Stuck Lifter?

[69chvelle]

The "grease" on the plug are metal filings, which is normal. Get a filter magnet if it bothers you.

The pre-03 lifters are an inferior design, they are prone to rattling and once they start they don't stop. My oil looks clean enough that it may have well have just have come right out of the bottle, as I change it frequently, run seafoam in the oil before changes, and it never gets too hot because its winter in Fairbanks.

Early genIII lifters don't stick, they fail. Its generally benign mines rattled for the better part of 60,000 miles and she's pushing 122,000.

I'd be more worried about light brown oil, you've probably got coolant getting in somewhere.


That's my take on it.

The light brown was from running the Gunk Motor Flush through before the oil change. So, these lifters aren't going to break free, their just broke?

[stngh8r]

[txarkitekt]

I happened to be at a GM dealership last week and saw the cause of what you may be having issues with. I saw a GM factory cam where the lobe disintegrated and sunk down about .050" and the roller of the lifter was pitted.

I have seen that as well. Fixing this problem is quite tricky, but you have to address it correctly. I would honestly stop with all of the additives and oil flushes and go straight to replacing the lifters. Yes, its a PITA cause you have to remove the heads, but at that time (once the lifters are removed) you can look down the lifter bores to the cam and see if the cam lobes have excessive wear. To do so, remove heads, lifters, and lifter trays--then turn the crank so the cam spins--and use a flashlight to look down each lifter bore to inspect the cam lobes. They should be fine, but I have seen a lifter go bad, have the roller bearing on the bottom of the lifter mushroom, and flatten a cam lobe.

The light brown was from running the Gunk Motor Flush through before the oil change. So, these lifters aren't going to break free, their just broke?

A lifter COULD break apart, so I would go ahead and replace them right now and not jack around with anything else.

[stngh8r]

Well, if its stuck it might could break free, right?

However. If its broke, changing the oil few times and adding some solvents isn't going to make it any worse is it? I mean do you really have that much to lose?


IF its broke, sounds like a good time/excuse to do a cam swap.

[Maui4x4]

I have seen that as well. Fixing this problem is quite tricky, but you have to address it correctly. I would honestly stop with all of the additives and oil flushes and go straight to replacing the lifters. Yes, its a PITA cause you have to remove the heads, but at that time (once the lifters are removed) you can look down the lifter bores to the cam and see if the cam lobes have excessive wear. To do so, remove heads, lifters, and lifter trays--then turn the crank so the cam spins--and use a flashlight to look down each lifter bore to inspect the cam lobes. They should be fine, but I have seen a lifter go bad, have the roller bearing on the bottom of the lifter mushroom, and flatten a cam lobe.



A lifter COULD break apart, so I would go ahead and replace them right now and not jack around with anything else.

Id say go with Tyler's suggestion, pretty much going straight to the source without procrastination. Hopefully you dont have a worn lobe... this happened on my friends 99 5.3.