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-   -   97 5.7 ltr lifters clogged or need adjustment?? (https://www.truckforums.com/forum/chevy-silverado-gmc-sierra-forum-11/97-5-7-ltr-lifters-clogged-need-adjustment-18236/)

ninjaneer911 Jan 26, 2012 12:19 PM

97 5.7 ltr lifters clogged or need adjustment??
 
Hey guys, first post for a newbie. 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 sending unit. 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? I havent did the final adjustment while running, will the the lifters being torqued to much cause the oil flow to be very low? Im scared to let it run even to adjust them to find out.. Advice.. please...

NullHead Jan 26, 2012 12:48 PM

Well firstly, I was under the impression that the proper procedure of adjusting rocker arms was while the engine was at TDC on cyl #1. Do the adjustment, turn the crank manually to the next timing mark on the balancer, do cyl #2 and so on.

I believe there is a nice section about this in the Haynes manual. I cannot recall the specific procedures though.

ninjaneer911 Jan 26, 2012 12:55 PM

Note that i did initially adjust the rocker arms according to the manual. Everyone ive talked to says its best to fine tune while the motor is running to optimize.

ninjaneer911 Jan 26, 2012 12:57 PM

Oil flow is my concern though, why no oil to some of the rockers?

Mr_Shamrock Jan 26, 2012 01:02 PM

Yes please make sure the lifters are adjusted correctly or at least close before trying to start it. If they are too tight it can cause issues although I don't think it will affect oil pressure. Make sure the distributor gear is turning the oil pump.

ninjaneer911 Jan 26, 2012 01:31 PM

well some of the rockers are peeing oil nicely so its moving oil to the top of the motor. basically your gettin at Ive got clogged lifters?

NullHead Jan 26, 2012 03:13 PM

I don't know that you have clogged lifters, but what does the other bank of lifters do?

What cylinders are the problematic lifters on? One side of the engine, or intake on #1, exhaust on #4 etc. What lifter, for what cylinder? Is there a pattern?

ninjaneer911 Jan 31, 2012 09:29 AM

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!

NullHead Jan 31, 2012 02:20 PM

I'm glad you figured it out!


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