milkyway64 said:Trying to figure out if my 454 jumped time. It is backfiring through the exhaust and will not start. Pulled the valve covers to make sure a spring hadn't broke. Looks fine. Went ahead and put it at TDC and pulled the cap. The rotor isn't pointing to number 1. Does that mean the timing chain has jumped? Is there any other tests I should be doing? What would be my next step. Thanks
as usual locating the issue will be a simple process of isolate and test,
theres some chance the timing chain has enough slack to cause that issue,
theres also the possibility the distributor gear is extremely worn,
the damper outer ring has come loose,on the hub,
the cam gear came loose,on the distributor,
the cam broke ,
the distributors excessively worn, or it moved,under the clamp on the intake manifold.
loose or mising vacuume hoses, a distributor that has no or a defective ignition advance function?
maybe you burnt a valve, or a couple worm cam lobes are partly to blame?
or a dozen other issues,like the firing order on the plug wires on the distributor cam got changed accidently,its simply a mater of eliminating potential probles by testing and verifying.
you really can,t guess you need to isolate and test.
Id start by verifying TDC on the engine,timing tab and damper all indicate true TDC, and if not WHY NOT?
if that checks out Id pull the distributor and inspect the cam gear, as the first steps in isolating the cause.
pulling the distributor cap and then MANUALLY trying to turn the crank in both directions with a long breaker bar to visually check how far the damper moves before the rotor in the distributor moves will give you some indication of any timing chain slack related issues.
the double roller cloyes timing chains tend to last longer before they wear and have excess slack
and they can be used with the stock O.E.M timing chain cover
This looks like a darn bargain
the double roller cloyes timing chains tend to last longer before they wear and have excess slack
and they can be used with the stock O.E.M timing chain cover
http://garage.grumpysperformance.com/index.php?threads/timing-tabs-and-indicators.1015/#post-49812
https://www.ebay.ca/itm/SB-Chevy-Ch...265086?hash=item2a6c66393e:g:jPgAAOSwRgJXiXxM
TRUE DOUBLE ROLLER TIMING CHAIN SETS FROM QUALITY MANUFACTURERS TEND TO BE MORE DURABLE
http://garage.grumpysperformance.com/index.php?threads/finding-top-dead-center.967/
http://garage.grumpysperformance.com/index.php?threads/timing-tabs-and-indicators.1015/
http://garage.grumpysperformance.co...rential-compression-testing.11089/#post-49407
http://garage.grumpysperformance.com/index.php?threads/distributor-gear-wear.1701/#post-4658
http://garage.grumpysperformance.co...ouble-shooting-rebuilding-hei-ignitions.2798/
http://garage.grumpysperformance.com/index.php?threads/shiming-a-distributor.251/#post-299
http://garage.grumpysperformance.com/index.php?threads/shiming-a-distributor.251/
http://garage.grumpysperformance.com/index.php?threads/how-to-pick-timing-gear-set.4548/
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