compression test? - Snowmobile Forum: Your #1 Snowmobile Forum

Ruger · 03-31-2008, 06:37 PM

thinking of buying a 1996 ski-doo formula 500 fan, its in very good shape for $750.00 compression test shows 115 left side and 107 on right side. are the numbers close enough.it runs great, but will not start up unless i pull the plugs and dump a little gas in first. the chokes seam to be working ok. i removed the chokes and they seamed to move from close to open just fine. any ideas? THANKS FOR ANY HELP.

jagermiester · 03-31-2008, 06:40 PM

How many miles?

Ruger · 03-31-2008, 06:54 PM

3300 miles, beautiful shape to.

**smallengineguy** · 03-31-2008, 07:26 PM

Compression is a tad low, should be 120 per side. Shouldn't have to pour fuel into it to start it, though. The fuel pump might be letting the fuel drop back into the tank. Are the lines going to the carbs full?

Ruger · 03-31-2008, 07:39 PM

thanks SEG. i will have to check the fuel lines after work . does the fuel pump cost alot? is 750 a good price? thanks again for any help.

jagermiester · 03-31-2008, 09:49 PM

With an 8lb difference I would be condidering at least rings. 750 doesn't sound too bad if you are mechanically inclined enuff to do your own work.