1993 Yukon crate motor hydraulic roller lifter cleaning and adjustment journey - (Solved)

[Hipster]

I've seen lifters squirt, but it's quirt , squirt, squirt. Never a constant stream just rolling out of them, inconsistent from one to the next as well. I'm hearing something in the video, I hear a little tap, like maybe the valve adjustment is not quite there, but a little something else as well, just want to throw this out there, you say chirp in the video, but I've heard head gaskets give a little whistle/chirp when on it's way out. maybe a vacuum leak somewhere?? I didn't read through all of this so not sure what's what.

 

[tayto]

seems like way to much preload...i remember doing this on my caprice almost 20 years ago shop manual says 1.5 turns after zero lash. it ran like absolute garbage, i ended up setting them at 3/4 turns and now I do 1/2 turn on stock GM stuff. you might have a little noise but worth it for gain in power IMO.

I hate to say it, but this is why most of us just put new lifters in vs cleaning them. There has been a ton of labour and time spent here, not that wasted time is bad (if you learn something). I remember reusing lifters when you could actually find a low KM engine easily. But now? I wouldn't waste my time... Yes you cleaned them, but did you measure them? just because they are clean doesn't mean they aren't worn. this sounds like worn lifters and/or cam bearings to me.

 

[scott2093]

I can't imagine that my accidental starting of the truck last night without the drivebelt and hearing every lifter in the motor tapping like crazy even with what must have been a full turn preload isn't a clue. I'm not sure if they would have cleared up after a minute or two but they were tapping for a long time. When I put the drive belt on, only 2 taps at startup like it has been doing...

Sure seems like it's pointing to something...
Really wish I had know about taking notes when I started all of this. I must have read 30 different threads about adjusting preload and not one ever mentioned the benefit of taking note of how many turns it took to loosen them to get to just past zero lash in order to find home base if ever needed.
It sure would have helped me to do that in the beginning....
the poor man's version of knowing what lifters and cam you have....

"Not enough preload/spring pressure can cause the lifter to smack the back side of the lobe on its way down" is noted
I've read 22ft lbs...some lifters really need to be a turn and a half to 2 turns...and everything in between....

At least knowing where I started, I'd know kinda what the original builders or whoever installed it were at....

All I have to go off of now is a random picture of the threads showing above the rocker nut before I ever messed with the lifters and a picture of what the threads above the nut look like with what I believe to be a full turn past zero.

I'm going to pull all the rods and check them again for straightness, and document all the surfaces of the rockers etc....
then set them cold...see what it looks like...again...

really...1.5mb too big?...

 

[Hipster]

You sure this engine was mechanically healthy before you started with the lifter cleaning? As has been said about the lifters, sometimes stuff just wore out, sometimes opening a tired old engine is opening a can of worms.

 

[scott2093]

You sure this engine was mechanically healthy before you started with the lifter cleaning?

I really don't know....
It's a truck I bought 10 15..ouch ...years ago from a friend. A few years prior he had the motor replaced with a crate ... Transmission rebuilt.... I haven't done the math on mileage but I think it's worth not giving up on and keeping it going as is for as long as I can. That and I have a healthy disdain for landfills no matter how small....
Seminole/Creek roots maybe....
Wish I had taken interest in this stuff a lot sooner....

 

[scott2093]

So just putting everything at #1 tdc and loosening all the rocker nuts from GM manual...1 intake/exhaust, 5 intake etc... I was able to see that they were in fact at 1 full turn past zero lash to get them just past. Give or take a 16th or 1/8....just as I had noted..

Hot running adjustment works imo. I've added from and taken from turns at will after a hot running adjustment and noted everything and verified so far that it's where I thought it should be...

anyway, I thought it would be interesting just to preload number 5 intake while at this tdc... Here's 1 1/2 turns and 3 turns..lol

Looking at my previous thread count from before ever touching the lifters, it's clearly at least one full turn....Maybe even 1 1/2 turns...2?

Are there known stories of roller lifters that just work better at a turn and a half? more? Keeping in mind this is probably 2002-2005 ish timeframe motor....obviously don't want to bend rods...

 

[Scooterwrench]

No way of knowing what total preload you can run those lifters at unless you take them out and measure the total plunger travel then set them at 50-80% of that reading. My recommendation for you at this point is get another set of lifters and start over.

 

[scott2093]

get another set of lifters and start over.

Would I have to know what cam is in there?
193 heads
638 block is all I know...

 

[Scooterwrench]

You have two choices, rollers or flat tappets. You've had them out so you know.

 

[scott2093]

You have two choices, rollers or flat tappets. You've had them out so you know.

I see..Thanks...
any recommendations ? Does push rod length come into play anywhere?
Sorry for my ignorance...Figuring things out as I go