Just got a custom ground can from Jim Dowell at Racer Brown cams and that's what he sent with it. If he says use it it's good enough for me.

 

Clever fellow; that Jim

 

Congrats ... trust lifters & PRs are rotating on their own.

 

The #8 exhaust lobe is gone. Started ticking last weekend when I was getting ready to take it out, and I pulled the intake today and the lifter wouldn’t come out and has significantly less lift than the others.

 

Go to Hydraulic Roller Cam and Hydraulic Roller lifters.
Stop spending money on Flat Tappet Cams. GM did years ago.

 

The new cam was installed March 8th and you think you wiped a lobe already? Not buying that. Too soon, unless you drove across the country w/o any Zinc in the oil.
Just not going to happen.

I suspect # 8 Exh lifter was not primed fully when it was put into operation. Without oil inside the lifter collasped, valvelash jumped from zero to 1/8" just like that. And that is the noise you are hearing, loose rocker. Or, for some reason, it bled off and can no longer hold pressure.

Grab a hold of lifter with some type of pliers and get it out of its bore. I can't believe it will be concave that fast. Something else is going on here.

 

It is possible. But I would suspect the tappet failed also which MAY have wiped the lobe.
My close frend had his engine rebuilt. Ran fine on the test stand. Cam broken in. Engine back in car that week, Drove car very easy and with in 30 miles - ticking. Tappet came apart and lock ring was in the lifter valley. lifter was concave on cam side whch wiped the lobe.
Here's the pics we took of the lifter.

 

My XE274 broke in fine. Wiped in less than 200 miles. That was back in 2002. I have run roller cams since then.

 

That's a possibility. One thing I found out recently most if not all of the big cam companies have there off the shelf cams ground by a large cam grinding company used by the oem. That's not to say they don't do a good job I will let you put 2 and 2 together. Custom cams are different they still do there own in house.I don't know or think that is the issue.
I think most not all failures are caused by human error.my cam guy said once it's broken in run it don't baby it get that oil splashed up on it that's what it needs.

 

Of course it happens ... not enough of right kind of lube, failure to verify lifters are spinning, too much of a good thing in wrong places, incorrect lobe taper, incorrect lifter crown, too much / too little lifter-bore clearance, lifter bores not squared ... blah blah ... it can happen immediately or creep up on ya like a social disease.
Me thinks a big chunk of these failures are assembler/ operator error.

 

I went out there and tried to pull on it with some pliers but got nowhere. Maybe I could have tried harder and forced it out, but I don't want to damage the bore. Here are some photos of it on the base circle and its new max lift. It was not lower than the top of the bore when I put it in, and it's definitely not coming up as high as the rest. I can get a little more lift out of it if I rotate the lifter, but it's still no good.




When I started it last weekend, it didn't run very well, seemed like it had a miss. I setup the choke and it seemed better, and I let it idle a bit, maybe 10 minutes, while I looked things over and made sure I didn't miss anything before taking it out on its first drive with the new motor. Just as I was about to leave, it started ticking. Revving it a bit made the noise go away, but as it returned to idle it started to tick and it would come and go. Pulled it back in the garage, pulled the valve cover, my dad tried adjusting the lash but the noise wouldn't go away. Less oil was flowing out of that rocker than the rest of them, which I don't remember being the case when we primed it. It didn't seem like the rocker was moving less than the others, but I thought it looked like it moved a little less while it was ticking than it did when it wasn't. I figured a bad lifter was more likely, but it sure doesn't look like that's all I'm dealing with here to me.

 

At this point since you can't easily get the lifter out. I would be very leary of trying to force pull it out because you may score the bore.
Pull the cam. Knock the lifter down the hole. Bet the lobe is wiped.

You could always remove the snap ring and spring and plunger to get more grip. Maybe put the snap ring back in and use the ledge caused by the snap ring as leverage. But again you are taking a chance on scoring the bore.

I keep hearing horror stories about the current quality of Flat Tappet lifters. Look at the picture I posted, The snap ring was in 3 pieces in the lifter valley.
He did NOT get another Flat Tappet cam setup.

 

For a lifter to wear that rapidly shows issues elsewhere. Something is binding on that cylinders valvetrain. That's not normal. Even with tremendous valve spring pressure it would not wear that rapidly.

If you can, try to force the valve open using the rocker-arm. I would suspect a valve is not liking its valve guide. Check under the rocker-arm where the pushrod mates for unusual wear pattern. Disassemble the rocker-arm and inspect the rocker-ball. And when you remove the pushrod, roll it on a flat surface.

If a valve-stem is hanging up, that would explain a lot. It had a miss, you said.

If a poor break-in lube failed, there would be more than just one lifter damaged. On a good note, once you figure out the cause, just replace the lifter with a new one. Your cam lobes will be fine. As noted in post # 22.

Don't let people bad mouth you with a Flat Tappet cam. There are hundreds of thousands out there running just fine. Have one myself. Quality.
Keep working at it. Eventually the lifter will come out. Helps to have the cam lobe on the high side. Suspect everything from the lifter to the valvestem. Maybe even the spring.

 

Do NOT force smeared lifter upward ... it WILL damage bore ... you already have a problem; you don't have to make it worse.

And yes, if they're Not spinning they WILL wear that "rapidly."

 

I’m gonna pull the lifter out from the bottom. Whether or not the lobe is gone, I’m gonna have a bunch of metal shavings in there now, so I’m gonna pull the motor back out and tear it down again so I can clean it out. I don’t want to risk having more issues later by just changing the oil and lifter. I didn’t post this to this thread necessarily to blame the break in lube, but I figured I already have this thread going so I’d just update it. Maybe I made a mistake assembling it? Not sure. I’m having a hard time wrapping my head around the idea of the lifter being as bad as it is without the lobe being bad too.

 

There is always the possibility the cam will not come out. The oil pump gear and rear bearing journal have to clear the stuck lifter. The bad lifter appears to be way in the back.

You said the cam is Nitrided. The lobe should be fine in the short term is was run.
Back to the drawing board, good luck.

 

Good luck and I'd be interested if you post pictures of what you find in there.

 

I've never tried to R&R a cam bass ackwards ... "butt" ...
... cam tunnel's aft bore is covered by a freeze plug ... R&R plug easily w/ motor out.

IF the gear becomes an issue, perhaps pull cam out; butt first? Dunno, never tried it.

While cam is out (regardless if via fore or aft), IF #8 EX lifter won't come out bottom, perhaps you can reach thru aft opening w/ a small file and dress lifter's edges enough so it can readily be pulled from top without wrecking bore.

 

I'll post whatever I find in there. I hope HeadsU.P. is right and the nitriding saved the lobe. Not sure yet when I'm gonna do it, I'm not too excited about yanking the motor out again. I might take a couple weeks off, but maybe by next weekend the suspense will get to me and I'll want to work on it again.

 

I have heard good things about Nitriding. But few customers want to pay the extra $100 or so and wait for a backorder.

I don't blame you for not wanting to operate a engine hoist again. I would do whatever I could to avoid that. Maybe even dropping the pan for a visual of the cam / lifter from underneath. Then precede with common judgement. You can also turn the crank to put the cam lobe at the highest point on that lifter.

Bad lifter is in the back. So removal of cam out the back, if even possible would be worse trying to clear the other journals and 15 lobes.

If you can remove the lifter across from the stuck one, maybe you can get something in that bore to pry on the other lifter, gently. IDK
At this point you have no proof the lifter is mushroomed. You have no visual. The use of a dental mirror from a pharmacy may help you see what's going on, again going through the opposite side bore. Or, a inspection camera, maybe?
The lifter is steel the block is iron. Theoretically, the lifter will be damaged on removal long before the iron will. But before I pull the engine, I would grab the lifter like a bad aching molar with channel-locks or vise grips, twist and pull.