Chasing the knock.

Garagekulture13 said:
Well I got this far today. I hope this is evidence this is my knock. Also that's my son at the end. He had to get in there and help.

https://youtu.be/lDI6grnm-Z0
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If your just replacing the timing gear. That could have been done without removing the front of car. You can do it even with the hood left on.

Remove generator, fan belt, timing gear cover, timing gear. Than reverse process, and your done. Couple of hours work.
 
I think that is a neat video!

You can sure hear and see that cam gear "slap" when the valve spring pressure on it changes.

I did about the same amount of disassembly when I got mine home, only it was to change the leaking water pump and four blade fan.

No better way to learn how to disassemble and reassemble a Model A and a good opportunity to back flush the radiator.

I've had it apart three or four times since then.
 
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Don't know if changing the gear will cure your knock,but it will run better that's for sure.Valve timing that far out is bad..bet it wouldn't pull your hat off
 
WHN said:
If your just replacing the timing gear. That could have been done without removing the front of car. You can do it even with the hood left on.

Remove generator, fan belt, timing gear cover, timing gear. Than reverse process, and your done. Couple of hours work.
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After further inspection I could see the crank gear had some pitting in one area. That pitted area coincided with the worn area on the timing gear. I assume someone replaced the timing gear at some point and did not replace the crank gear explaining the premature failure of the timing gear. So I plan to replace both.

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The knock sounds familiar and my guess is the timing gear is worn. You can do a simple test to identify if it is the timing gear. Remove the timing pin on the bottom front of engine. Start the engine and slowly insert the timing pin into the timing hole with the rounded end of pin. Push the pin against the cam gear and if the knocking noise changes, gets softer this means it needs to be replaced. Usually the wear occurs on the ID of the gear or the nut can come loose creating excessive backlash.
 
It just means that your fiber timing gear is so worn that as the engine is running and driving the timing will be constantly advancing or retarding because of the sloppiness of the meshing of the gears. its operation will be very inconsistent. When you put your new cam gear in you will notice a very nice even running engine.
 
It means you valve timing does not correspond with your piston position.basically your fixing a performance issue hoping it fixes a knock...
 
Crankshaft gear I got from Snyder's differs from the gear I removed. When I line up the keyways you can see the teeth are about half a tooth off. Also the timing marks are 1 tooth different. Would this not throw the timing off?
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Also my timing cover camshaft plunger is shower some wear. The X is still visible and I would assume it's still good. Your thoughts? Also spring feels stiff. I believe it to be good.
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That is probably a gear from the 70ts. They were off a bout a 1/2 tooth. Good thing you went all the way and found it. It will have more power now.
 
I also hope you are going with a good cam gear. bronze is the best, alum gear next, then laminated next, macerated is junk in my book.
 
Ok. New gears and still have crazy backlash. So what is this telling me? I see hundreds of post about backlash but have yet to see one say what it means if you have a lot.
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Your latest picture doesn't show gear backlash. It appears to me to show crankshaft endplay. 2 different animals.

Gear back lash is checked by inserting feeler gauges between the crank gear and cam gear teeth. As mentioned before it should be in the .004-.007" range. If a .010" strip will slide thru, you still have too much lash.
 
Patrick L. said:
Your latest picture doesn't show gear backlash. It appears to me to show crankshaft endplay. 2 different animals.

Gear back lash is checked by inserting feeler gauges between the crank gear and cam gear teeth. As mentioned before it should be in the .004-.007" range. If a .010" strip will slide thru, you still have too much lash.
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Thanks for clearing that up. I understand now. The gear in the picture is the camshaft.

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