Cam Gear

[Jerry in Shasta]

I installed an aluminum cam gear in my sdn.
It makes a knocking noise like a rod bearing.
Put in a bronze and it did the same thing.

Put in a fiber gear,, no noise!

The cam is not walking back and forth, and
the crank gear is new.

Could it be that the crank gear has narrow tooth
causing it to slap as the gears mesh??

I need the metallic gear because I have a heavy
valve spring load.

Thanks
JB

[BRENT in 10-uh-C]

O/S Aluminum Gear? What kind of backlash with the aluminum & bronze gear? Naturally, the metallic gears will be noisier but not always a problem. There may be an issue with the crank gear that the fiber gear is masking.



.

[Dan McEachern]

Jerry- Did you check the backlash as Brent asked?
You should check it at 90 degree intervals. How did you tighten the cam gear nut? Look at the wear pattern on the cam gear teeth- it should be uniform all the way across the tooth and be the same on both sides of the tooth if the gears are made correctly.

If you need help, e-mail me- dmcgears AT yahoo.com.

Dan

[BILL WILLIAMSON]

Originally Posted by Jerry in Shasta

I installed an aluminum cam gear in my sdn.
It makes a knocking noise like a rod bearing.
Put in a bronze and it did the same thing.

Put in a fiber gear,, no noise!

The cam is not walking back and forth, and
the crank gear is new.

Could it be that the crank gear has narrow tooth
causing it to slap as the gears mesh??

I need the metallic gear because I have a heavy
valve spring load.

Thanks
JB

Bronze timing gear was a little noisy in my '30, but after 5,000 miles, the noise gradually went away. I do have the external 1/8 inch tubing oiler from the oil pump fitting that goes to a drilled hole in the side timing cover upper bolt for positive gear lubrication to gear teeth. My experience with early Volvo, factory supplied aluminum cam gear for longer life than the fibre gear, very noisy, they tried iron cam gear and the noise was unbearable, even though the gears are lubricated by an oil spray orfice. Conclusion: any metal gears are noisy, but dependable!
"THE ASSISTANT GURU OF STUFF"

[pat in Santa Cruz]

did you install a matched set? is the crank gear used? Your best bet is to get a matched set from Dan.

[ford1]

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are you sure the crank pully isnt moving back and forth? grab ahold of it and see if it moves when rocking it back and forth on the crank, crank bolt may be bottoming out before pully gets tight

[Glenn C.]

Don't bother to run any new cam gear against a used crank gear. They new crank gear will be worn. Difficult to check by sight in the engine

[Mikeinnj]

Did you grease the cam plunger and spring in the timing cover when you installed it ? It will make a racket if you don't.

[Dave in MN]

Originally Posted by Jerry in Shasta

I installed an aluminum cam gear in my sdn.

Originally Posted by Jerry in Shasta

It makes a knocking noise like a rod bearing.
Put in a bronze and it did the same thing.

Put in a fiber gear,, no noise!

The cam is not walking back and forth, and
the crank gear is new.

Could it be that the crank gear has narrow tooth
causing it to slap as the gears mesh??

I need the metallic gear because I have a heavy
valve spring load.

Thanks
JB

It is possible that you have excessive clearance between the center journal of the cam and the block. Is your engine a recent re-build? The sound you describe "rod knock" is pretty close to the sound of an excessive clearance noise. Someone mentioned earlier that changing a timing gear may change the dynamics...he is right, it most often will and that may be just enough to hide the problem. You also mentioned you have a heavy valve spring load. Was valve work a recent change? #2 & #3 cylinder cam lobes engaging the lifters may be causing the cam to deflect. One way to tell if you have excessive center journal clearance is to install a .010" oversize oil pump drive gear and test run it. The oversize gear will often stop the cam from dancing around in the block. Installing the oversize gear and leaving it will not fix the problem. The gear will quickly wear in and the noise will be back. If this is your problem, the best solution is to find a cam with little wear or order a nice shiny new one from Bill Stipe at: Specialty Motor Cams. http://www.specialtymotorcams.com/
Good luck on your search for the problem! Simple little cars should have simple to repair little problems...well we all know that's wrong!
Good Day!
Dave in MN