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Discussion Starter · #1 ·
I am looking for info pertaining an 80-81 Blizzard 9500. I just got the sled running this past weekend. Seems to run pretty good, until it fouls the PTO side plug. Seems like it's a little sluggish picking up RPM's, but when it does it screams. I've played around with the air screw, starting at 1-1/2 turns out. I ended up bringing the air screw out even more thinking that I'm too rich at low RPM. I also dropped the needle (clip in the top notch) to try and lean it out at 1/2 to 3/4 throttle. Then it seemed like it wasn't getting enough fuel. So, I went with the second notch from the top. Not too bad, until it fouled the plug again. I failed to take notice of what size the main jets were when I had it all apart. I do have a parts carb that has a 420 main jet, but it had race pipes on it.

I've done the obvious: I cleaned the carbs, synchronized them (by eye), mixing fuel at 40:1 with Klotz Synthetic, temperature was around 25 degrees F, 2100 ft ASL.

What am I doing wrong? Any help on troubleshooting this would be greatly appreciated. Also, some specs on initial adjustments might help.
Thanks!
 

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are the plug wires and caps in good shape?
i had a sled (94 F Z) that would constantly foul one plug, it turned out to be a short in one plug wire/cap connection.
 

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Check your compression, make sure they are within 10 percent of each other. Also check your jet #s Under normal conditions pto should be 10-20 numbers less
 

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Discussion Starter · #4 ·
sledheaded said:
Check your compression, make sure they are within 10 percent of each other. Also check your jet #s Under normal conditions pto should be 10-20 numbers less
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Compression is not within 10 percent. I think it's 150-115. Also, if I have the mag & PTO carbs mixed up, will that cause it?
 

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You need a ring in the lower comp piston at least. Changing carbs-check your jets
 

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150 compresion seems a bit high for a stock motor. 115 compresion will still run fine. what i dont like is the large difference between both cylinders.
 

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Like I said, it has to be within 10% you have to fix one cyl. at least to make it run good.
 
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