cold compression numbers

djdarkmunk

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what should i get when checking the engine compression it seems on my 2002 srx i was getting 122 ish on all 3 cylinders when it was cold i was reeding in a another post that some one had 135 am i just low because the moter was cold the moter it self has 2200 miles.
 
All compression testers vary. If all 3 of the cylinders are testing the same and dont seem to be unusually low, I wouldnt worry about it.

A leak down test will tell you more. You are getting very close on the mileage to putting new rings in it though. I would check th O.D. of the pistons when you tear it down to see if they are in specs, if not replace pistons and rings. Run full synthetic 2 stroke oil if your not already
 
i also havea 2002 srx and it reads the same on all 3 122 to 125 and it has 6000k on it so thats good .and thats with it cold wide open throttle
 
all i did was hook up the tester to each of the cinders and gave a it a few good pulls was i doing it rong lol also if some one could answer this question 4 me its seems like i burn about 1 quarter a tank of gas about every 15 -20 minuets this cant be normal im getting about 40 miles out of a full tank blah i think its jetted rich as hell i don't wanna take it to the shop again
 
things to look for,

fuel leak

proper jetting ( and missing jets) you should have 147.5 pto and 146.3 center and mag main jets 42.5 pilots and of course the needle should be in there i have my clip on the center of the needle

your either leaking fuel really bad when its running or have something jacked up in the carbs

if no fuel leak is present anywhere refer to this thread to go through your carbs

http://www.totallyamaha.net/forums/showthread.php?t=43118
 
djdarkmunk said:
all i did was hook up the tester to each of the cinders and gave a it a few good pulls was i doing it rong lol also if some one could answer this question 4 me its seems like i burn about 1 quarter a tank of gas about every 15 -20 minuets this cant be normal im getting about 40 miles out of a full tank blah i think its jetted rich as hell i don't wanna take it to the shop again
Your going through that much gas has to be the result of a leak because if your missing a main jet or 2 I would think you'd be fouling plugs like crazy.Take the carbs off and make sure the mains are all in place and not lying in the bottom of the float bowl,I've seen it happen,and like Tom said verify you have the proper mains in there.If your actually burning that much gas it must have mains with an 1/8 inch hole in them. :dunno:
 
i thought it was crazy to get 40 miles to the tank im not to snowmobile inclined should i have the guy at my shop go thro it and take a look. don't wanna mess something up
 
with that much of a leak i would say its right after your fuel pump.. i would just dry the sled off (no snow) and put it on a dry spot like a drive way or shop floor and start it and with that much fuel leaking you should see it start dripping out the belly pan... i had a bad leak on my srx on a fitting where i tied my nos fuel supply in and didn't know it was leaking till i put it on the trailer (dry) and seen it dripping out...
 
i never was looking 4 a leek but we can drive ur sled in to ur basement with concrete Flore there was no drips present there is nothing dripping in the belly pan from what ive seen but ill take a dubble look tomorrow ive seriously put about 65 miles on the sled and burned up almost 2 tanks of gass and about 2 quarts of oil could my track to luse or something my dad told me the track was luse and i need to tighten it ?
 
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I found an article online from yamaha that the 02 viper was one of the first new designs to have a different compression in #1 than #2and#3. found this after checking mine, which was 125-149-150 dealer said good #s run it. ????
 


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