ryle

iTrader: (19)

I am just curious as to what I am doing wrong. This will be the third collapsed lifter in two weeks. I am running a car with the mods in sig. The lifters I have been using are stock LS1 lifters. they have been working fine up till now. Since the rebuild the engine has about 8-9000 miles on it. It seems like all my lifters are starting to go at the same time. Obviously I am puttig too much strain on the lifters, but I was just curious what causes a hydrollic lifter to collapse.

ss.slp.ls1

iTrader: (36)

That's odd, maybe you picked up a set of bad lifters. Your setup is not that radical. I would yank the rest of them out and throw in a new set of LS7 lifters. I would then measure for appropriate pushrod length again as LS7 lifters have been known to require a .05" different length pushrod.

ryle

iTrader: (19)

I knew I could count on SRJ for a fast response Could it be that the lifters I'm using are not rated for higher rpm? I'm spinning the motor to around 6500?

ss.slp.ls1

iTrader: (36)

I don't think that is it. I am spinning my LT1 lifters to the same rpm. What length pushrod are you using?

ryle

iTrader: (19)

I am pretty sure they are 7.200. honestly I don't remember, I have a build sheet but It's in storage. I have a set of stock LT1 lifters, but didn't want to use them cause I thought they wouldn't handle it. they have about 120k on them

ss.slp.ls1

iTrader: (36)

You can get LS7 lifters for like 140. I'd do that. I'd check your lifter bores to see that they are not rough or scored. They might need deburring.

ryle

iTrader: (19)

The damn lifters go under high rpm. each time that I have had a lifter go it has been just after I launch the car (car ran great BTW)

RamAir95TA

iTrader: (2)

I see you have an aftermarket Melling pump. Check to make sure that the screen isn't plugged and that the oil pickup didn't fall off. If oil delivery is restricted to the lifters (plugged oil galley or low oil pressure), the lifters won't "pump up" to take up the normal slack in the valvetrain.

ryle

iTrader: (19)

I just did a quick check and it appears that my pushrods are a little too long looks like I'm gonna end up with some new lifters and pushrods

ss.slp.ls1

iTrader: (36)

What do you mean by quick check?

RamAir95TA

iTrader: (2)

If the pushrods are too long, then the valve won't fully seat and cause a rough idle. Correct me if I'm wrong, but I'm pretty sure that can't cause a lifter to collapse, as the valve is on the operating end of the rocker arm.

ss.slp.ls1

iTrader: (36)

Well if it was really long, it could cause coil bind, but I think that would shatter a spring before it would collapse a lifter, but I've never been off on my pushrod length. JK, ryle
Look at the bright side, maybe you'll dyno more than 320 this time around.

ryle

iTrader: (19)

thanx bud, I needed that. I should have checked the length in the first place, but I was a noob and didn't know a whole lot about internal engine or valvtrain geometry. I just trusted the engine builder who did my heads on the pushrod length. This time around I'm doing it right. the only problem is that the washers on two of my SA rockers have some bad spots on them where they came down on the valve from it being too loose after the lifter collapsed.

ss.slp.ls1

iTrader: (36)

You mean the little washers that are on each end of the valve stem roller bearing? Are your rockers rebuildable?

ryle

iTrader: (19)

on Lt1's if the rod is too long it will fully seat, but the rocker will not be on the center of the valve as it should be. I am not sure the name for the design, but i know that the rockers aren't torqued down, but rather they are set to zero lash

ryle

iTrader: (19)

yes, those are the ones. I am not sure if they are rebuildable, It looks like the pin is a compression fit and pushed into place. they are CAT brand.

ryle

iTrader: (19)

as far a quick check, I colored the top of the valve with a marker, and then did a couple revolutions on the motor. The place that was wore off was low and to the outside of the head, which means that the pushrod is too long. correct length would be in the center of the valve stem.

ss.slp.ls1

iTrader: (36)

I remember the brand, I looked at their website and it doesn't mention anything about being rebuildable. Maybe it's time to get some Comp ProMags...

ss.slp.ls1

iTrader: (36)

There is a guy selling some used ProMags with 1000 miles on them for 240, you might be able to offer him 200.

https://ls1tech.com/forums/non-lsx-p...block-etc.html

Low N Slow

iTrader: (4)

You need to make a solid lifter or put in a weak valve spring to check pushrod length. Without doing it you are collapsing the lifter and can't get an accurate reading.