alconk

Two and a half yrs ago I replaced the upper end on my 82 Corvette with Edelbrock heads, cam, rockers, lifters ect. and have about 1000 miles on them. Still the Crossfire setup. So the other day I drove it and noticed a slight lifter noise, came home pulled the valve covers and gave the rockers (Comp roller tip 1.6) a quarter turn and left for work. Today I get the valve covers put back on and as soon as I started it it was very noticeable lifter clatter. I drove it around the block hoping it would go away but did not.

Tonight after work I pulled the valve covers and #4 intake rocker was extremely loose so I pulled the rocker off and the ball end of the pushrod was gone. Ended up pulling the intake and found the pieces but the lifter retaining ring was gone and when I used a magnet to retrieve the lifter it pulled the guts out but was able to remove the whole lifter. After checking the others I noticed #1 exhaust was the same way?? Removed the pushrod and the ball end was still stuck in the rocker and the lifter was also coming apart?? What's causing this??

I found all the pieces except the retaining rings the holds the lifter guts together so I'm assuming it's in the pan. First I need to know why and second what needs to be done? Would the cam still be ok and if the retaining rings are not in the pan then what?

I can post pictures if needed. Please help. Thanks!

76Rat

The why is, you did not upgrade the pushrods to handle the extra lift and spring pressure when you installed heads with the 1.6 rockers.

The snap rings in the pan wont hurt anything.

Replace the lifters and all of the pushrods with good one piece hardened push rods, (not stock) Check your rockers for damage and replaced accordingly. Hopefully this will be all that is screwed up and you will be good to go.

Good luck.

alconk

That's it though the pushrods are hardened Comp Cams. Do you think the cam is ok?

lionelhutz

Check the bottom of the lifters. If they are still convex then the cam should be OK. If they are flat or concave then the cam needs to be replaced.

They could have come apart because they didn't have the proper preload.

MotorHead

Those pushrods with the ***** on the end are junk and wear down fast, ask me how I know

alconk

You were right! I thought I replaced them with hardened ones but nope. Thank you!

alconk

Yep that's what Comp Cams said. Bottom of the lifters are flat but they were when installed. ?

alconk

Agreed! Learning pushrods 101 today.

MotorHead

Hard to tell when installing them especially when you are not looking for that. A straight edge or glass table works.

lionelhutz

They appear flat if you just casually look at them but they should have a slight convex. Check them with a straight edge.

427Hotrod

Those little wire clips in the pan can definitely cause trouble. Most likely they will end up inside the oil pump and lock it up instantly. You need to find them. I've seen it happen more than once over the years.

JIM

CanadaGrant

With the Comp wire type retainers in the lifter, if you get any sort of slack in the setup due to wear or adjustment problems (premature wear in your case) the lack of downward pressure on the pushrod cup will pound out the thin wire retainer in just a few miles. With the lifters adjusted correctly the pushrod cups don't even touch the wire retainers so your lifter retainer failure was caused by pushrod failure. You should check the pan for those retainers or worse, retainer pieces....

cooper9811

I agree. A few years ago, I broke the trunion clip from a roller rocker on a 406. The clips not only got into the pan, but on thoier way down, likely bounced off of a connecting rod and ended up scratching the crap out of a cylinder wall.

I would pull the pan and have a look at everything.

cardo0

Yes you need to pull the lifters and inspect. But I expect the worse now.

I don't know how to say this w/o insulting you but blindly adding lifter preload tells me you really don't know what can happen to the entire valvetrain when you bottom out the plunger in the lifter. I now suspect you didn't adjust the preload correctly to begin with. Broken push rods and broken lifters blamed on bad parts is possible but usually just an example of denial.

But please prove me wrong and show us pix of the lifters still in convex shape. I can't preach proper methods for setting preload on this forum enough. I'm sure others are just as tired of my rants as I am.

cv67

Get some Manleys no more pushrod problems. They make good stuff.
Get it all back together make sure they are adjusted 100% see if the ticking starts again.
Sure wish GM made their good flat tappet lifters still.

alconk

Hmm... brutal! I will take this as a learning experience but these have been in there for 2.5 years. The reason I gave it another 1/4 turn in is originally when I set the lash I only went 1/4 turn after 0. I read and was told to turn a full half turn past 0 but said if you could get by with a 1/4 it would be better .

I spoke with Comp Cams and told me stock pushrods will eventually fail with a aftermarket cam and higher valve springs. When I told him about the lifters he said he wasn't surprised and have seen the same scenario and explained why and made sense to me.

I pulled all of my lifters and they are flat on the bottom with no markings, I asked three different Comp Cam Techs and every one told me they are suppose to be flat. All that happen to the lifter was the retainer spring came out.

Thanks for your input though that's why I post questions.

alconk

Ok I'll check. Thanks.

alconk

Exactly what Comp told me. Thanks!

63mako

If the lifters are not slightly convex they will not rotate and take out the cam lobes and likely all the bearings with them in a very short time.

lionelhutz

If they all appeared the same then you should be OK. Just make sure they go back where they came from and you don't mix up the locations.