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I think I wiped out my GP2 cam........

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I'm kinda curious what kind of assembly lube you used, how long you ran with it (the assembly lube) in there, and how long the engine has been running period. In hours not miles.

What RPM did you break the cam in at?

Did you change the oil and filter right after breaking in the cam?

Did you install cam bearings?

How was the engine used prior to the "failure"?


Sorry about 1001 questions, but trying to get a picture here...

Hard to diagnose away from the patient!
 
To clarify a few points, I went to great pains to do the install of the cam correctly. Yes, the front of the engine comes off along with the head. That means everything. Referring to the Bentley manual, basically you strip the engine down to the bare short block, unbolt the engine mounts, lift the engine an inch or so and remove the cam through the grille opening. A real P.I.A.

When I installed the cam, every part associated with it was new. Since I had the oil pan off several times (new oil pump, new thrust washers) I took the opportunity to stare up into the abyss and check out the lobes of the camshaft, never saw anything that looked like premature wear. This all came as a complete surprise to me. I used the correct break-in procedures, the camshaft was well lathered with break-in lube, the proper break-in rpms and run time were observed, oil dumped and reloaded, etc.

Engine stethoscopes are something that I have used for years.

I think I would rate changing a camshaft as the single most difficult procedure on the entire engine as it is done with the engine in situ. And yes, what the heck was/is that clanking noise has got me more worried than ever. What if the cam is changed and the noise is still there? Bummer.

I don't want the advertisement for me car to read, "Ran when Parked."

And our annual New Orleans car show is in a month. Lookin like this will be the first one I miss in 8 years.
 
Dial indicator at the pushrod side of the rocker on another intake as a "base" measurement for full lift, then on the one in question will tell if the lobe is rounded.

With the way the others appear in the photo and knowing the valve adjustments were done by a meticulous dentist, I'm inclined to agree that the hardening process on that lobe was bogus. OTOH, misadjusted lash can have a "work hardening" effect on lobes, too, causing a delamination of the hardened surface. I just can't see that in this circumstance. Very frustrating, no matter the cause. I begin to fear buying ~any~ "new" parts to rebuild these old lumps.
 
Right, Doc. I agree with the part replacement comment.
Scary.

Bill: Of course I should have known you'd be well aware
of stetho approach.

Is it possible to place a sound byte on the Forum?
I can tell you, it if's a cam problem as you suspect,
it would sure be neat to hear what one sounds like.
There is no better value than experience, even if it
comes via cyberspace.

Really sorry, Bill. This sucks.
 
This is what is happening with the new EPA oils that are out . I had a engine with 1000 miles since overhaule that came in for an oil leak on the head. Pulled one of lifters out [not sure why] And it looked just like yours. Sent the cam and lifters to our cam grinder and the said that the oils and soft lifters were to blame.. We had them repair the cam. I bought new lifters had them hardness tested and sent them to Elign cams. Had the cam and lifters matched. All this and it can still happen. We need to really look at the oil we are putting in our cars. I have used Castol 20w/50w for long time but the oil analisis is low on zinc and Phosphorus. See if you can fix your cam, Replace your lifters and get back on the road. Hope for the best.
 
This does suck. Especially as I'm getting ready to build a new engine with that cam.

I was going to use my usual Castrol 20W-50W, but now I'm not so sure.
 
No problem using the Castrol oil, you just need to add a zinc/phosphorus additive like the GM product. I'm not sure you need to continue using it once the engine is broken in, but would wolkd be cheap insurance.

I too am worried about all this as I am re-assembling my 1500 engine. I am having a quandry as to what cam/lifters to buy.
 
When I built my engine I looked for an oil that had high enough levels of zinc and phosphorus. I have mentioned this before and I agree it sounds funny, but usually an oil that is recommended for farm tractors fits the requirements. It makes sense, they are not under the same restrictions as vehicles used on highways.

I then called oil companies and asked to talk to people that actually knew and could verify the levels.

I talked to a person in R&D at Citgo. The oil I ended up using that fit my requirements is CitGard 500 and I am using 15-40. But because oil formulas are changing rapidly I would suggest that anyone concerned do their own research. There was a thread about oil recently that was interesting.
https://www.britishcarforum.com/bcforum/ubbthreads.php/ubb/showflat/Number/420324#Post420324

Some say it does not matter what the level of zinc or phosphorus are, that is fine. After the rather large amount I spent on my engine I plan to make the best effort to protect that investment. Too me it is like taking the medicine or the placebo.
 
Hey Bill !! Bummer indeed.

No, I'm not gonna throw any comments about your engine
because I know almost zipsky about auto mechanics.

But a lot of help came my way when I posted a few short
video clips for the experts to listen to my engine problems.

Before you rip your engine apart, set your camera to video
and post the clanking sounds. The Pros will have a better
idea what might be going on with your engine when they can
listen to the clank.

good luck, buddy!!

d
 
Two views of bad lobe
lobe1.jpg

lobe2.jpg


One view of a good lobe

lobe3.jpg
 
There is no point in running the engine any more. The damage is done as shown in your pic's. It's not going get any better. I'm sure that it is not a problem with Richard's cam, He makes to good of a product and he is one of us. There were some lifters out that were not hard as should have been so anyone building an engine should make sure the lifters are the right hardness. There should be a small ding on the lifter done during testing. If there is no ding i would want to know if they have been tested or not. Also don't settle for random or batch ckecks.


Conan
 
Uck Bill, that sucks.

I reckon you'll be faster pulling the engine by the time you are done to fix it rather than trying to do it in situ..
 
Oh my stars!
I've never seen anything like that; it's like it has been galled from lack of lubrication; it will be interesting to see what the tappet looks like.
Can you tell if this is this the only lobe to go bad Bill?
Some metalurgical testing is needed once you get it all apart.
 
conan69 said:
There is no point in running the engine any more. The damage is done as shown in your pic's. It's not going get any better. I'm sure that it is not a problem with Richard's cam, He makes to good of a product and he is one of us. There were some lifters out that were not hard as should have been so anyone building an engine should make sure the lifters are the right hardness. There should be a small ding on the lifter done during testing. If there is no ding i would want to know if they have been tested or not. Also don't settle for random or batch ckecks.
Click to expand...

Good advice, but I don't think this is the case. If it was then the lifter would have failed (like a hole worn right through it) which I have seen happen. I've also seen lifters shatter, not pretty.

It looks like either an oiling issue, cam defect, or an issue with the top end of the valve train.

Check this out..
https://tonydrews.com/2007-8Rebuild/CamFailure.htm

My .02,

Not that it isn't obvious, but you have bits of metal in the motor. Something to consider...
 
conan69 said:
... There should be a small ding on the lifter done during testing. If there is no ding i would want to know if they have been tested or not.
Click to expand...

So that's what that little ding was on all of the lifters I just put in my TRactor engine. I was going to ask you guys about that, but now I have the answer. BTW, the lifters came from Ken at British Frame & Engine. They also have holes on the side near the bottom, which I assume is to provide more oil to the cam.
 
martx-5 said:
conan69 said:
... There should be a small ding on the lifter done during testing. If there is no ding i would want to know if they have been tested or not.
Click to expand...

So that's what that little ding was on all of the lifters I just put in my TRactor engine. I was going to ask you guys about that, but now I have the answer. BTW, the lifters came from Ken at British Frame & Engine. They also have holes on the side near the bottom, which I assume is to provide more oil to the cam.
Click to expand...

Ken is one of very few sources for good lifters for the Triumph motors. Most of the racing TRactor folk get their lifters from him.
 
As far as the cam being defective. A good metallurgist can determine the finish treatment of the cam. Not that expensive. A lot of machine shops can perform the rockwell hardness test.....
 
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