clemsondave

Exactly our delima.

Description of what we are seeing:
manually crank motor until the springs are compressed.
within 10 seconds or so, the springs open up - pushing the lifters down. Or, the lifters are falling allowing the springs to open.

what we are trying to figure out:
are the lifters giving out? or,
are the springs too heavy and pushing the lifters down?

1FastBrick

iTrader: (17)

I think the issue is with the Lifters and not the springs. Also if you have to open it back up. Replace those trays, even I didn't know they were so cheap... I think there like around $3 each from SDPC. I have heard of so many issues with those stupid things...

BTW were did you get your lifters from??? What rocker arms are you using...

clemsondave

I'll replace the trays if we go back in. Got a part #?

Using the old rockers. They looked at them pretty close and all looked fine.

Got the lifters from gmpartshouse. They came in a sealed GM box. Do you think they are just bad, or the wrong ones for this app?

1FastBrick

iTrader: (17)

Good! That means the lifters have the standard GM parts warranty of 1 year... maybe they were made on friday or a monday shift if you know what I mean... If you do have to go back inside. I would see if they would at least give you a little better discount since you have to do the job twice... I think the stand up thing would be for them to give the extra needed parts at just above there cost...

#12551162 -Lifter Guide, LS1/LS6 SOLD AS A SINGLE
you will need 4 obviouisly...

clemsondave

Should the LS7s be ok? I'm sure I am not making more power than an LS7 block. I'm thinking about just going with comp cams lifters just so I won't have to do it again.

Discount and free head gaskets would be nice.

1FastBrick

iTrader: (17)

I wouldnt think they would be a problem... The only thing I would think is the stupid plastic trays are on the lose side being that old with that many miles... My bigest fear is that they would eventually turn side ways in the tray. plastic parts wear out to with heat cycles and become brittle over time. i just sold a used short block to a guy that had 3100 miles on his build up... for some reason , the cam bearings spun #3 being the worst and ate a lifter, damaging the block... It was cheaper to buy my short block, sell what he didn't need out of it to offset the cost of remachining it to work with his other still fairly new par rather then have his damaged block re machined...

clemsondave

I agree, silly not to replace them. We didn't really think about it b/c when we disassembled the block, we played around a bit. I might be adding a cam to the vette this year, so we wanted to try the trick where you spin the cam so the lifters stay up in the trays, then insert a rod to hold them up while you remove the cam. All that worked perfectly, so we didn't see any issues with the trays. The held the lifters.

Thanks for all your help. I'll let you know what happens from here. As much as I don't want to spend more $$$$, I am even more tired of screwing with this. We'll probably toss in whatever lifters/springs/rods Comp suggests. I was shocked that with the combined 60+ years of experience of the two guys that came over last night, neither had seen this. They work daily on everything from tractor to race motors. Both worked for quite a while on race teams. One the round and round type, the other drag.

clemsondave

We spoke with Comp. They think it is bad lifters. Since that is the consensus, looks like we have to get messy again.

Also ordering the correct pushrods, head gaskets and lifter trays. Comp says use .020 to .040 preload. So, we're going with the 7.300s which will give me .025 preload. All three of us measured it and got the exact same number - 7.275 at zero lash. I guess that means the ticking is either the lifters falling or the rockers tapping the valve covers (forgot to look last night) because the PRs are too long.

the question of the day is, do I take a chance with LS7 lifters again at $122 or go with Comp lifters at $245?

budhayes3

iTrader: (19)

Wow man, it sounds kinda crazy that a whole set of lifters would be bad, although there are bad "batches" of parts out there. I'd go with the LS7 lifters as they should be more than adequate...hopefully you'll have better luck with your next set if you do go with them.

negativeswitches

iTrader: (15)

correct me if i'm wrong but didnt you run the motor with the valve covers off and still hear the noise?

how ould the noise be from hitting the valvecovers