you want choke.

[IraqvetUSMC]

Ok thanks. This sled is producing lots of oil coming out of the exhaust once it runs for a little bit it leaks oil after its shut off out the exhaust pipe and puddles on the floor. My  Y-pipe is pretty soaked in oil as will and has sprayed a little oil on the engine from it while it was running. Not sure what would cause this unless the injection pump is messed up and internally stuck open?

[rminier]

 Here are a couple pics that may help. In the 1st one, slide the rubber boot up on the choke cable to get it out of your way. If it's stuck, a squirt of WD-40 will free it up. 
 Now pull the cable up and down with the choke lever off. Watch the metal ferrule on the end of the cable...where the screwdriver is pointing....it should move up and down very easily at least 1/16 inch. ...absolutely as free as can be. ...If you continue to pull up on the cable you can feel when the choke plunger spring is resisting. As long as you have that free play, your choke plungers should be fully down, and not contributing to running rich.
 In the 2nd pic...that is the idle mixture screw...don't hesitate to back it out more than 2 turns counterclockwise from being lightly seated. That lets more air in at idle speed....sometimes you have to play with them...try to keep both carbs close to the same. On warmer days...say 30 degrees, I often had to back those screws out at least 2 1/4 turns. Each sled is probably slightly different.

[IraqvetUSMC]

Good pics, thanks. I had them blacked out quite a bit but then set them back to 1.5 turns out for stock and set the idle 3 turns from the seat. Sled will not stay running at 6 turns out like book says. 3 turns keeps it running. How prone our these old sleds to loading up if not cleaned out? I ask because a few times during the summer I started it for a minute to hear it run and then killed it. Wondering if the engine was loaded up and I hit to deep of snow right off the get go.

[IraqvetUSMC]

So I may have found the issue tonight. I pulled the slides out of both carbs to check the needle clip positions and when I pulled the inner slide apart I found a small wire strand of the throttle cable came uncoiled and was bunching up. I think it was causing the slide to hang open the whole time which would cause flooding of that carb I would think. Hopefully I am right on this one lol.

[IraqvetUSMC]

Ok so that was not the issue. Sled did run but the snow we got was not enough to steer the sled, it had nothing but push so I turned it around and put it back in the garage. It did eventually load up and die again. The right cylinder is flooding as the cylinder has oil gas blowing past the silicone seal the PO did on the Y pipe and the oil/gas is on the outside of the cylinder. I am assuming at this point I have something wrong with the float in the inner right carb. I ddi check engine compression and both cylinders are at 125 psi both, I am assuming that this is good compression for this old sled.

[IraqvetUSMC]

I may add that when the track is suspended off the ground the sled runs great especially at full throttle and half throttle. I can go from half to full with no hesitation, this thing flys.

[jimvw57]

disconnect your primer hse and plug it. Could be sucking fuel past the primer and causing the rich condition. Seems lik they only last about a year or so and they have problems with the plunger and check valve.

[IraqvetUSMC]

Thanks Jim. I have the carb apart and I am going to clean it thoroughly and make sure the float height is correct and I believe the book spec is 24mm. I am assuming that is the original 37 year old choke plunger on the carb so I am sure that small seal on the bottom is not very effective any more.

[IraqvetUSMC]

Jim, how do you go about plugging the choke hole after removing the cable from the carb? I could screw a cap or plug in there but since the passage is at the bottom then I don't see how you could plug it off. My plunger seal
has the indentation on inform where it sits but it's not cracked or anything