Jumped timing bent valves??

64ss409

Well Known Member
Supporting Member 9
I have seen a distributor gear so worn that it jumped a tooth. The cam drive gear was also very badly worn. That was on a 460 Ford about 10 years ago.
 

1958 delivery

Well Known Member
Supporting Member 2
I'll bet closing the hood and it running poorly are just a coincidence. Could be dirt in carb etc. Figure out why you don't see the timing mark
Does it start quickly, same as before and run poorly or is it harder to start now?
 

Moparboss

Well Known Member
I'll bet closing the hood and it running poorly are just a coincidence. Could be dirt in carb etc. Figure out why you don't see the timing mark
I agree, don’t think closing hood had was the cause. But the carb was a fresh rebuild 3 weeks ago. Tuning absolutely perfect. Then suddenly ran bad.
 

Don Jacks

Well Seasoned Member
Supporting Member 3
Check the voltage at the coil it should be 12v if the resister was by passed.IF it's low remove the wiring harness connecters at the firewall and check the pins for corrosion.This wouldn't be the first time that this has caused a running problem with these cars.
 

Moparboss

Well Known Member
I guess what I really need to know is do these motors bend valves if they jump timing???
If someone knows please let me know.
thanks
 

IMBVSUR?

Well Known Member
Supporting Member 2
It doesn't matter what the issue is, you are going to either take the engine to someone, or you are going to have to actually check some of the suggestions out. If you don't know how, just ask and many here will help out.
 

Tooth

Well Known Member
Supporting Member 3
The easiest way to tell if you have a bent valve is to do a leak down test on each cylinder at 100 psi. It will tell you if you have a bent exhaust valve or a bent intake valve. It’ll also tell you how good your rings are sealing up. Leak down test is much better than compression test.
Here you go Bob sale at harbor freight:woohooE8A1FCA9-0773-4011-8018-535C018353E6.jpeg
 
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32witha409

Well Known Member
Supporting Member 3
I guess what I really need to know is do these motors bend valves if they jump timing???
If someone knows please let me know.
thanks
For the most part any engine that was not designed specifically to be what is called a "Clearance Engine" where they expect a timing belt to break, you'll have interference issues between the pistons and valves if the valve timing goes off by a little. While each engine is a different beast when valve/piston clearance is concerned most will have problems.

When in doubt do a leak down check.
 

IMBVSUR?

Well Known Member
Supporting Member 2
The easiest way to tell if you have a bent valve is to do a leak down test on each cylinder at 100 psi. It will tell you if you have a bent exhaust valve or a bent intake valve. It’ll also tell you how good your rings are sealing up. Leak down test is much better than compression test.
Agreed. And if you don't have a leak down tester, simply remove all the plugs, lock the throttle open and turn the motor over by hand with your finger in each plug hole. You going to know real fast if you have a weak or dead cylinder.
 

Don Jacks

Well Seasoned Member
Supporting Member 3
If the jumped timing is caused by ignition,no,if it's the result of the cam timing jumping yes. We don't know how old/how many miles it has on it or anything about the car unless you tell us.I suggest pulling number one plug,bring the piston up to top dead center on the compression stroke and line up your timing marks.Pull the cap and see if the rotor is pointing at number one terminal on the cap.If it does,then your faiilure is in either the ignition system or the power going to it.IF the rotor does not line up,you have a mechanical issue and that could be several things.
 
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