Timing Chain Jumped?
#11
Charter Member # 55
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Re: Timing Chain Jumped?
And yes, you can bend the valves if the chain jumps. Chances are you would have heard them banging though. For the engine not to start, and act like you say, its jumped a lot more than one tooth.
#14
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Re: Timing Chain Jumped?
Originally Posted by jmherbert
Sounds like low compression to me, maybe valve lash is not right, valves are being held open when should be shut.
I agree, but it was cranking normally and would start. Then died, then cranks like no compression. I adjusted the valves as follows
when exaust valve begines to open adjust intake, when intake opens and begins to close, adjust exhaust valve. I went zero lash plus 1/2 turn. Is that correct?
#17
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Re: Timing Chain Jumped?
Originally Posted by MILD THUNDER
I
when exaust valve begines to open adjust intake, when intake opens and begins to close, adjust exhaust valve. I went zero lash plus 1/2 turn. Is that correct?
when exaust valve begines to open adjust intake, when intake opens and begins to close, adjust exhaust valve. I went zero lash plus 1/2 turn. Is that correct?
1st part is correct - exhaust valve just starts to open...adjust intake.
2nd part should say = intake valve just about closed or just closed, adjust exhaust valve.
This way, you know 100% lifter is on base circle.
Goodt's way is fine also, makes it faster but harder to remember.
BTW: super easy to turn over motor is from loss of compression or no/little timing lead. Either valves open at wrong time, bent and staying open, or a sealing issue from the pistons or headgaskets, or as simple as spark plugs not being in tight enough.
Start with simple things first.
Make sure correct seat plugs are in and tight.
Then ignition timing - a very retarded ignition timing makes engine a lot easier to turn over with starter and can creat some real drivability issues.
Check compression next.
Check valve timing after.
#18
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Re: Timing Chain Jumped?
By any chance, is this motor a counter rotating engine ?
#20
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Re: Timing Chain Jumped?
Valve lash is to tight and when pumped up and hot, the vales are staying open!I would reajust your valves using a good engine book and follow it step by step,take your time and no short cuts! Why though with all the parts youve added does just this motor run bad?It sounded as if you had twins and im sure you did the valves and heads to both motors at the same time!Did you adjust the valves the same way on bothe motors?Pull the valve covers and the plugs and make sure everything lines up on tdc(#1 rockers,timing mark on pulley,look inside #1 with flash light and make sure the piston is up)tdc on #1 can fool you,@ tdc and 180 off almost look the same! Good luck!