VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Camshaft timing gear.

When I rebuilt my forty's engine I got some bad advice. I put in an aluminum camshaft gear. Now my once quiet running car sounds like a diesel on any acceleration. I want a fiber gear back on the camshaft. I only have about 1500 miles on the motor. Do I have to change the crank gear too? Any experiences?

First I want to say that I am not a fan of aluminum timing gears. If getting the right amount of oil the fiber dears will last for ever.

That being said if the aluminum is getting oil they will make for a little noise if any except when the oil is cold and gear is running dry,
I suspect the aluminum gear my not be the problem..

If it we mine I would replace both gears and make sure ttthe oil passge behind the front mounting plate is allowing oil to rt to the gears.

If it makes any difference in the analysis, the motor is quiet while decelerating or planing. The block was also baked in the machine shop prior to cleaning. It looked like it just came out of the mold. Prior to overhaul it was whisper quiet on the timing gears. Could an additive to to oil be worth the trouble? I change the 10w 30 oil once a year at 500 miles.

By the way, its a 1950 216 block in my '40. I understand the oil passage was enlarged in that block.

Yes, the 1950 was improved in that area - just took longer to plug up.
Also the actual fiting could plugged up.

You could try an addditive with a high zinc content, doubt if it would help but worth a try.

Hi Rog40

As Gene said above...

I don't think the aluminum gear is your problem.

In fact, I don't think any part of your valve train is the problem if it is quiet when coasting or decelerating.

You say it "sounds like a diesel" when accelerating.

And it's definitely engine noise and not from further back in the power train?

Is it like a dull thudding knock, or a sharper rapping noise?

A dull knock could be a loose flywheel, or loose main bearings. (What is your oil pressure at idle?)

A sharp knock or rapping noise sounds like pre-ignition used to sound due to too much spark advance. (But I'm not sure if that's even possible with a compression ratio around 6.5 to 1 and 87 octane gas.)
Still...
Is your vacuum advance working?
If it isn't, and you've dialed a lot of advance in to compensate without knowing it, the advance won't be able to drop back as needed under load to prevent "pinging".

Just a few thoughts.

Hope you find the problem and it's an inexpensive and easy fix! 🙂

When he said it sounds like a diesel i pictured a whine or singing noise.

You could be right.
Maybe he did mean it sounded like a turbocharger.

But it still wouldn't go quiet when coasting right?

I went to look at a 1940 Chev once as a possible purchase.
I turned it down because of a loud and kind of gritty whine from the timing cover when he started the engine. (That and too much Bondo)

I appreciate all the hypotheses on my engine noise. The motor is performing well. Starts with a touch of the button. Temp is perfect.
The sound is not a whine but rather a sound similar to the injector noise on my 95 Massey Ferguson. Only the ticks a lot closer together like would happen with a gear. But not like a missing tooth. Like every tooth is making a tick. I use non ethanol 93 octane gas and set spark at 8°
ahead.. I will see if I can get my neighbor to accelerate the motor while I put a pvc pipe to the timing cover.

Some past post regarding engine noise discussed bent push rod hitting the side cover. Might be worth checking.

With a bent push rod there would be a dead miss. Right? Theres no miss. And the sound is a staccatto . Very close together. We will put the listening pipe to it.

The fact that it show up as the engine speeds up would indicTE A LOOSE MAIN OR ROD BEARING, PISTON, OR ???
a SLIGHTLY BENT PUSH ROD WOULD DO IT UDER ALL CONDITIONS.

iS THE NOISE THE SAME WIH HOT OR COLD ENGINE

cAN IT BE HEAR DHEN DRTVING/

dOES IT CHANGE WHEN A CYINDER IS SHORTED OUT

iS THE FAN BELT LOOSE?

DOES IT GO AWAY WHEN THE FAN BELT S RMOVED?

It is heard hot or cold. The frequency is too high for a single bearing. Its not a belt squeal or the water pump. It seems to be comimg from the timing cover. So I'll pull it off and see what is the matter.
Thanks for all the responses..

Try oiling the cover seal Sounds if the seal is running dry,
Squirt oil or WD40 behind the balancer.

hope he sees this before doing major inspection.

bump

Thanks for all the brainstorming guys. Thats what this chat is ll about. Nany tvanks.