Timing Gear/Crank Gear issue

Okay Gents, some progress has been made. I just finished pulling the timing cover off, and there were some interesting finds. First, both the cam gear and the crank gear appear to be missing teeth (you can see remnants on the baffles of the oil pan). second, it appears that the cam thrust plunger has disappeared. Lastly, upon inspection, it would appear that the thrust plunger spring is among the culprits that caused the issue in the first place. It does not have even close to 35 # of pressure.

So, I feel that the plunger let go thus causing the timing gear to wobble; therefore grinding the teeth of both the timing gear and the crank gear down to nothing. Sorry about the lack of photos, but its a little dark in the barn.

thoughts?
 
Hi 30,

1. Per your reply no. 3" "Is it possible that the crank gear could have lost teeth?"; and,

2. Per your reply no. 21: "thoughts?"; in my humble opinion,

3. Most will agree, with Model A's, after we all thought we saw it all, there is always a possible unseen Model A mechanical surprise around the corner.

4. Per the phone number in reply no 20, if you call Mr. McEachern, you can receive expert timing gear advice and meet a very professional gentleman willing to assist.
 
That happened to me back in the 70s. I put on a new fiber timing gear and it lasted about 50 miles. I then noticed that the crank gear was pitted and rough. Rather than changing the crank gear, I put on an aluminum timing gear. That solved the problem until I disassembled the car for a complete restoration. I now use only metal timing gears.
 
I lost a Westinghouse "Micarta" cam gear in my unrestored coupe a few years ago.

The fibre worked loose from the steel hub.

I decided to go with an aluminum gear from one of the usual suppliers, aware of the cautions about gear noise, but figured that going into an 80,000 mile engine, there were enough other noises that some gear noise would not be noticed.

During the repair, I also checked-out the cam plunger and spring.

I found the plunger galled and pitted along its length, and the spring was broken in several places, essentially allowing it to collapse. The plunger was flush with the bore in the cover, and essentially was doing nothing.

I also noticed wear marks on the front rim of the cam gear, with matching rubs on the inside of the timing cover.

Apparently, the plunger spring had failed some time ago, and was allowing the cam to "walk" back and forth, with the cam gear slapping against the timing cover.

At idle, this sounded very much like a rod knock.

With the new aluminum gear, new plunger and spring, the engine ran well, and the "rod knock" had disappeared.

Big lesson for me: ALWAYS inspect cam plunger and spring !

Good luck with your repair !

Frank
 
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