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Posted: Tue Aug 28, 2007 6:54 pm
by ABM-CANNIBAL
So guys, what is my next option. I really want to get this running. Just to let you know that this motor was recently rebuild completly. Probably only 20-30 hours on it. It has a timbo stroker crank, cp pistons & ported by timbo. It also has a fixed decomp from wistech a few years ago.

Posted: Tue Aug 28, 2007 9:36 pm
by cannondale27
You need to do a compression test.Only other option I see is to remove motor and start with checking valve clearance etc.

Posted: Tue Aug 28, 2007 9:44 pm
by ABM-CANNIBAL
How will the compression test work if when I hold the throttle open it barely turns the motor over? What should the psi look like on a 13:1 piston?

Posted: Tue Aug 28, 2007 9:49 pm
by cannondale27
80-120psi. If motor is barely turning over it sure sounds like your decomp is stuckopen.If thats the case you will have over 200psi.Very hard on one-way bearing and starter.Do the wires get hot when your trying to crank it over?

Posted: Tue Aug 28, 2007 9:53 pm
by ABM-CANNIBAL
Which wires? Starter or battery? Not sure on either but I can check.

Posted: Tue Aug 28, 2007 9:55 pm
by cannondale27
To the starter.The big red one.Just interested to be sure it is high compression causing this slow cranking and not something else like a bad ground.

Posted: Tue Aug 28, 2007 9:59 pm
by ABM-CANNIBAL
Remember that the slow cranking is only when given throttle. It cranks fine when no throttle is given.

Posted: Tue Aug 28, 2007 10:02 pm
by cannondale27
That extra air ups the compression.

Posted: Tue Aug 28, 2007 10:07 pm
by ABM-CANNIBAL
I will check compression this week and also check the wire. What is involved in replacing the decomp. I looked for it in the atk diagrams but couldn't locate it. Is it in the head or case?

Posted: Tue Aug 28, 2007 10:15 pm
by cannondale27
Its in the head on the exhaustcam.