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trying to crank no compression

Old Aug 22, 2006 | 07:57 AM
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Default trying to crank no compression

trying to start motor for first time it was suppost to be rebuilt but 3 of the pisotns showing weak compression what could caus that
Old Aug 22, 2006 | 08:19 AM
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Default Re: trying to crank no compression

timing could be off and is leaving the valves open, double check your timing belt and make sure all the timing marks line up, if they do, than maybe somebody bullshitted you and sold you a blown motor. hope not though.
Old Aug 22, 2006 | 11:12 AM
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Default Re: trying to crank no compression

i thought all rebuilt motors had weak compression until they got broken in....i could be wrong
Old Aug 22, 2006 | 11:54 AM
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Default Re: trying to crank no compression

tried everything it wont crank over
Old Aug 22, 2006 | 11:55 AM
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Default Re: trying to crank no compression

Originally Posted by 1rude2l
i thought all rebuilt motors had weak compression until they got broken in....i could be wrong

the rings do have to seat themselves yes. but from his first post i am gathering that the motor didnt start and so he did a compression test and found low compression so thats why i suggested timing may be off.
Old Aug 22, 2006 | 12:00 PM
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Default Re: trying to crank no compression

timing
Old Aug 22, 2006 | 12:42 PM
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Default Re: trying to crank no compression

ok ill check the timing yea i was trying to crank and it wouldnt start i did a compression test and they all were low but one. one only had 30psi
Old Aug 22, 2006 | 12:45 PM
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Default Re: trying to crank no compression

Yup, your cam timing is off. Doesn't take much to lose enough compression to not start the car.
Old Aug 22, 2006 | 01:06 PM
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Default Re: trying to crank no compression

ok my friend is comming over to help me do the timing any thing else i should do to help crank a rebuilt motor thats been sitting
Old Aug 22, 2006 | 01:08 PM
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Default Re: trying to crank no compression

Make sure you did not wash the cylinder with fuel. Did you rotate the engine with the distributor disconected to build oil pressure first? Did you perform a wet test to verify if it was a ring issue? Did you perform a valve adjustment?


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