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What compression readings should I see on a 1996 SLT 780. Th ski has an SBT reman that I installed in 2006.
My readings are:
MAG = 110
CEN = 105
PTO = 115
A factory Polaris manual says I should see 120PSI to 150PSI. I have not verified accuracy of the guage but the lower reading on the CEN and 5PSI variability between cylinders has me a little concerned.
It's been running premix since installed so oiling isn't an issue. The problem I'm trying to track down is hard starting. This problem has existed for most of the time this engine has been in the ski. I've ohm'd all the stator connections in the box and they all come within the specs listed in the Clymer's manual. Specifically, to start the ski I always need to first push the start button and then after a couple of seconds open the throttle full to get it to fire. Even when using the primer, the ski will never start with the throttle in idle position.
From all I've read, a hard starting 2-stroke usually means low compression so that's why I was starting to invesigate this possibility. The carbs were rebuilt in 2006 but I do have new needles and seats to install since I didn't have those at the time. Also, new Boyesen reeds were installed in 2006 and I do not have any blowback.
I would appreciate any suggestions to track down this problem.
Thanks,
KJ
My readings are:
MAG = 110
CEN = 105
PTO = 115
A factory Polaris manual says I should see 120PSI to 150PSI. I have not verified accuracy of the guage but the lower reading on the CEN and 5PSI variability between cylinders has me a little concerned.
It's been running premix since installed so oiling isn't an issue. The problem I'm trying to track down is hard starting. This problem has existed for most of the time this engine has been in the ski. I've ohm'd all the stator connections in the box and they all come within the specs listed in the Clymer's manual. Specifically, to start the ski I always need to first push the start button and then after a couple of seconds open the throttle full to get it to fire. Even when using the primer, the ski will never start with the throttle in idle position.
From all I've read, a hard starting 2-stroke usually means low compression so that's why I was starting to invesigate this possibility. The carbs were rebuilt in 2006 but I do have new needles and seats to install since I didn't have those at the time. Also, new Boyesen reeds were installed in 2006 and I do not have any blowback.
I would appreciate any suggestions to track down this problem.
Thanks,
KJ
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