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'99 5.7 rocker arm torque? or adjust?


VividVisions
12-08-2009, 03:28 PM
i havn't been able to find anywhere about a torque spec or adjustment for the valves on this '99 5.7. any help would be appreciated

777stickman
12-08-2009, 05:00 PM
http://www.classiccarauto.com/impala/how_to/adjust_valves.shtml

j cAT
12-08-2009, 05:31 PM
i havn't been able to find anywhere about a torque spec or adjustment for the valves on this '99 5.7. any help would be appreciated

I don't know about the 5.7L 1999 engine but the 4.3,5.3,4.8,and the 6.o do not have any valve adjustments..

the rocker arms are torqued to 22ft lbs...on all these engines

with the engine at top dead center tighten exhaust rockers 1,2,7 and 8
tighten intake rockers 1,3,4 and 5.

then rotate the crankshaft 360 deg.

tighten exhaust rockers 3,4,5, and 6.

then intake rockers 2,6,7, and 8..


if you removed the lifters and other componets here they must all be returned to there original location..failing to do this will usually result in cam damage...

if you have lifter noise[s] it may be the cam is bad ...if your lucky the lifter/dirty..leaking...

no way to adjust out this..

VividVisions
12-08-2009, 06:36 PM
i am doing head gaskets on this burban, and i always use autozone.com for torque specs but they have nothing on these valves, and i have read different opinions on the torque or adjustments, but i havn't found one with a '99 5.7 appreciate ur help

2000CAYukon
12-08-2009, 07:05 PM
I use this method and have had very good results: http://www.chevyhiperformance.com/techarticles/148_0303_setting_valves_info/index.html

//2000CAYukon

j cAT
12-08-2009, 07:40 PM
i am doing head gaskets on this burban, and i always use autozone.com for torque specs but they have nothing on these valves, and i have read different opinions on the torque or adjustments, but i havn't found one with a '99 5.7 appreciate ur help

I was thinking of this for a time and I do have this..there is an adjustment for the 5.7L engine..

with the engine in the #1 FIRING POSITION valves exhaust 1,3,4,8 and intake 1,2,5,7 can be adjusted, back off rocker arm nut until lash is felt in valve push rod .then tighten valve rocker arm nut until all lash is removed..zero lash can be felt by moving valve pushrod up and down until no movement. when these are all done like this rotate the rocker arm nut one more 360 deg rotation in the tighten direction.

now rotate the crankshaft one revolution 360 deg.this is the #6 firing position now you can adjust the exhaust 2,5,6,7 and the intake 3,4,6,8... the same way thats it..
good luck..

VividVisions
12-09-2009, 01:37 PM
ok when i get zero lash, then tighten 360 or even 180 degrees i am not getting any compression out of the cylinder, started out with number 1 intake and exaust, both valves are closed, i adjust it, go back counter clockwise the back to clockwise to check it but im getting no pressure at the spark plug hole, zero lash does just fine tho

777stickman
12-09-2009, 05:22 PM
Well if I had to make a guess it's that you're adjusting #1 valves with the cam in the #6 firing position. Keep in mind the crank rotates twice to the cams once. This is a very common error.

The links that 2000CAYukon and I both suggested have the same procedure for adjusting the valve train. Even though they speak about classic small blocks this procedure will work for your 5.7. This would eliminate any errors as to #1 TDC or #6 TDC.

One tip is to remove all spark plugs. Take your time and I'm sure it will work out for the best.

VividVisions
12-09-2009, 05:54 PM
i can physically see the valve starting to open right after zero lash, as soon as i go past that too do the 3/4 turn the valve opens

j cAT
12-09-2009, 06:11 PM
i can physically see the valve starting to open right after zero lash, as soon as i go past that too do the 3/4 turn the valve opens

are you sure you are adjusting the correct valve intake / exhaust ????
could have this reversed as well..

VividVisions
12-09-2009, 07:03 PM
both lifters are down in the block, not sticking up when they open the valve

777stickman
12-09-2009, 07:10 PM
The zero lash thing has to be done very slowly!! It is possible to go beyond zero lash and still be able to spin the push rod. It's also possible the push rods are not seated properly in the lifter.

One thing I always check after a full valve adjustment is that all rocker arm studs show the same amount of threads above the adjusting nuts. On stock heads I'm thinking around 5-6 threads showing above the nuts.

Maybe you need to get with a buddy who's done this before and see if he can work with you to get it figured out.

VividVisions
12-09-2009, 08:16 PM
well i'm gonna start it up at zero lash, see what happens, i've checked double checked to see if they are seated right, all my buddies that i have called keep saying they thought with hyd lifter u just torque em. i'll keep ya posted after i find my tools that i threw across the garage

j cAT
12-10-2009, 07:38 AM
well i'm gonna start it up at zero lash, see what happens, i've checked double checked to see if they are seated right, all my buddies that i have called keep saying they thought with hyd lifter u just torque em.

with hyd lifters you must preload ...this is what the extra 360 deg nut tightening is all about..that way the lifter is in the mid range of adjustment..of lifter capacity..

iroc343
12-12-2009, 05:34 AM
You must adjust the rocker arm when the lifter is on the base circle (lowest point) on the cam. The easiest way I have found, is to do each cylinder separately and remember; do the intake just as the exhaust starts to open and do the exhaust as the intake is almost closed. Spin the pushrod until it stops when it reaches zero clearance, then go your additional turns. I have always used 1/4 turn for performance applications and 1/2 turn for all others. I know they say 1 full turn, but I have always had difficulty getting the engine to want to run smoothly at that setting, just my experience. Hope this helps.

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