Truck2007

Ï just re-checked each valve on the drivers side and #7 is at 1-1/8 turn on both, 5 and 3 are 7/8 and #1 is @ 1 exh. and 7/8 int. Ï will check the passenger side this week. All number of turns are to 22 ft/lbs.

2002_Z28_Six_Speed

iTrader: (20)

That sounds like a stupid short push rod length for low lift. But it's all about how the cam is ground. I would question it though. Did you measure the checker tool with some calipers as a sanity check? The stock springs might be good for what is normally a truck RPM. I don't rev out my motor that much and can probably get away with less spring. I have LS3 springs on my Tick cam and no issues.

Truck2007

Ï measured the PR checker at 6.805". Ï thought the same with the 7.300 pushrods. Ï have lost count on how many times I have checked pushrod length but I am in the range of 7.255" - 7.258" across all lifters at zero lash. Ï will be pulling the passenger side cover back off this week to re-check preload and run it with the cover off. Ï know I have some variation in preload on the driver side, .065 - .088, but it should be within range of the LS7 lifters. Ï will also be putting a straight edge across the valves to see if the heights are close.

madmann26

iTrader: (7)

Katech recommends .070 and BT recommends .100 preload.

Shoot in the middle and go .090 and see what happens.

You could also use a longer PR if you don’t go deep on the preload.

Truck2007

Ï have already tried 7.325". With those, it had a good idle but noisy over 1500rpm

Truck2007

Ï just rechecked the passenger side and the preload was .69" to .889" or 7/8 to 1-1/8 turns on the rocker bolt. One lifter had no pressure as it was being loaded. All values were at 22 ft/lbs. From the rocker bottoming out to torqued is about 1/8 turn.

1FastBrick

iTrader: (17)

This is likely the source of your noise.

You can try something like a quart of marvel mystery oil or even a quart transmission fluid and see if it clears up.

If it's not pumping up this is likely why its noisy.

Truck2007

Have you been able to revive a new, possibly defective, lifter doing this?

1FastBrick

iTrader: (17)

On Engines that have not been maintained, it's possible to get debris in the oil passage. Same if you do a head gasket job and contaminated oil plugs up the lifter.

On New Lifters. If the cosmiline is not cleaned off, they can stick. They can have the same issue and not pump up.

It's an old mechanics trick. The Trany fluid contains detergents that help clean. It's also thinner than the regular oil so it can get into smaller passages easier than regular oil.

Jeebalow

iTrader: (3)

Interesting, I hadn't seen anyone mention this. What's the proper way to clean off cosmiline? Do you disassemble the lifters and spray everything with brake cleaner then reassemble? I am putting an engine together and using Johnson 2110 lifters and want to make sure they don't have any issues. I also had a ticking noise with my "LS7" lifters in my current engine.