Camshaft Movement

[Mercmarc]

Hello All,

MercMarc here with a question.

Facts as I know them:

1953 239, dual carb, Isky 88 cam, Adjustable lifters, Aluminum cam gear, EAB heads, stock bypass oil filter style.

1950 239, dual carb, Isky 88 cam, Adjustable lifter, Fiber cam gear, EAB heads, full pressure oil filter upgrade.

Both engines experienced failure with in 10 hours of run time due to the cam shaft walking forward into the cast iron timing gear cover, eating the aluminum cam gear sending metal particle throughout the engine. The second engine has a fiber gear and was caught earlier so little cam gear damage but the cast iron cam gear cover was ground away by the 4 cam bolts. Both engines were professionally built by an west coast shop. Turn key engines, both engines started and ran great, a noise was heard radiating from the distributor area sounding very similar to a dist rotor hitting the inside of the dist cap. After removing the dist cap there was no evidence of the parts hitting each other.

Note:
The first engine was replaced in totality without question or disassembly by the shop when I told them I was having trouble with the engine.

Question:

What would cause a camshaft to walk forward on these engines?

Thank you

[tubman]

Using a cam meant for a pre-8BA engine? (They thrust the opposite way.)

[GOSFAST]

Hi Marc, just out of curiosity whose lifters did you use, were they the original Johnson's OR just Johnson "styles".

If possible look VERY closely at the lifter adjusting nuts where they contact the valve tips, see if they are perfectly "flat" or if they are "radiused" some??

Thanks, Gary in N.Y.

P.S. I'll also come back later with a way to help keep the cam "where it belongs" so to speak! The very simple method will work providing you have no other underlying issues?

[jetmek]

Dont get it. The dist drive gear would contact the cover before the bolts and in any application the bolts aren’t proud of the front of the cam gear. What ever you have going on it sounds like the wrong timing gear set was used

[flatheadmurre]

Since they both are 8BA generation putting in an early camgear doesn´t matter...will just put trust back againt block.
8BA should have the cam rest against the front cover...but if you start to increase the load on the cam with stiffer springs so does the forward force.
So did someone by chance put an early ignition on it ??
With a proper ignition cover cam would have to eat a hole in the center before the gear hits the cover...

[flatjack9]

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Originally Posted by tubman

Using a cam meant for a pre-8BA engine? (They thrust the opposite way.)

Thrust is toward the block, rather than the cover.

[Mercmarc]

Thank you all for jumping in on this thread, all very helpful. I am trying to post a picture or two so please stand by

[Mercmarc]

Here is a picture showing the cam gear rubbing on the cover as well

[Mercmarc]

Thank you Tubman, I will try to confirm the cam application

Hello GOFAST, I only have pictures from the first engine and that one had as it turns out non adjustable lifters. I requested adjustable lifters for the second engine but I do not have a picture to review.

Hello jetmek, Hopefully the pictures better explain what I am looking at.

Hello flatheadmurre, I was told the valve springs are of the Lincoln Zepher type and rating. This may be nothing more than the wrong cover on two engines then. If I am understanding correctly, on 8BA motors, the dist drive gear on the cam actually rubs the front cover as it appears to do? I would hope cam thrust would be towards the block.

Again many thanks to everyones input, time and help

Respectfully

Marc

[jetmek]

Looks like a bolted on dist drive adapter for an early cam??? Its making the bolt heads way too far fwd and contacting the cover

[Mercmarc]

Hello etmek,

Would this also explain the cam gear rubbing the cover as well?

[flatheadmurre]

That is a result of bolting togetter the wrong parts...
A bit of grinding and checking axial play of the camshaft...or getting the correct cam...or going for an aluminum cover with bottom support for the distributor...many solutions...
All comes down to the same bottom line...the guy assembling it didn´t check his work...that cam must have made noise from start...or the adapter is to short with excessive endplay.

[jetmek]

Normal for the dist drive gear to contact the machined boss in front cover

[Mercmarc]

Hello jetmek, thank you for confirming the drive gear contact is normal.

Hello flatheadmurre, I agree on all accounts of your latest reply. And yes the engine did make noise from the beginning albeit subtle most of the time. Very similar to a rotor and cap click, until literally, one day the noise became quite profound and I stopped running it. I challenged the builder on the noise and was told he never heard of such a thing.

[GOSFAST]

Originally Posted by jetmek

Normal for the dist drive gear to contact the machined boss in front cover

This is easily controlled, we just delivered 2 builds with the "fix", worked like charm!

Thanks, Gary in N.Y.

P.S. Here's a shot of an easy way to avoid the cam or gear from making contact with the cover! That is a Comp Cams (SBC) nylon "button" with the end play checked and adjusted as needed!

[Ronnieroadster]

Originally Posted by tubman

Using a cam meant for a pre-8BA engine? (They thrust the opposite way.)

8BA cam gears pitch forward and early cam gears thrust towards the block. However once the oil pump drive is installed and the torque required to turn the pump comes into play even the early cam gear will thrust forward.

[Mercmarc]

Hello Gary in NY, Many thanks for the picture and follow up.

Thank you Ronnieroadster, for the direction of cam thrust.

To everyone who has jumped in on this thread THANK YOU. I am waiting to hear from the builder to discuss options if any and to share with him what has been learned so he does not repeat the same mistakes again to anyone else.

Respectfully and Sincerely

Marc

[Mercmarc]

FORDBARN FORUM

WHAT A GREAT TOOL AND GIFT OF FRIENDS

Marc

[flatheadmurre]

Originally Posted by GOSFAST

This is easily controlled, we just delivered 2 builds with the "fix", worked like charm!

Thanks, Gary in N.Y.

P.S. Here's a shot of an easy way to avoid the cam or gear from making contact with the cover! That is a Comp Cams (SBC) nylon "button" with the end play checked and adjusted as needed!

Looks like that solution will plug the oilhole coming out of the cam lubricating the drivegears...or am i missing some solution to that ?

[Fordestes]

IF the crank and cam gears are new aftermarket, check to see if the gear has been marked on the wrong side, the crank gear timing dot should be on the side with center flush with the gear face, there is about 1/8 inch offset on the rear of the crank timing gear, it may be mis- manufactured and marked on the wrong side while running the gears may be trying to correct the centering by moving the cam gear forward. I would check the cam gear also , I find some of the name brand parts have been shipped before the mistakes were realized thus creating a hair pulling problem . is it possible the add on dist. drive is incorrectly made ? Having two engines in succession with the exact same problem sounds like some mis-manufactured parts . Keep us in the loop.

[Mercmarc]

Hello Fordestes,

I checked for gear markings and they are on the same side facing forward. Yes the crank gear does have about an 1/8 inch offset to the rear.

I will definitely keep the post in the loop.

Rescpecfully

Marc

[flatjack9]

What oil pump are you using and are you running a stock fuel pump?

[Mercmarc]

Hello Flatjack9,

I have 65 psi OP at cold idle (600RPM) and 50 psi OP at 180 degrees idle. I believe I see upwards of 75 at 2000 RPM at 180 degrees. Full flow and pressure fire wall mounted oil filter.

I don't see the photos I attached earlier so I will try this again. Please forgive me if they are duplicates.

[Mercmarc]

Hello flatjack 9

Yes a stock fuel pump

[Mercmarc]

Hello flapjack 9

Just a view of the fuel pump

[Mercmarc]

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Quote:
Originally Posted by GOSFAST View Post
This is easily controlled, we just delivered 2 builds with the "fix", worked like charm!

Thanks, Gary in N.Y.

P.S. Here's a shot of an easy way to avoid the cam or gear from making contact with the cover! That is a Comp Cams (SBC) nylon "button" with the end play checked and adjusted as needed!
Looks like that solution will plug the oilhole coming out of the cam lubricating the drivegears...or am i missing some solution to that ?

Hello Flatheadmurre, I looked closely at and around the distributor drive gear and do not see an oil hole out the end of the cam or anywhere around the area. Oil diagrams indicate the cam and crank gear receive their oil from the front cam bearing. I noticed the only lube on the end of the distributor when I removed it for this inspection was the grease that I put on the teeth. Makes me even more concerned about correct mix and match of parts.

Thank you

Marc

[Ol' Ron]

There are 2 typed of early cam Blanks. One has a flush mount cam drive, the other with an extendes cam drive. IF an adapter was used on the latter cam it would bove the cam out aprox 1/6 inch, unless the back side was relieved. I ran into this problem many years ago. However, the engine wouldn't turn over when I bolted on the cover. I could see the gear was forward and discovered the mistake. Making mistakes, makes you very smart.????

[Mercmarc]

Good morning Ol'Ron,
Thank you for the information, I am removing the drive gear today to see what I find behind it. I am trying to be respectful of the builder (still waiting for a reply) and don't wasn't to investigate anymore than what is needed to very a problem which we have done. I am most curious regarding what the actual problem is and everyone here on Ford Barn has been most helpful with that. I will keep the updates coming until a conclusion is reached.

Sincerely

Marc

[GOSFAST]

Originally Posted by flatheadmurre

Looks like that solution will plug the oilhole coming out of the cam lubricating the drivegears...or am i missing some solution to that ?

Let me clear up a bit why we place that button in there. It isn't meant to ride on the front of the cam, it's meant to keep any metal from contaminating the build in the event of what happened to Marc here. It would be hard to have the cam gear or cam run into the cover while that nylon button is in there. The button will stop the cam/gear from moving into the cover!

Thanks, Gary in N.Y.

P.S. Not sure still what Marc's problem is here but I was hoping to find out if his adjustable lifters had "flat-faced" adjusting screws where the valve tip resides?? The screw heads are designed to have a very slight radius, just like the face of the lifters where they ride on the lobes!

[Mercmarc]

Hello GOFAST,

I Greatlyappreciate the clarification of the button application. Maes perfect sense to me. It appears that the builder used a bit of mix and match parts without confirming usable application, either by 1st hand experience or some other history. Yes, two engines with the same problem, I need to know what and why and how not to if I go to build one my self instead of a third engine.

As for the lifters, I do not have any pictures of the second engines valve train to very flat or crowned adjusting stems. I have pictures of the first engine with had crowned or domed non adjustable lifters, but that engine had the same problem looking back at the history of aluminum material in the oil from an unknown source. Well it had the same distributor clicking noise and an aluminum timing gear. I did not take that engine apart to confirm a source of the noise or metal when the builder said bring it back and I will build you another new one, no questions asked. I believe what we have discovered is the same set of mix and match conditions leading to the same result, now that we know what the source of the noise is. Unfortunately there is a significant amount of ground up metal that has been run through the engine that may or may not have been filtered out by the oil filter. I won't know until I hear from the builder as to what direction he wants me to go.

Respectfully

Marc

[Mercmarc]

I should proof read better before hitting replay


Reply. :-)

[glennpm]

Oh Boy!


Do I know about the SBC cam button. I built a small block many years ago when I worked at a Shell station. The noise drove me nuts (without the button). I didn't know whether it was a bearing or what. Wood stick stethoscope didn't find it. My boss, the other mechanic in our station and the other knowledgeable mechanics in town didn't have a clue.


I figured I'd have to pull the motor. My boss said, run it till it gets worse. I was changing the timing cover to a two-piece design to fix a small oil leak. pushed on the end of the cam and alas there was the noise!!


Glenn

Originally Posted by GOSFAST

This is easily controlled, we just delivered 2 builds with the "fix", worked like charm!

Thanks, Gary in N.Y.

P.S. Here's a shot of an easy way to avoid the cam or gear from making contact with the cover! That is a Comp Cams (SBC) nylon "button" with the end play checked and adjusted as needed!

[Mercmarc]

Hello glennpm

Many thanks for sharing, was there any chain rubbing contact with the original sheet metal timing case cover? Or was there some other guteral noise since the cam was moving?

Respectfully

Marc

[glennpm]

Okay this was a long time ago but I can't forget the noise it made. It was a hollow knock that you could hear intermittently. The kind of noise when you suck your tongue of the roof of your mouth ;-) You would hear it during RPM reduction. I guess a little chain slack that let the cam pulley walk to and knock on the block and make a cluck/knock noise.

I don't remember see any chain scraping or tapping evidence in the front inside of the timing cover case. Definitely no scraping noise from the chain.

Glenn

[flatjack9]

Chain?

[JSeery]

Originally Posted by flatjack9

Chain?

They're talking SBC and cam walk.

[Mercmarc]

Thank you glennpm, amazing how some sounds just stay in the memory banks.

:-)

[Mercmarc]

Hello gosfast,

Regarding the lifters in the second engine, below is the most accurate information I could find.

I looked up the Reds Heads Lincoln Zepher style adjustable lifters that I understood were installed in the second engine. Looking closely at the pictures of said lifters, they appear to be ground flat across the adjusting nut area where the valve stem makes contact.

The first engine's non adjustable lifters are very clear domed or crowned.

Thanks again for everyones input and help. Still waiting to hear from the builder.

Respectfully

Marc

[Bored&Stroked]

Another thing to consider is if they are using an early cam (with an adapter for the distributor drive bolted onto it - which is what I see), then they probably do NOT have the oiling provision that Ford added to pass oil from the front cam journal to the front of the snout of the cam. This did not exist from 32 - 48 and it is very important when running the later timing gears and the side-mount distributor timing cover.

Unless they drilled the cam journal and center drilled the cam shout (highly unlikely), then this is most likely your problem. Without pressurized oil to this front thrust surface, you have direct metal on metal contact - so you'll soon have the very issue you speak of. This is also the reason that Ford switched the timing gear teeth angle - they wanted the cam to touch the front cover and ride against it. This is a mistake on the builder's part . . . plain and simple.

Why - Thrust Direction Change: 1) It helps keep the distributor timing more consistent (cam touching the front all the time) - as when you allow the cam to walk, the timing advance will move as you let on-off the throttle (only takes a little movement to cause over 5 degrees of timing fluctuation. I prefer to setup the backlash/thrust to be as tight as possible - like .003-.004 - to limit any timing movements.

Fix: Outside the potential issue of the bolts hitting the cover, if you want to continue to run the early cam, then it needs to be correctly drilled and the front adapter needs to have a hole all the way through it (if it does not). Also, the forward thrust dimension needs to be as close to .004 as possible (with the gasket in). Beware, sometimes the wrong gasket thicknesses are used. Depending on the thrust, sometimes I remove the gasket and use RTV. Also, I've had to "tune" the flange thickness on certain cams before. Many ways to skin the cat - but the thrust dimension is important.

Note: The aluminum cover is a bit more forgiving (as it relates to the amount of oil) - but it should not be an issue either way (with correct oiling).

Here is the oiling hole on a 49-53 cam:

49-53Oiling.jpg

[Bored&Stroked]

Originally Posted by Mercmarc

Hello Flatjack9,

I have 65 psi OP at cold idle (600RPM) and 50 psi OP at 180 degrees idle. I believe I see upwards of 75 at 2000 RPM at 180 degrees. Full flow and pressure fire wall mounted oil filter.

I don't see the photos I attached earlier so I will try this again. Please forgive me if they are duplicates.

Just because you have an external oil filter, does not mean that it is 100% filtering the oil. Even if it is a modern-full-flow type system, it is doubtful that the oil pump was specifically modified for full-flow (which means a special TOP on it and oil lines that exit the side of the pan).

Most builders do a partial flow setup - where the rear main of the engine is still getting unfiltered oil. The term "95%" filtration is a common term used for this . . . but that is creative math in my mind . . . we have 3 mains in a flathead, two of which will get filtered oil (so not counting the cam bearings), I consider these partial full-flow mods to be a 66% filtration . . . not 95%.

Why is this important, well if you have metal running through the engine, you probably ran some through at least the rear main bearing and the rear cam bearing . . . and that is not a good situation.

[Mercmarc]

Hello Bored&Stroked,

I believe you have hit the proverbial nail on the head perfectly. I do not see a hole in the end of the cam adapter where oil under pressure would limit metal to metal contact on the timing case cover and what you are describing makes perfect sense. Yes the mounting bolts did hit and grind away a section of the cast iron cover.
Your explanation of the related oil filtration system is also spot on. :-) And I concur, three main bearings and only two benefiting from a filter equals 66% filtration. This is why I was so upset over finding the amount of metal missing and knowing where it ended up, that the rest of the engine has little value or reliability without complete teardown, cleaning and evaluation.
Your explanation about the importance of and changes Ford made regarding to cam thrust is greatly appreciated and very helpful. My abilities to build an engine today have since passed and I will be leaning on professionals to do so as much as it pains me. I have done the majority of the other work on the car minus the overhauling of a rear end, the upholstery and paint. Frame off redo to create a daily driver for my wife and I.

I am contacting H&H on Monday to see what if anything they can do for this engine. If nothing is the result, then I will be making other tough decisions.

Thank you very much for detailing what I knew and saw but did not know why.

Sincerely and respectfully

Marc

[Bored&Stroked]

I'm not one to bash anybody, but when one is paying an engine builder to build you an engine - they should at least know "what works with what".

And if the customer wants a bad/wrong combination, you refuse to do it. And when you make a mistake (and we all do), you make it right . . . simple business 101.

If you have any questions, feel free to PM me.

[cadillac512]

I wonder why an early camshaft + adapter was used (twice!) rather than the correct 8BA style which is correct for this engine. That really puzzles me...


Terry

[Mercmarc]

Hello Terry, cadillac512
Great question and one I intend to ask the builder. Especially after the fist one failed. I am also curious if these are the only two engines he built this way.

Respectfully

Marc

[Mercmarc]

Hello To everyone who weighed in on this cam movement thread.

Wrap up:

The cause of the cam movement as mentioned by several, is a case of using the wrong parts for the application without the proper modifications. Early cam and adapter with no provision for oiling the front of the cam and distributor area. I have yet to determine why the builder chose to use the parts he did, but says he will stand behind his build.

I am very grateful to all who participated in this thread.

Respectfully

Marc

[tubman]

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Marc,

Thanks for getting back to us on this. It's always good to find out what really was going on.

[Mercmarc]

Hello All,

Camshaft movement update on 2/4/2022.

Firstly, please accept my apologies for such a long delay for an update. No excuses just life happens.

Summary of discovery,

I took the engine to H&H and worked with Mike explaining the situation. What Mike found was the cam, the cam gears, crank gear and the distributor drive gear were not a good combination for this engine. (previous builder made the same mistake twice). The bolt on distributor drive gear adapter should have been drilled for an oil passage to provide the cushion and lubrication to the inside face of the timing gear cover.

The cam gear and crank gear were the later model that created a forward thrust. With using an early model cam and the distributor drive gear adaptor without an oil passage there was no cushion or lubrication between the end of the distributor drive gear and timing gear cover. Mike found a number of other issues with this motor and repaired them as required. The engine is back in the car for the 3rd time and all appears to be going well with a current odometer reading of 575 miles. All break in fluids have been changed and we are on the road.

Again, I want to, and do, thank everyone for your ideas, thoughts, inputs, questions, contributions of all kinds and support. A collective effort garnered a wonderful result.

Sincerely and Respectfully

Marc

[cadillac512]

That's great,Marc...glad to hear you're back going again.


Terry

[Desoto291Hemi]

Great job,,,,updating the final solution .
It’s always good to hear what fixed the problem.
Congratulations on getting it back on the road,,,,,,,many happy miles to you .

Tommy

[Harry Holst]

Ford Camshaft Endplay. Typically controlled by crankshaft & camshaft gear helix, pushing forward or backwards. Welding an aluminum nut to front cover and installing a bolt c/w locknut and adjusting enplay against distributer drive gear seems to be a resonable idea, any thoughts?

Sent from my SM-T713 using Tapatalk

[Ronnieroadster]

While we understand the early gears thrust towards the block easily seen during assembly and valve adjustments. I find once the oil idler gear and oil pump are installed the cam now thrusts forward. Its certainly not as much as the latter gears which we know thrust forward however there is a forward thrust even with the early gear combination.
Ronnieroadster

[Bored&Stroked]

Ronnie has it right. There will be some level of thrust backwards/forwards - even with the early cam/crank gears. Some of this can be attributed to how the cam was ground and the resulting interaction between the lifters and the lobe profiles and also whether you're accelerating or decelerating. This is also why it is important to check the final cam thrust and get it as close to .004 as possible (though not less than this).

I've seen plenty of situations where aftermarket timing cover gaskets were twice as thick as the originals, which adds a bunch of slop to the thrust - so I always measure my gaskets as well as tune the thrust.