camshaft - block noise spring and plunger?

M

machineman64

Member
i have a loud knocking coming from the front of the camshaft this has been verified by inserting a flat pin in the timing hole and pushing on it, when i push on the pin the noise goes away. i have replaced the plunger and spring also increased the spring pressure with a 5/16 shim. the noise presists and i am tired of r&r the timing gear cover, have checked for loose cam gear nut, it is tite.

i understand a fellow by the name of Stan Vermeil supplys a timing gear cover with a adjustible thrust bearing to replace the plunger and spring. my question is does anyone know his contact info. or does anyone have a picture of this set up?

any help appreciated
thanks John
 
You may want to try a stronger spring. I had the same problem after installing the Stipe oil pump and a pressurized oil system. I purchased a 200 lb/in spring from Hardware Products Company, http://www.hardwareproducts.com , PN 10088, price=$38.02 for 10 springs (minimum order). It worked great, no more noises, problem repaired.
 
I had the same problem a few of years ago. I did all the things you did to the cam plunger and spring and still had the noise. I took the car to a very experienced mechanic. He listened to the noise at various engine speeds. He said it was not the cam but a piston slap on number one cylinder. He said this is not unusual for a Model A, and it will run a long time that way and likely would not get worse, but it was my choice to repair it or not. I decided not to repair it unless it got worse and thats nearly three years ago. I did go to 15W-40 oil and its much quieter now, so won't bother with it until future overhaul. Your choice.
 
If the cam is riding the gear and snapping,something else is wrong. Check the distributor or the oil pump for bad bushings. If you put a solid plunger in you will break something, most likely the cam or gear.
 
did you put a new oil pump drive in lately
i have seen the new repo parts be out of tolerance and make the cam ride forward into the front cover
tk
 
Hi All,

I am sure it is NOT piston slap, as i said it goes away when i insert a flat timing pin in the timing hole and push on it. I removed the pan and checked bearing clearance, cylinder walls all look like new from under side, no excessive front to rear movement of crank, no broken rings, looked in top of cylinder with bore scope cylinder walls look good. aluminum timing gear. still looking for Stan Vermeil contact info. or info about his conversion.
 
Stan Vermeil is in Santa Rosa,Ca. You can get his contact info from the phone company.
Using one of Stan's front covers will cure the problem.

The rest of you guys need to learn to ABSORB and decipher the information you read.

1- He said the cam nut was tight.

2- He said pushing on the end of the cam made the noise go away. That won't cure piston slap.
 
Stan moved to Grass Valley, CA. I dont have his contact info up there. His setup uses a Chevy Camshaft Thrust Button available at Summit Racing. You have to modify the gear cover. However, I would be surprised if anything much less than a fairly hot engine with markedly increased spring pressures would produce "cam walk" or if you have it that pushing the gear with a pin would be sufficient to hold it in place. I agree with James that something else is wrong. I have read here that some of the cam gears with a metal or some other type of center get loose in the center and make a knock sound and replacing the gear cures it.
 
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Have you checked the gear lash ? The clearance should be in the .004-.006" range. If you can fit a .010" strip in the teeth, it'll rattle.
If a new distributor drive gear has been installed, sometimes it takes a while for those gears to get used to other and they will rattle and argue with each other for awhile.
 
Machineman64,
This problem is frustrating isn't it! Believe me I know. Please let us know if you have completed any recent modifications to the engine just prior to the noise developing. I call your problem "cam walk"...the noise or tap is the thrust surfaces between the cam and the block slamming back together when the force pushing them apart subsides. This condition can also be caused by a worn center cam journal or worn block bore in the same area. Pay attention to James Rogers, Kelly's Restoration and Patrick L. as they make valid points as to possibilities. I would echo their comments/suggestions. I have been in your shoes...many times with the same problem when I work on others cars...if the cam plunger spring has been replaced and even shimmed and the problem still persists, the cause is probably one of the items these gents suggest. You can stop the noise with what you are looking to do but the best fix may be to find the real cause and correct it instead. Hope this helps. PM your phone number to me...I'll call and elaborate a few of my experiences and solutions.
Good Day!
 
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I had a customer to bring a motor back once with a very loud knock he claimed was a rod or main. I told him to bring the complete motor back with the distributor and water pump still on it and I would make it good. I removed his distributor and could hardly turn it. Rebuilt the distributor and it purred like a kitten. I make good money for petty repairs like these.

Dave is absolutely correct.
 
Pete said:
Stan Vermeil is in Santa Rosa,Ca. You can get his contact info from the phone company.
Using one of Stan's front covers will cure the problem.

The rest of you guys need to learn to ABSORB and decipher the information you read.

1- He said the cam nut was tight.

2- He said pushing on the end of the cam made the noise go away. That won't cure piston slap.
Click to expand...

Yep,...your correct! When I read the first sentence, my first thought was
the cam driven gear, for the Dist / OP...being out of round OR too large
of an OD.
 
I like the strong spring idea, and the faulty inner portion of the fibre gear. Great thread. A lot of excellent advice for us all. Bob
 
I'll try give a update and a little more info. on the car. First i have owned the car about a year, i have not been able to find out any history, the car has a counter balanced crank stamped 5-85. Everything top and bottom of engine looks and checks out very good, engine runs very good, uses no oil, pulls good but has this LOUD noise from the cam.

Jim you are right there is a drag on the dist. drive I removed the dist. and it has a one piece shaft but the dist. turns smooth as silk when out of the engine, no play however i ordered a new two piece shaft from Bert's (there the best) also removed the op/ dist drive again everything looked good and turned free. I did order a new shaft with gear, Also oil pump turns free. Why the dist. turns hard in the engine i have not determined yet.

Dave i have not replaced any parts or done any work on the engine, it ran very good last summer, started this early this spring. I have done lots of work on the breaks, rear end, throw out brg, rebuilt the gen. and starter. p/m you my phone no. you can call most any time i'm here most of the time.

John
 
I believe you have found the problem. These engines have run for 85 years without any aftermarket junk to cover up a problem.
 
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