I put a motor in my t/a last summer (forged iron block 370, stock untouched L92 heads, LS3 Polluter cam, LS7 lifters). I drove it for almost 3,000 miles and had cyl 3 exhaust lifter collapse on me. So the next night I went to the dealer, bought a LS7 lifter, and changed it out. Drove it maybe 20-30 miles and had the lifter I just replaced collapse. I put it in the barn and lost motivation to fix it. So fast forward to now. I bought a set of Morel 5315 lifters and am going to replace all of them. When I put the motor together the first time, I did not check push rod length. I just bought a set of 7.425's for it and tossed them in (stupid, I know but I was in a hurry to get it running.) So I'm wondering what my problem could be. As of right now, I am assuming I have a preload issue causing it.This time I bought a push rod length checker and I checked cyl 1 exhaust push rod length. I took the size of the checker with zero lash (7.371) and divided the push rod size I put in there ( 7.425.) I came up with having .054 of preload. Did research on here and some say I should be around .080 for preload but it seems like some people run the LS7's at .050-.060 preload. So can I get some opinions please? lol I don't wanna completely eliminate the lifter not getting oil, but it was covered in oil and the lifter isnt blued like if it got hot from not getting oil. The first lifter, the cup the push rod sits in was sideways. This lifter I just pulled out, looks normal.

Also, I took a straight edge across the valves and on all the exhaust valves, I can stick on .010 feeler gauge between them and the straight edge.

Just looking to vent and maybe get some feed back. I plan on having the heads back on Saturday and measure push rod length then with the new lifters. Thanks in advance!

 

.080 is to much for the morel 5315's. You want them in the .040-.060 range. The 5315's have a smaller preload range than the LS7 lifters.

 

The 5315 has between .139 to .141" of travel.