Flathead Timing Gear Failure?

Given that you mentioned it being a 59A, then it should have a bolt on gear . . . but one never knows the history of these engines.

When you pull the distributor, you'll be able to figure out what type of gear it has.
 
Well, if it's the regular 59A two bolt distributor, and a camshaft with a press on gear, the distributor will be spaced out from timing cover about 3/8".
 
It’s a 59 AB. Two bolt distributor. The service manual I have shows bolt on cam gear but doesn’t say if fiber gear. Doesn’t look to difficult. Can’t think of anything else to check that could cause low compression in all cylinders.
 
As was said earlier, try a different compression tester. ;)
Also, Make sure you hold the carb linkage open, so it
can suck plenty of air into all the cylinders as you are
testing compression.




.
 
A new compression tester is a good idea. Rule out the simple stuff first.



On a flathead a press on cam gear can slip, rarely. Not impossible. It won't skip a tooth as its a gear on gear timing unlike later chain. Or not.
 

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I’d do a leak down test, it will confirm you have good compression, leaky valves or make sure the valves are opening as you rotate the engine. Hopefully not a wiped cam.
 
I am a old foolish man that plays with engines of various types. Gar64,
Tell me about the last time the engine ran? I have never been around a engine where the cam gear went south. I would assume this makes a pretty good racket as the engine slows to a stop?? Am I missing something?
Ok for grins lets say the cam gear is gone. Cam still has lobes on it right? They move the lifters to open the valves. Would all the valves be all open? Seems like by chance one set of valves might be closed and a compression gage might read something different (maybe higher) in that cylinder? I shoudn't say any thing not a engine builder. I dont even own a compression tester other than my thumb!
Probably didnt help here. Sorry.
Regards,
Chris
 
I lost a cam gear in an SBC about 30 years ago. The engine was running perfectly as I pulled up to a stop sign. When I pushed on the gas to take off, the engine wasn't running. When I tried to start it, it made a clattering noise, but wouldn't start. When I got it home and pulled a rocker arm cover, half the pushrods were bent. When I pulled it apart, the timing gear was completely stripped of all of it's teeth. (These gears were an aluminum base with fiber teeth bonded on.)

It's probably different with a flathead with no timing chain, but I thought it was interesting that the gear stripped and I didn't even know it when it happened. It was only when I tried to restart it that I became aware of a problem.
 
Make sure the air valve in the compression tester is the correct one they are not the same as a tire valve uses. Using a standard valve doesn't work.


Ronnie
 
Something to try ,remove # one spark plug and distributor cap mark opposite no one terminal on the distributor body ,with thumb over the spark plug hole roll the starter when it comes up to # one it should blow your thumb of,.Then observe were the rotor is should be just past the mark ,if the teeth are gone it will be way of ,check your plugs I was called out for this same problem this week ,smoker oily motor Fuel contamination ,
 
I have never been around a engine where the cam gear went south. I would assume this makes a pretty good racket as the engine slows to a stop??

Back in the mid '60s I had a 52 Merc flathead in my car and I am pretty sure the cam gear failed in it. I was driving about 35 mph and all of a sudden there was a noise and the engine quit running and it sounded like the engine had no compression as it coasted to a stop. it was just pumping air out whatever valves were open and when I tried to restart it, it cranked like it had no compression, just a whirr sound. It was really a pretty quiet failure as I remember. Nothing like throwing a rod in a 352 FE engine, now that makes a racket.

At the time I was planning to repower my car with a SBF, so the failure initiated work on that conversion. I had a date with Uncle Sam, so I did not tear the flathead apart to confirm the actual failure.
 
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