Firing on one cylinder - Snowmobile Forum: Your #1 Snowmobile Forum

ZR600X2 · 01-31-2005, 02:57 PM

New Here I have a 98 zr 600 that has spark on both but fires on one, I checked the other threads, the jet is clean and the reed petals seem to be in good shape, I have not removed them for visual inspection but I felt them with my fingers.

Here is the rundown; I bought this sled my second 98 zr 600, for a good deal with some minor cosmetic damage. Fixed all that. It has a D&G pipe which is very loud, but I thought that was normal, while on a ride saturday my buddy thought it sounded funny, like it was only running on one cylinder, but we dismissed it due to the pipe, but I noticed it was consuming a large amount of fuel and greatly lacking power,barely making 7000 rpm and straining to hit 50 mph, but it went the whole 160 miles like that. So If anyone has any ideas please help me.

Thanks
Jay

**smallengineguy** · 01-31-2005, 03:17 PM

Do a compression test and see what it's reading.

kingmort · 01-31-2005, 08:10 PM

If the compression turns out good, try a new set of plugs.I doubt very much that's the problem, but it will definately rule 'em out.

Then you can start to diagnose from there

ZR600X2 · 02-02-2005, 12:54 AM

UPDATE:
I did a compression test, as weird as it sounds it read 120 and 115 when cold. but at operating temp it read 90 and 85 with or without the throttle open. More confusing data; it will start and run on the left (clutch side) cylinder no prob, but not on the right,unless you hold the throtthe half way, any less it dies.

I think I will start exchanging parts 1 by 1 from the good sled to mine to see what the problem is. If the carb off my wifes sled works then I need to work the carb, and so on until I find the problem(s).
Jay

Snow Freak · 02-02-2005, 06:00 PM

That is weird.. Why would the compression be that much lower when warm? Is that normal? BTW where in Maine are you? Im in Westbrook.

**smallengineguy** · 02-02-2005, 08:12 PM

How many miles on it? You might want to try spraying some carb cleaner on the crank seal while it's running to eliminate a seal leaking. Otherwise it may be time to re-ring it.

ZR600X2 · 02-04-2005, 04:30 PM

Hey snow freak I'm in St. Albans near Newport, are you familiar with that area. I took this sled for a ride from my house to Moosehead lake in Greenville 160 miles round trip.

Smallengineguy, Where exactly should I spray cleaner?

Today I synchronized the carbs and removed the head and did a visual inspection, the inside o-rings seemed to expand once I removed the so they wont go back in. lot of carbon on left (good) cylinder, very little on bad cylinder, may have some coolant leaking in by the o-ring? no scoring on the cylinders and pistons have no holes or burns. What next?????
Jay

Snow Freak · 02-04-2005, 06:04 PM

Quote:

Originally posted by ZR600X2
Hey snow freak I'm in St. Albans near Newport, are you familiar with that area. I took this sled for a ride from my house to Moosehead lake in Greenville 160 miles round trip.

I know where Newport is, we stop there when we go to Moosehead.

cgarner · 02-21-2005, 09:40 PM

I believe you spray the cab cleaner at the crank on the clutch side (between the clutch and the block) while the motor is running (BE VERY CAREFUL). If it revs higher or you can hear that second cyinder kick in, then its the seals.

By the way, if the piston rings won't go back in, its just that they aren't lined up correctly (or was this not the ring you were referring to?)

**smallengineguy** · 02-21-2005, 09:57 PM

You usually need to replace the O-rings once they are out....

Was it using coolant?