RX-Ben

iTrader: (7)

Hey guys. I found this lifter in my LS-1. It looks like it may have a problem mating with the cam. What do you think?

Thanks
Ben

Ojustracing

iTrader: (4)

where did the rest of the roller go?????

Ben I take it you didnt make OLOA 05 with the car. Seeing that registration is tomorrow, Hopefully next yr then. later John Oliver

RX-Ben

iTrader: (7)

Good question. I went to sleep last night after finding the broken lifter. I found a couple roller bearing looking things in the valley and a miscellaneous small chunk of metal in there as well.

The exhaust valve that it was mated to is toast, there was some p-v interference, and the cylinder walls are pretty scored for some reason.

It was the final tuning session before I headed out to South Bend, so no One Lap. I have a lot of spares for the car, but not a spare engine ready to drop in.
It particularly sucks b/c I'm going to law school next year and I won't be able to do One Lap for the next three years unless they move the date. Damn.

Ben

RX-Ben

iTrader: (7)

After doing a bit of reading, it sounds like maybe the lifter turned.

Anyone know if anything I can do to make sure this doesn't happen in the future?

edit: The lifter cup was in fine shape and there is no way that the lifter could've turned. Looks like it was just some crappy metallurgy.

Thanks
Ben

crainholio

iTrader: (2)

What brand were the lifters?

I've got a shortblock ready to go together here and I'm lifter shopping, this failure is of interest to me...PM please if you don't want to post the mfg name in the open.

RX-Ben

iTrader: (7)

They were stock lifters with 20K miles. I called up a number of shops and that is what they recommended with my proposed 6800rpm redline.

I am pretty confused as to why this happened. Lifter pre-load was spot on (about 1 turn to 22 lb/ft), springs were up to the task (Patriot Duals), I spun to about 6K and then 45 seconds later (low rpm driving too) I heard the noise of the lifter parts being tossed around. There was never a hint of valve or valvetrain float and no indication that something was actually going bad until it was way past the point of no return.
Rocker arms are in good shape and all the other lifters/valvetrain parts seem good.

I have a hard time believe that a seasoned part would suddenly fail.

Thanks
Ben

RX-Ben

iTrader: (7)

I dropped the block off at machine shop to see if it is salvageable, I'll know in a couple days. I talked to the shop owner and he pulled out a lifter that lost its needle bearings (in his $18,000 engine), much like mine did. From the damage on my lifter it is pretty obvious that the needle bearings fell out, then the roller was jammed against the lifter body for a while, and finally the "ears" that hold the roller pin failed. He said that lifter issues like this aren't too uncommon and that the lifter is definitely the weak part of the valvetrain because of the needle bearings and lack of forced oiling at the roller/cam interface.

I guess the lesson is if you are rebuilding an engine- make sure you meticulously clean the needle bearings, thoroughly lube them (soak in oil for a while), and then pray.

ben