clogged lifters or needing adjustment?
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Joined: Feb 2011
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From: charleston sc
clogged lifters or needing adjustment?
Hey guys, im posting this for my truck because i cant get any answers from the truck forums and you guys are, by far, THE BEST.
I put heads on my 5.7 ltr after it ran hot. like a fool i did not replace the lifters/pushrods. I went to*adjust the lifters*while the motor was running and noticed that three rocker arms on one side had very little oil flow. Also no oil pressure is registering on the dash, but i thought it was only the oil sending unit. I havent done the final lifter adjustment while running. I did adjust them by the book but i think i torqued a few too much.
Is the low oil flow due to those lifters being overtorqued?
or Does this mean ive just got clogged lifters?
Can i just replace those lifters that have low flow?
Will an oil additive clear them up if i let it run or drive it gently? Im scared to let it run even to adjust them to find out.. Advice.. please...
I put heads on my 5.7 ltr after it ran hot. like a fool i did not replace the lifters/pushrods. I went to*adjust the lifters*while the motor was running and noticed that three rocker arms on one side had very little oil flow. Also no oil pressure is registering on the dash, but i thought it was only the oil sending unit. I havent done the final lifter adjustment while running. I did adjust them by the book but i think i torqued a few too much.
Is the low oil flow due to those lifters being overtorqued?
or Does this mean ive just got clogged lifters?
Can i just replace those lifters that have low flow?
Will an oil additive clear them up if i let it run or drive it gently? Im scared to let it run even to adjust them to find out.. Advice.. please...
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
Yikes, you might be in trouble. Lifters are not adjusted by torquing them. The preload is adjusted by turning down the bolt holding them in place by a certain amount when the lifter is on the base circle. Hopefully you did this
Team Owner
Joined: Oct 2004
Posts: 81,241
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From: altered state
St. Jude Donor '05
Back them off and start over. If you have no/low oil pressure you may need to get some rpm up before it starts spitting out like it should .Hopefully its not too damaged
Never heard of a clogged lifter
Is the low oil flow due to those lifters being overtorqued
what does "torqued" mean, how did you adjust yours?
Thread Starter
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Joined: Feb 2011
Posts: 75
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From: charleston sc
I did adjust the rocker arm lash by the manual. however i think i tightened some of them down too much
or
while i was working over the motor, i let trash get into the lifter heads.
My main question i guess is: would tightening the rocker arm down too far cause the lifter to not allow sufficient oil to flow to the top of the rocker arm?
Whats confusing is, some of the rocker arm oil ports are peeing oil just fine, leading me to believe i have sufficient oil pressure. The ones that arent peeing well i believe may have trash in the top of the lifter, where the pushrod sits.
or
while i was working over the motor, i let trash get into the lifter heads.
My main question i guess is: would tightening the rocker arm down too far cause the lifter to not allow sufficient oil to flow to the top of the rocker arm?
Whats confusing is, some of the rocker arm oil ports are peeing oil just fine, leading me to believe i have sufficient oil pressure. The ones that arent peeing well i believe may have trash in the top of the lifter, where the pushrod sits.
Burning Brakes
Joined: Mar 2004
Posts: 1,108
Likes: 4
From: Plano Texas
ninjaneer911,
With your lifters on the base circle of the cam, tighten the adjuster nut 1/2 to 3/4 turn to preload them. Of course, you want to spin the pushrods with your fingers and make sure that all up and down movement is gone before you preload the lifters. To clean out your engine, an old practice that works well is to drain about a quart of oil out of your crankcase and then add a quart of transmission oil to your motor oil. Then drive your car 2 to 3 days with this combo in the crankcase. Then drain out the oil, replace the filter and add new oil and filter. The transmission fluid is an oil but it has a lot of detergent in it to clean parts and keep them from sticking. It will also dissolve any sludge and clean out passages that may be preventing oil from getting to your lifters. Another good substitute for transmission oil is Marvel Mystery Oil. You can buy it at any good auto parts store. Good luck.
Coves4Me
With your lifters on the base circle of the cam, tighten the adjuster nut 1/2 to 3/4 turn to preload them. Of course, you want to spin the pushrods with your fingers and make sure that all up and down movement is gone before you preload the lifters. To clean out your engine, an old practice that works well is to drain about a quart of oil out of your crankcase and then add a quart of transmission oil to your motor oil. Then drive your car 2 to 3 days with this combo in the crankcase. Then drain out the oil, replace the filter and add new oil and filter. The transmission fluid is an oil but it has a lot of detergent in it to clean parts and keep them from sticking. It will also dissolve any sludge and clean out passages that may be preventing oil from getting to your lifters. Another good substitute for transmission oil is Marvel Mystery Oil. You can buy it at any good auto parts store. Good luck.
Coves4Me
Drifting
Joined: Feb 2003
Posts: 1,614
Likes: 163
From: Davis CA
Please backup.
Clearly, you do have oil pressure if you've got flow up the push rods on most cylinders. Are the non flowing rods "randomly distributed" or all together? I'm going to assume that they are random. If they were together, I would be more concerned.
It is unlikely that the hollow rod is blocked but lifters can be forced to bleed down by over-tightening and I'm not sure about the consequences. You don't mention your rockers and that can make a big difference. It will be easy to see the consequences of adjustment when you do the next step.
If it were me, I would pull the covers and adjust the rockers with the engine running. That might take care of everything. Please do the running engine adjustment and then report back.
When I did this step, I bought cheap covers at Autozone and cut them to become oil catchers. It was only about $25 for the chrome "dress" covers. You would be welcome to mine if you were near Sacramento.
Clearly, you do have oil pressure if you've got flow up the push rods on most cylinders. Are the non flowing rods "randomly distributed" or all together? I'm going to assume that they are random. If they were together, I would be more concerned.
It is unlikely that the hollow rod is blocked but lifters can be forced to bleed down by over-tightening and I'm not sure about the consequences. You don't mention your rockers and that can make a big difference. It will be easy to see the consequences of adjustment when you do the next step.
If it were me, I would pull the covers and adjust the rockers with the engine running. That might take care of everything. Please do the running engine adjustment and then report back.
When I did this step, I bought cheap covers at Autozone and cut them to become oil catchers. It was only about $25 for the chrome "dress" covers. You would be welcome to mine if you were near Sacramento.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Hey guys, im posting this for my truck because i cant get any answers from the truck forums and you guys are, by far, THE BEST.
I put heads on my 5.7 ltr after it ran hot. like a fool i did not replace the lifters/pushrods. I went to*adjust the lifters*while the motor was running and noticed that three rocker arms on one side had very little oil flow. Also no oil pressure is registering on the dash, but i thought it was only the oil sending unit. I havent done the final lifter adjustment while running. I did adjust them by the book but i think i torqued a few too much. Why do you think that? did you do something thats not in the book?
Is the low oil flow due to those lifters being overtorqued? no such thing
or Does this mean ive just got clogged lifters? no such thing
Can i just replace those lifters that have low flow? Who says you have oil pressure? if you only get oil from some rockers...there is a mechanical problem, nothing that STP is going to fix. Accept that there is no short-cut.
Will an oil additive clear them up if i let it run or drive it gently? sure...and then you'll have 16 that aren't getting enough oil. They're cheaper when you buy other internal parts as a rebuild kit.
Im scared to let it run even to adjust them to find out.. Advice.. please...
I put heads on my 5.7 ltr after it ran hot. like a fool i did not replace the lifters/pushrods. I went to*adjust the lifters*while the motor was running and noticed that three rocker arms on one side had very little oil flow. Also no oil pressure is registering on the dash, but i thought it was only the oil sending unit. I havent done the final lifter adjustment while running. I did adjust them by the book but i think i torqued a few too much. Why do you think that? did you do something thats not in the book?
Is the low oil flow due to those lifters being overtorqued? no such thing
or Does this mean ive just got clogged lifters? no such thing
Can i just replace those lifters that have low flow? Who says you have oil pressure? if you only get oil from some rockers...there is a mechanical problem, nothing that STP is going to fix. Accept that there is no short-cut.
Will an oil additive clear them up if i let it run or drive it gently? sure...and then you'll have 16 that aren't getting enough oil. They're cheaper when you buy other internal parts as a rebuild kit.Im scared to let it run even to adjust them to find out.. Advice.. please...
AFTER you establish that there is adequate oil pressure to do those 2 things, THEN you can go back, loosen them all, and adjust until they are tight enough that you can barely rotate the pushrods with your fingers. You may want to go ahead and remove the pushrods to check for straightness if you THINK that you over-tightened. Better to find out now that later when one breaks and destroys the motor..again.
They are only $2 each..
After the manual adjustment then start up and tighten ONLY the noisey rockers 1/2 turn at a time...I would do all this with the qt bottle of Marvel Mystery oil in the engine or trans fluid. This works. Its not a short cut and it fixes nothing, but it cleans the engine as well as anything so that any sludge will not be an issue.
Suckin' gas, haulin' ass.
Joined: Apr 2010
Posts: 1,100
Likes: 8
From: Newport News Virginia
First, figure out WHY there is no oil pressure on the gauge. Test oil pressure with a mechanical gauge. There is NO POINT in doing ANYTHING until you know that there is sufficient oil pressure to pump up the lifters, as they are hydraulic, and to lubricate the top end and distribute oil thru the rockers.
Also, make sure you check your geometry. You said you replaced the heads. Your pushrod length may be off. Make sure that the rocker sweep across the valve tip is in the middle and not off to one side. If it's toward the intake or exhaust, you need to get an adjustable pushrod length checker and find the correct length pushrod to use.
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Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Many year ago I experienced the same thing you are having with a 350 in my truck. First question....are you using the GM pressed rocker arms? My guess is yes. Even if you keep them in the correct order and use the same rod you will sometimes get a miss alignment between the rod and the rocker arm. Replace the arm and the rod and you should be fine. Better yet....get new rods....they are cheap and buy a set of roller rockers. You will be much happier.
If you do a search on member JoeC...you will find a couple of years ago he wrote up a good way of setting the lash using a feeler gauge. This works much better (in my opinion) than twisting the rod. Been twisting rods for 40 + years and I find this method very positive for valve adjustment. If you can't find the post, send me a PM with your email address and I will forward you the write up.
If you do a search on member JoeC...you will find a couple of years ago he wrote up a good way of setting the lash using a feeler gauge. This works much better (in my opinion) than twisting the rod. Been twisting rods for 40 + years and I find this method very positive for valve adjustment. If you can't find the post, send me a PM with your email address and I will forward you the write up.
Thread Starter
Advanced
Joined: Feb 2011
Posts: 75
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From: charleston sc
I will check the oil pressure tonight after work, drink a beer, replace some oil to clean out as mentioned, drink a beer, recheck the lash, drink another beer.. and in the morning i shall report!
Pushrod replacement is definitely in order... i just hate to take the mess that is the intake off again to get at the lifters..
You gentlemen are invaluable, I dont care what your wives say..
Pushrod replacement is definitely in order... i just hate to take the mess that is the intake off again to get at the lifters..
You gentlemen are invaluable, I dont care what your wives say..
Melting Slicks
Joined: Feb 2009
Posts: 2,072
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From: Oklahoma City OK
St. Jude '10
If you do a search on member JoeC...you will find a couple of years ago he wrote up a good way of setting the lash using a feeler gauge. This works much better (in my opinion) than twisting the rod. Been twisting rods for 40 + years and I find this method very positive for valve adjustment. If you can't find the post, send me a PM with your email address and I will forward you the write up.
. It sounds funny but basically true. It felt like the resistance would change from rocker to rocker. I finally used a very thin feeler gauge between the rocker and the valve stem and I felt it was way more accurate. I just gently move the feeler gauge in a back and forth motion until it got in a bind. Then I would loosen it a quarter turn and then back into it. Once I had them all set I went back and tightened them all 1/2 to 3/4 turn.
Thread Starter
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Joined: Feb 2011
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From: charleston sc
Ok guys, heres the lowdown..
First i changed the oil, filter, and added a detergent to the oil. Next i changed out the Oil Sending Unit and did get a good pressure reading. Finally i adusted the lash, while running... and viola, oil at each lifter was allowing flow like a young mans prostate :Y
I will add that the lifters will not pee properly if the rocker arm has been tightened down too far! As i backed off some of the leaner ones, they began to pour like the rest! Also, the ones i had tightened approximately a full turn were in fact straining the motor. It runs sooo much easier and smoother now.
Thanks CF!
First i changed the oil, filter, and added a detergent to the oil. Next i changed out the Oil Sending Unit and did get a good pressure reading. Finally i adusted the lash, while running... and viola, oil at each lifter was allowing flow like a young mans prostate :Y
I will add that the lifters will not pee properly if the rocker arm has been tightened down too far! As i backed off some of the leaner ones, they began to pour like the rest! Also, the ones i had tightened approximately a full turn were in fact straining the motor. It runs sooo much easier and smoother now.
Thanks CF!
Burning Brakes
Joined: Mar 2009
Posts: 830
Likes: 6
If you want to throw a additive in just to make sure things are clean the best is a product called Marvel Mystery Oil. Put in the car, drive it 50 miles, change your oil and put some more in and leave. The stuff is great.
