Cam gear noise after warmup

HDowse

HDowse

Senior Member
I recently bought a 1929 standard coupe with an engine rebuilt 6 or 7 years ago and two owners ago. After warmup the cam gear is rattling. I tested it using the timing pin method described in the various threads on this topic. I plan to pull the timing cover to investigate. My question is why would this only clatter after warming up? Does it signify anything except that it rattles when warm? Ah, the joys of getting yet another car to work on...
 

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Pull the cover. You are probably going to see right away what the problem is.

Worn gear or gears, loose nut, bad spring, open her up. It’s the only way to know for sure.

I have to ask. What weight motor oil are you using? Light oil can cause different noises as the engine warms up. I’m not saying that’s the problem, just asking.

Tell us what you find. Enjoy.
 
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WHN,
It has 30 wt in it from the previous owner. I'll be changing the oil and putting in 20-50. The cover comes off this morning.
Hunt
 
HDowse said:
WHN,
It has 30 wt in it from the previous owner. I'll be changing the oil and putting in 20-50. The cover comes off this morning.
Hunt
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Good, try one bottle of the Blue STP along with the four quarts of 20w-50. I would do the oil change before taking timing cover off. You might get lucky!
 
It could be a lot of things we will only be guessing. If it did it right after the engine build it is probably to much lash between the gears. The mains have to be bore in the right location, not just close. Like every thing in a engine it has to be done right.
 
Update: I removed the cover and found that the aluminum center/fiber outer gear was loose on the cam. The nut came off with a whack with a hammer on screwdriver so it wasn't very tight. I thought I should check what would happen if I tightened the nut as best I could using that method. So I tightened it as best I could. The gear never got tight on the camshaft end and I could see, now with the gear off, the shiny aluminum where the cam and gear were rocking. I thought maybe the pins were too long for the thickness of the gear face but they are a good 1/64th short. I'll buy the standard size strengthened laminated gear and hex nut. The crank gear appears new and there was no lash when I attempted to move the cam gear against the crank gear. I'll also get a new spring and plunger. Once I get the parts and get it back together, I'll update the 'Barn. Thanks for the help.
 
The metal centered fiber gears were not one of Ford's better ideas. They have been problematic ever since. You're on the right track now.
 
HDowse said:
Update: I removed the cover and found that the aluminum center/fiber outer gear was loose on the cam. The nut came off with a whack with a hammer on screwdriver so it wasn't very tight. I thought I should check what would happen if I tightened the nut as best I could using that method. So I tightened it as best I could. The gear never got tight on the camshaft end and I could see, now with the gear off, the shiny aluminum where the cam and gear were rocking. I thought maybe the pins were too long for the thickness of the gear face but they are a good 1/64th short. I'll buy the standard size strengthened laminated gear and hex nut. The crank gear appears new and there was no lash when I attempted to move the cam gear against the crank gear. I'll also get a new spring and plunger. Once I get the parts and get it back together, I'll update the 'Barn. Thanks for the help.
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Get the wrench that lets you tighten the timing gear nut. 100 psi.
 
WHN said:
Get the wrench that lets you tighten the timing gear nut. 100 psi.
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When tightening it, someone can easily hold it with the CRANK! (REALLY!) Daves' Wife held it, while I coached him, on his BLUE TOOTH!
Once, I coached him for an HOUR & a HALF, to get his stuck head off! When someone says, "JUST POP THE HEAD OFF"---It's time for GREAT LAUGHTER!!!
Bill Tight
 
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Another update: I checked across the face of the timing gear towards the cam and found the aluminum insert was convex by a few thousandth causing it to rock on the cam face even when tight. I purchased the laminated fiber gear from Snyder's and installed it yesterday after making sure the timing marks were in the correct position on the old gear and the crank. I soaked the fiber gear in a tray of oil before installing it. I turned the crank pulley with a long screwdriver (plugs out) for semi-final adjustment and tapped the cam face pin to get the gear holes lined up just right. Then I started tightening the nut, then turned the engine with the hand, tighten, crank, tighten and got it seated. I spent the extra few bucks for the hex head cam nut...so much easier and I can use a BF 3/4 drive bar to get the 1.5" nut easily to 100#. I've just done it up tight enough now to check for secureness on the cam face. After getting the nut to 100#, I will grease the plunger and spring as well as drip more oil on the gear before it goes together.
Thanks for all the hints and help.
Hunt in finally sunny and warmish southern NH (tip to John Charlton in England).
 
Here are some shots of the work so far. One shows the difference between the plunger that was in the car and the new one just received. The more deeply grooved plunger was in the car. The second picture shows a slight depression in the end of the cam that measures 45 thousandths deep. My question is could the deeply grooved plunger have caused the depression in the cam, like a cutting tool? I plan to put in the new plunger with the lighter cross grooves after soaking it and the spring with oil.
 

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Could be possible. Good thing you are replacing. The grooves are there to get some oil in to lubricate. Your old one has some major grooves.
 
HDowse said:
I recently bought a 1929 standard coupe with an engine rebuilt 6 or 7 years ago and two owners ago. After warmup the cam gear is rattling. I tested it using the timing pin method described in the various threads on this topic. I plan to pull the timing cover to investigate. My question is why would this only clatter after warming up? Does it signify anything except that it rattles when warm? Ah, the joys of getting yet another car to work on...
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Did it sound like someone was drumming on a snare drum—or rather, on a woodblock? -

So—what was the end result? Did replacing the timing gear eliminate the noise?
 
So.....how happy do you think those fiber gear teeth were while you were torquing that nut to 100 ft-lbs?? This is a common issue- dont ever use the gear teeth and crankshaft to stop cam rotation while tightening the cam gear nut. Clamp a block or blocks to the rim of the gear and let the blocks stop the gear from rotating.

2nd thing-= you DO NOT need 100 ft-lbs on that nut. A good strong pull with a 12" wrench is plenty, or about 50 ft-lbs if ya gotta use a torque wrench. Not sure where that giant torque value came from but it's totally unnecessary. Enjoy your car!
 
ursus said:
The metal centered fiber gears were not one of Ford's better ideas. They have been problematic ever since. You're on the right track now.
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The metal center is not the original Ford design. That was an aftermarket reproduction part. Ford's gear was solid fiber.
 
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