110 PSI - compression! mechanic doesnt know crap!

niftyfifty · Post by **niftyfifty** » Thu Mar 16, 2006 2:45 am

I took my scooter to a mechanic, he did a compression test and says that 110psi is too low, thats why its not starting.

Thats crap right? he believes it should be around 150psi, and proceeded to tell me that compression can be lost through the crankshaft seals.

I am right arent i?, 110 psi is enough?

niftyfifty · Post by **niftyfifty** » Thu Mar 16, 2006 4:52 am

I just put new rings in it so it cant be compression.

tonrogs · Post by **tonrogs** » Thu Mar 16, 2006 8:20 am

113psi(minimum) according to the service manual. Since you just installed new rings, they havent seated yet and it should go up a bit. You should be fine with that compression.

Id take a look through the carb, blow it out with compressed air really good. Do you have a new spark plug? Did you install the piston correctly?(EX on piston facing the exhaust port?) Have you checked spark?

Post by **noiseguy** » Thu Mar 16, 2006 11:30 am

Your mechanic is wrong. 110 is fine for these.

MySpree · Post by **MySpree** » Thu Mar 16, 2006 3:17 pm

matt was running like 50 psi in his leet

hrnytrtlsgsxr · Post by **hrnytrtlsgsxr** » Thu Mar 16, 2006 4:58 pm

You need 90 psi dry to have the motor run.

darat · Post by **darat** » Thu Mar 16, 2006 5:00 pm

lol my old engine only had 50 psi i sware it did. it was so had to start..

jbarb · Post by **jbarb** » Thu Mar 16, 2006 10:20 pm

Mine was running with 60. Even did 25 mph. Starting was impossible though

DENMANSHAFFER · Post by **DENMANSHAFFER** » Sun Apr 16, 2006 10:12 pm

I HAVE TWO 86 SPREES AND BOTH HAVE COMPRESSION AROUND 90 PSI. BOTH START IMMEDIATELY AND RUN GREAT. COMPRESSION MEASUREMENT CAN VARY GREATLY ACCORDING TO HOW YOU HOOK UP THE TESTER. THE LESS CONNECTIONS THE BETTER THE READING.

mopedman · Post by **mopedman** » Mon Apr 17, 2006 2:53 am

matts was at 50 psi

darat · Post by **darat** » Mon Apr 17, 2006 7:24 am

i found that really funny it just took for ever to start.. i only had one ring...

stankyoleman · Post by **stankyoleman** » Tue Apr 18, 2006 3:37 pm

yeah my friends spree runs around just about 90, wouldnt normally know but my neighbor is a small engine/mechanical whiz and he goes crazy over stuff like this.

he just happened to have a compression tester, professional air compressor with mechanics needles attatchments to blow out carb ports, etc...

anyone else have a neighbor or friend that you mooch all their handy dandy equipment off? lol