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Discussion Starter · #1 ·
Searched up and down and Ive read anywhere from 280 to 410, dont know whats right.

I have a single end bleed pipe with twin 44s and pod filters all stock not an HO. had it at 410 400 ran like ****, now 380 370 still pig rich and the 10 stager doesnt seem like enough the mag side looks much richer on the plug. also the carbs are not origional to the engine did the non HOs come with 40s or 44s?

Im thinking 370 350 is gonna be the magic.

whats everyone else running on these?
 

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Discussion Starter · #2 ·
just tried 370 340 still pretty stinky rich. my clutching isn good though its shifting out at 7400 should I unload the engine some get it to 7800 then move forward with jetting or should I get the jetting right then set the clutch? also when I take off at wot it flashes to 8 very breifly then pulls at 72-7400 is this normal should it be flashing to like 8500 then pulling 7800, or should It just go to peak and hold? so much trouble to tune these sled engines lol.
 

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did the non HOs come with 40s or 44s?
The non-HO had 40s and jetting was at or below 300 like 300/270 on the '97 motor.
44s were on the HO motors and they were jetted just over 300. 340/310 on the '99 airscrew 1.75 out.

Your rpm's are bleeding off too much IMO. Hitting 8k and settling to 78 would be okay. I think 7700 was the common target for the 670 non. Good luck.
 

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Discussion Starter · #4 ·
I tried 300 330 and it feels weak but still sounds rich. went up to 320 350 looks good on the plugs and feels strong even though the rpm is the same, but it still sounds rich like its four stroking kinda got that rich gargling sound after 1/2 throttle over 7k no matter what jets are in there.

Could the clutch over loading the engine be the trouble? I think Ill back it off a few clicks and see what happens.
 

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Clutching has a big effect on the motor and rpm's. If the clutches are suspect then a rebuild of both should definitely be on your calendar. When I say "suspect", I mean if you've never had them done or you don't know if someone else has had them done then they are due.
You can make the tools you need from your onhand garage hardware or you can buy them. Not real cheap but get them torn down, cleaned up, rebuilt and functioning like new...springs, rollers, buttons, slides/shoes, cup, orings and a few other things. Sounds like a new belt is in order as well. Good luck.
Edit: Maybe no rollers on that secondary. lol
 

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Discussion Starter · #6 ·
I already went through everything the primary got new bushings and a new yellow/pink spring (shot in the dark starting point), secondary set to 17lbs, everything else looked good I just cleaned it all up and slaped it together. Belt is new dayco HPX. so I guess I should start with adjusting the clickers right, or would it be better to let some tension off the secondary? I couldnt care less if the backshift is slow.
 

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Good that you've been in the clutches already and a total rebuild is likely not necessary.
A couple things come to mind to address your rpm bleed. I didn't read that you replaced the secondary spring. A sacked out secondary spring could be the issue.
Also, your yl/pk primary is quite a departure from the stock blue/gr in start and finish rates. You might try something like blue/blue.
Last, do you have the stock helix installed?
I think your preload is high. The manual calls for 12-15 or so. I might reduce that some and see what happens. That said I run all of mine high and have zero rpm bleed.
As for clickers it's always good to test various settings for your own knowledge but I very much doubt this is your bleed issue and they will likely have no effect on that. I do all my clutch work at clicker #3 then use them to adjust for conditions.
Good luck.
 

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Discussion Starter · #8 · (Edited)
The clutching is gonna be funky compared to what u guys run because this is in a golf cart with 8:1 rear end and 17" tires so a bit different then driving a track. it was on 3 I put it to 5 after deciding taking the driven clutch off looks more difficult then I thought. revs clean now flashes 8100 holds 8 blowing the tires off. If I roll in and get some traction looks like 7900 on the tack. I cant belive how much power this thing makes when it revs I about **** myself, really surprised me.

The factory tach probly reads high so should I just leave it or would it pull harder at a little less rpm?

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Discussion Starter · #11 ·
ended up at 360 330 dropped the needles down one clip runs great. the carbs dont open quite full wot (ez go gas pedal assy only throws so far) but I dont think it really needs it with the 44s. still a bit too much rpm, even with a passenger its pulling 8k gonna try the clickers at 4 and see what happens.
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Its got a radiator from a polaris something or other and 2 fans. It runs about 150 160 under normal use here in south florida.
 

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Discussion Starter · #13 ·
I put a tach/hoir meter on there
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and it could just be the paralex/distance I see the tach from but 7800 on the doo tach corelates to 7200 on the tiny tach. gonna go back to 5 and see where my rpms are on the tiny tach.
 

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Discussion Starter · #15 ·
Im back to 5 and it looks like 7500 but its so tiny I cant really keep my eyes on it long enough to really tell. I think Ill just leave it there I dont have the balls to hold it wot for more then a few seconds anyways. Im blown away with the power this little engine cranks out, how much does the machine it comes out of weigh?
 

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Discussion Starter · #17 ·
Went to go test it again today and no sparky, swapped a spare cdi and it fired up. wonder if the new cdi will make the tach read correct. also had a bad engine to frame ground that could well be the cause of the tach teading wrong and the cdi failing.
 

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I might not discard that cdi just yet. No spark could easily have been a bad connection there or a ground issue. As for the tach I'm pretty sure it gets it's signal through the VR, not the ignition mod so maybe check the regulator ground.
 

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Discussion Starter · #20 ·
Ive got everything pretty well sorted now the tach shows bout 7900 and it reads about 200 above the tiny tach runs smooth and hauls ass. the cdi box was in fact bad which will make the first time I ever changed one and it wasnt a mis diagnosis lol.

Last porblem to sort out is it smokes like an old buick at idle, if you let it idle a few miniutes it get super loaded up and my plugs are fouling at a pretty fast rate. whats the pilot jet supposed to be on these I have the air screws all the way out to 3 turns and its still idling stinky rich. Also what oil do you guys use for the rotary valve ive got quicksilver full syn pwc oil in it, thinking maybe benol will leak into the case slower since its roughly twice the viscosity. Im running the same pwc oil at 32:1.
 
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