Just a dumb question. Since all the work was on the bottom of the engine, why did you even touch the distributor? No I have not read through all this thread.
'90s Chevy truck elusive engine knock. Rod/Main bearings, or what?
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To prime the oil pump and get a little oil circulating through the engine before I fired it up.
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I debated whether to tackle those valves, but since I had the covers off to make sure nothing in there was causing my knock, I decided to adjust them (snugged all and then did final 1/2 turn). Most were pretty sloppy, with the engine having 162K on it. I'm guessing adjusting worn engine valves vs a newer engine might have to be treated differently? In any case, if I have to pop the covers off tomorrow and untighten them 1/4 turn, I can.
Yeah, that's all that's really necessary for verification at this point. Should be a conical spray pattern, not dribbling or not spraying at all.
Just for clarity, you did not loosen them? They are hydraulic lifters so normal procedure would be to back off, tight until very slight resistance is felt in the pushrod spinning then 1/4 to 1/2 turn after.
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No, I did not loosen them, they were just loose/sloppy from wear. In any case, I see in the Haynes manual they can cause a no start issue if not adjusted properly. So, I may as well go check them out. That's the only thing I can think of why it will not start. Not much a problem to remove the LH cover, but the RH will require moving my AC compressor a little.
Two off the wall things to try. If you have access to a timing light, try using it to see if the timing is close. Then try setting the valves by just tightening them to when the push rods have resistance. Also check that the firing order is correct in relationship to the direction of the distributor rotation.
Thanks,
Andy
Thanks,
Andy
I just thought, when you tightened them down, did you verify each valve was closed by rotating the engine as needed? Or did you just tighten down all 16 where it sat?
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I adjusted them by turning the engine by hand 90 degrees at the time (around 2-3 full rotations). I only adjusted the loose rockers during each 90 degree rotation. I don't think each valve was seated using this method.
The 90/90/90/90 method works fine.
With all things considered at this point, may want to loosen them all and tighten them all down again, just to verify.
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I will. And, that's the exact video I used!
Heh, I’ve watched a lot of VGG the last couple of years so it caught me off guard to see a younger/slimmer version of him
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I backed off 1/4 turn on each rocker. Still no start, but, the engine is having more pushback in the cranking, not the high-pitched starter/engine whine I was hearing. Then, took another 1/4 off each. The engine sounds much stronger, as though the starter has to push harder now (more compression?). It was getting late, and the battery was getting weaker, so I stopped for the night. I think it's getting close to starting, will see how things go tomorrow, might take another partial turn off each rocker and see what happens. Thanks.
Really not important if the bottom assembly done "correct" etc etc. Did inframes on large trucks and heavy equipment, never did pressure prelube after the fact and never any issues.
If you weren't experiencing any valvetrain noise to begin with, then I think that you really didn't need to adjust them. Sometimes after an extended sit, the lifters will bleed down some and "loosen". This is normal.
Once you get it running and the lifters filled up, it would be wise to adjust them so that they're all uniform.
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Houston, we have lift-off! After getting the valves adjusted back somewhat, and flipping the distributor back 180 degrees, it fired up this afternoon. Had a CEL code 22 (throttle position), which I cleared out with a reset. So far, It's running great, and with 30+ minute runtime in the yard, there's no knock! Of course, I'll still be a little nervous about the knock returning until I have a few highway miles on it. Oil pressure is very good, warmed up it's getting around 25 lbs idle and 45-50 at 1500rpm. Painted the valve covers while I had them off. Thanks to "everyone" for walking me through this endeavor, I really appreciate it! And a special thanks to my dear wife, as she helped install the oil pan and much more! Question, with all the failed cranking attempts, how soon should I change the oil & filter?
New bearings, and some unknown amount of gas? How does the oil smell and look right now?
My thinking, adjust the valves, address the other issues, maybe change in 500 miles (or less). I'm not sure that the bearings need break-in but if it was me, and if it was me I'd be running cheap oil--I'd probably do a drain and fill (maybe reuse the filter) now, and another oil change after 1,000 miles.
Congratulations.
Personally id treat it like a cam break in due to it being open, id probably change it now, and again in a couple hundred miles and then go normal intervals.
Just gets any stray debris or coolant or fuel out.
I basically never open an engine and not change the oil nearly immediately (30 minutes to an hour run time) and then access if another short change is needed based on scope of work and if i see anything odd in the first change.
Its not so much about "break in" as it is about the introduction of contaminates into the open engine.
I admit i have basically no support for this other than its what i always do.
Personally id treat it like a cam break in due to it being open, id probably change it now, and again in a couple hundred miles and then go normal intervals.
Just gets any stray debris or coolant or fuel out.
I basically never open an engine and not change the oil nearly immediately (30 minutes to an hour run time) and then access if another short change is needed based on scope of work and if i see anything odd in the first change.
Its not so much about "break in" as it is about the introduction of contaminates into the open engine.
I admit i have basically no support for this other than its what i always do.
I'm still mentally noodling over why the rockers/lifters were apparently over tightened using a standard method and caused the valves to hang open. After he loosened them back up, all good.
Any thoughts by chance? Just lifter bleed-down occurring as @The_Eric mentioned?
My best guess is that the lifters had bleed down as Eric suggested and they were not actually loose. He tightened them and then when the engine was pre-lubed they pumped up and the valves were then staying open.
Im almost always dealing with non-factory cams so I tend to do each cylinder at TDC, though i agree the method used should work more than fine on a factory cam on a non-high performance engine.
