Is anyone using the camshaft thurst bushing kit? The bushing designed to prevent the #1 cam lobe from hitting the #1 cam bearing.
Where does the bushing go and does it do as intended? Do it prevent the hitting of the two parts?

If it's the bushing I'm thinking about, it gets sandwiched between the timing gear cover and the camshaft gear lock nut. Some fitting is required since the bushing thickness can vary from engine to engine to some extent. A friend of mine gave me one he had made about 20 years ago. It's in a '26 engine that I have.

A buddy of mine that I fit a new crankshaft for bought one as the cam in his car had alot of end play and he either needed a new cam or stop it from moving. The kit contains some hardened washers (thin) and as Warren pointed out it sandwiches between the cam gear and timing cover. On the inside of the cover there is a slight rise near the hole for the cam that I cleaned off with and air sander. It took me maybe 10 minutes to put it in (during engine assembly) and the measured end play is now .003 and it makes no noise.

I think it is well worth while especially in cases like his where the cam is fine other than the end play issue. Hope this helps.

The biggest variable in fitting the cam thrust washer assembly is the thickness of the cam gear hub. This is a large variable depending on whether it is an original steel gear or a fibre, aluminum , bronze or nylon. Their all different. There is no one size fitts all, you have to adjust the thickness of the brass washer to fit your engine. This is something I started doing years age because I knew why the front cam bearings were knocking. We include this kit with all 09-25 regroung cams we sell. No one else selling reground cams provides the kit or even seems to know that there is a problem with reground early cams.

You guys have me thinking now. My brand new, freshly rebuilt motor is making a knocking sound!

It has a new "280 lift"(?)camshaft. Is that making the sound I hear? How can I check endplay? Do I have to disassemble the front of the engine to do it?

Thanks.

Steve

Steve, The problem only occurs when you regring an early cam (09-24) The early front cam bearing is longer than the later design and has a slot in the back thrust surface for clearance of the front lifter. The heel and front surface of the front cam lobe both serve as a thrust surface against the backside of the front cam bearing. When you regrind a cam, much if not all, of the heel is ground away so that the base circle of the front lobe is about the same diameter dimension as the front cam bearing. This leaves only the front side of the toe as a thrust surfece. When the toe lines up with the slot in the backside of the front bearing there is nothing to keep the cam from moving forward into the bearing slot. If this happins the cam will create a knock as the front lobe is knocked backwards trying to exit the slot. This has long been the source of mysterious knocks in the front of the engine with no apparent source. The problem has been around for a long time and has been totally ignored by most cam grinders. It is not a problem with the later 25-27 cams as the front bearig is shorter and the bearing has no notch.

Glen,

Thank you for the explanation. As you can imagine, I'm not real thrilled with the noise.

Is this fixable? Does this "shim kit" work? Am I doing damage to the engine running it like this?

At this point, I don't know what to do with it. I don't want to cause harm to it by using it all summer. And the thought of removing it and taking it back to the builder is making my blood pressure rise.

Whats your advice on this dillema?

Thanks.

Steve

Steve you did not say what year your motor is. If it has a generator you might want to remove it and see if that clears up your knock. I rebuilt an engine twice looking to stop a knock and it was the gen all the time. Eliminate the simple things first. That being said a new rebuilt engine should not knock. Things that cause knocks: timing too high : field coils hitting magnets: magnets hitting the inside oil tube : and incorectly adjusted bearings: broken crank: pistons hitting head: just to name few.
Good luck
Calvin

Steve,I have no personal experience with the a high kift cam.But,not long ago someone in my group of T friends got a knock after putting one in.I believe he found a lifter or lifters were hitting the bottom of the valve chamber,or something, due to the higher lift of the cam.I might be wrong on this as I did not discuss this directly with him.A little grinding solved the problem.Perhaps Glen will chime in on this.

Jim is correct, If you are using a new high lift cam there is a possibility that one or more lifters are hitting the bottom of the block casting as they are lifted. It all depends on the brand of lifter you are using and the particular block, There are many variables and deserve checking. Removing the generator, if you have one, is an easy test as Calvin suggests. I have never had this problem but is is a possibility. If neither of these possibilities are at fault and you have eliminated the bearings and piston hitting the head as faults then you probably have a cam knock problem. I would eliminate all of the above first then pull the cam and look at the backside of the front cam bearing. You should see evidence of the front lobe hitting the side of the rear notch. The thrust washer kit will solve the problem and cause no harm to your engine. One steel washer is pushed onto the cam gear nut with the chamferred hole facing the nut to clear the radius of the nut. The brass washer is installed next with the second steel washer acting as a thrust surface against the inside of the front timing cover. The brass washer thickness is adjusted to give you .002-0.005 clearance. The parts are lubricated by the splash system but I would prelube them with some wheel bearing grease on installation. Hope this helps.

Hi Guy's,

The engine is a '23 and it has a generator. How was the generator making the knocking noise? What was wrong with it?

The engine was rebuilt by a local rebuilder who has hundreds of T engines under his belt. Well known and trusted. I can't believe that this problem should have been known and taken care of. Very, very disapointing.

Will I damage the engine if I continue to use it with a camshaft-caused knocking noise? I'm guessing here, but there must be thousands of T's out there with this problem? And their still going, correct?

Or should it be taken apart right now and fixed?

Will it stop making noise eventually, or will it just keep grinding itself down to a point where it's beyond repair?

Just trying to get a mental handle on this thing.

Thanks guy's.

Steve

First, find out what is causing the noise, then fix it. Don't continue to drive the car. Did you remove the generator as suggested? If not, do it. Eliminate the easy things first. With regard to the cam. If it is a new cam it should not have this problem. However, the problem could also be a cam bearing with too much clearance or a front cam bearing that is a very loose fit in the bore of the block. If the front lobe of the cam is hitting the sides of the cam bearing rear notch then you could be damaging both the front lobe of the cam and the cam bearing.

Glen I recieved this kit friday. I see your the designer. I have a noise in the engine I just can't figure out. When I rebuild the engine the cam seemed ok and it bearings seemed ok so I put then back in. My knock comes from the cam side of engine and can be heard from the front of engine back to the tranny. I was wondereding if the cam could be walking back and forth causing the knock. I thought I would try your repair before I took the engine down again. Im sure it is not piston, main, or rod noise. I do not always get this noise when I start the car but I do after revving the engine.

Ty,

If your car has the straight-cut timing gears like mine did, I think it will be more likely to make lots of valve train noise even if backlash isn't excessive.

Glen's thrust bearing kit should help, I think.

Good luck with it!

Seth

thanks ol Seth. Glad to see ya still around.

T, You still haven't answered our question. Is your cam a reground early cam? Seth is right about the straight cut gears but they should not cause much noise unless you have way too much clearance. The cam will not walk back and forth unless you have to much end play in the front cam bushing. However, this will not cause a knock unless you have an early reground cam with no thrust washer assembly installed.

Glen, I can not answer your question. At the time I put the engine together, I had never seen the inside of a T engine. I have on idea at this point if the cam had ever been ground or not.
I put the kit in today and will start it tomorrow. I found today I could move the cam in and out I'm guessing 1/16 - 1/8" +/-. Gear lash was good.
Will fire it up tomorrow and post my findinds.