Check this out ladies and gents, 1981 corvette with sbc 350 totally rebuilt with these specs:

9:8:1 compression
Trickflow aluminum heads with maximum valve lift of .520 part#30410001
Lunati Cam/wlifters hydraulic flat tappet max lift at valve .489int/.505ex part #10120703
Comp cams roller tip rockers with pushrods 1:5:1
Valvetrain adjusted until the roller is dead on the center of valve with correct length pushrods
after break in adjusted while running to 1/2 turn after "clacking"
Edelbrock performer rpm air gap
demon 650 vac secondary
373 gears
2004r transmission with 2300rpm stall

Car will run like a bat outta hell, ridiculous fast and fun until a ticking noise, sounded like a lifter issue and upon examination a pushrod tip was completely broke on the top of the exhaust side of cylinder three kind of like the ball broke off of it and there was a small piece of spring retainer that sheared off of the valve spring.
I then decided to take the engine down to see what the problem is and discovered that the exhaust lifter looked like picture submitted, where there is an obvious circular looking wear mark on the bottom of it

What could have caused this? Faulty lifter? Bad Spring? I don't get it, and do not want this to happen again after I put everything back together. Anyone's help is definitely appreciated!

 

You might want to pull the cam. I think you wiped a lobe.

 

I did, the engine had about 500 miles on it and I never went above 5000 rpm.....I just do not understand what caused it so I wont make the same mistake again, this is the only one that is like that.

 

Caddy 4100's did that in the 80's due to poor no oil flow on one lobe/ lifter

 

Do you think it could be from a high volume oil pump? I was told that too much oil pressure might not lube the rockers properly

 

you may have some blockage in the oil galley to that lifter, or just did not break in properly/wrong oil. in this day and age, not running a roller cam is a gamble.

and high oil pressure would not have anything to do with it.

 

I would like to add to what was said about break in. I follow the break in instructions but they don't tell the whole story.
The lifter has to spin in it's hole (rotate) to properly break in. I found a lifter that failed that did not spin and you could see where the cam lobe cut a groove right down the middle of the lifter. What I do now during lifter installation is make sure each lifter spins freely in it's hole.
Case in point was a engine I had cleaned and inspected for cracks here in town by a well known shop. Not only did they miss the long crack just above the lifters but almost every lifter was hard to install due to whatever they used to clean the block. Only a few would rotate in their hole. I had to hone each hole to assure rotation. That is easily done with a lifter removal tool.

Dom

 

Hi Dom, would never recommend/use a "lifter-removal-tool", you risk further damage to the lifter bores. Not worth it!

Defective lifters are always best removed from the bottom side of the lifter bores! Can be done fairly easily on an assembled unit!

Thanks, Gary in N.Y.

P.S. Here's a "tip" that should be followed after the initial break-in period, simply remove the valve covers and make certain ALL 16 pushrods are spinning. They don't need to spin fast, but they MUST be spinning! If not, a problem will surface later!

 

Cam is gone. Need cut filter open and check it for particles. A good idea is to drop the pan and check the bearings to see if they have seen any debris.

 

These types of stories caused me to no longer use flat tappet cams.

 

The lifter tool I use takes the place of your fingers.

 

Switch to a roller and save yourself a ton of grief vs. a flat tappet. You will not have to worry about flatting a cam anymore because you didn't use the right oil with more zinc. VERY common issue now a days. Good luck and hopefully the motor isn't hurt.

 

If going roller, dont forget the dizzy gear and cam button

 

Hi Mike, if the OP chooses the retro-hyd platform and works with an excellent/top-notch shop he can ELIMINATE the need for any cam buttons (includes setting cam end-play) AND special distributor gears OR even the fuel pump pushrod!

We use all the OEM factory pieces now on just about every 100% stock-appearing unit we build! The "late" style cam thrust plate from the OEM roller blocks now get used on the early platform. Works like a charm!

Thanks, Gary in N.Y.

P.S. We've done numerous builds as of late with this setup, but the block requires some add'l machining! No big deal here now! Here's a shot of a finished setup on an early 400" SBC!