Valve lash adjustment - 4.3 v6

[ROKRIG]

Need input on this ASAP...

1. What do you consider zero lash in the pushrod? Just when you can't fully rotate it at all or is it when you can turn it back and forth just a little?

2. What you make of this... On the compression stroke, I adjusted the exhaust on #6 and intake on #2. After rotating the engine 1 full revolution, I noticed that the #6 valve was all loosey goosey. Should I just leave it as and let oil pressure take out the slack when I start it again or should I adjust it or do you think there's something else going on? The freshly adjusted intake valve on #2 was just fine (not all sloppy)

Any help from any of you more experienced engine guys would be greatly appreciated. I want to take my buggy to Naches this weekend but I'm hesitant since I'm not sure what the heck is going on with my valves

Terry

 

[Ed Bister]

If it's a chevy......

Get them close with out overtighining then start the motor back them off till they click then tightin them up till they just stop clicking and go a 1/2 turn past were the clicking went away.

This will get you were you need to be:awesomework:

 

[Boonie Buster]

Do you have a manual on what it says to do to adjust these?, You're gonna need to have the motor running to do a final adjustment (NOT NOW THOUGH!!!! those babies are still out of wack!)

 

[Boonie Buster]

if it's a chevy......

Get them close with out overtighining then start the motor back them off till they click then tightin them up till they just stop clicking and go a 1/2 turn past were the clicking went away.

This will get you were you need to be:awesomework:

x2 :d

 

[ROKRIG]

What do you think about my second question?

 

[Binder]

When the pushrod is just snug works fine for zero lash. IIRC on that engine you should be 1-1/4 turns past zero lash assuming hyd lifters. Look that up if you have a book....What I do to make it less confusing is just bring number one to TDC compression stroke and do both valves. Following the firing order turn the next cylinder to TDC and do that one. Repeat for each cylinder.......You may need to do a running adjustment too after all of this.

 

[Boonie Buster]

When the pushrod is just snug works fine for zero lash. IIRC on that engine you should be 1-1/4 turns past zero lash assuming hyd lifters. Look that up if you have a book....What I do to make it less confusing is just bring number one to TDC compression stroke and do both valves. Following the firing order turn the next cylinder to TDC and do that one. Repeat for each cylinder.......You WILL need to do a running adjustment too after all of this.

edited it for ya! :;

 

[Boonie Buster]

What do you think about my second question?

bring it down snug, NOT TIGHT, just snug, cycle the motor by hand. repeat.

 

[WHITE TRASH1]

Fire it up and let it idle so the lifters are pumped up with oil pressure. back one off at a time until it taps then slowly snug it back down till it is quiet then go another 1/2-3/4 turn and leave it and move on to the next.

 

[crash2]

Fire it up and let it idle so the lifters are pumped up with oil pressure. back one off at a time until it taps then slowly snug it back down till it is quiet then go another 1/2-3/4 turn and leave it and move on to the next.

You should never have to use that method--if you do then you have an issue with oiling or a bad lifter..

Follow the porcedure with zero lash and one turn after zero lash.

 

[WHITE TRASH1]

You should never have to use that method--if you do then you have an issue with oiling or a bad lifter..

Follow the porcedure with zero lash and one turn after zero lash.

Hell unless I have an engine on the stand that's how I always do it because it's easy... :redneck:

 

[ROKRIG]

Crash, how would you describe zero lash as it pertains to pushrods? You work on Chevrolet product quite a bit don't you?

Do you have any thoughts on why the #6 exhaust valve rocker arm would be loose on the second revolution after it was nice and snug on the compression stroke? One thing I read online suggested the stud might be backing out?

 

[Binder]

One thing I read online suggested the stud might be backing out?

Not when you're just turning it by hand.....To answer your question it could be that you're following the steps intended for a V8 or you may not be on the compession stroke.

 

[ROKRIG]

I'm referencing both a Chiltons and Chevrolet OEM factory manual specifically for this motor.

I'm kinda thinking I'll adjust the #6 exhaust rocker arm on the compression stroke per the instructions and even if it's loose on the second revolution when hand-cranking, I'll put everything back together and fire it up. Maybe the oil pressure will take out the slack?

I've confirmed the compression stroke by removing the #1 spark plug and hand cranking the engine until my trusty helper (wife) felt air coming out of the spark plug hole. I then turned the crank until the mark on the pulley lined up with the zero degree mark on the timing scale. Sound correct?

In addition, since for some reason I have 2 grooves on the crank pulley, I confirmed which groove corresponded with TDC by inserting a dowel into the #1 spark plug hole, measuring the amount the dowel was inserted when each of the grooves was aligned with the 0 degree mark on the timing scale. Sound good?

 

[crash2]

Crash, how would you describe zero lash as it pertains to pushrods? You work on Chevrolet product quite a bit don't you?

Do you have any thoughts on why the #6 exhaust valve rocker arm would be loose on the second revolution after it was nice and snug on the compression stroke? One thing I read online suggested the stud might be backing out?

as you tighten down the rocker--with your thumb and forfinger turn/spin the pushrod. Do this while tightening the rocker till the you can't turn it. Thats zero backlash. Then one turn past....

Also--what year motor is this?

 

[crash2]

I'm referencing both a Chiltons and Chevrolet OEM factory manual specifically for this motor.

I'm kinda thinking I'll adjust the #6 exhaust rocker arm on the compression stroke per the instructions and even if it's loose on the second revolution when hand-cranking, I'll put everything back together and fire it up. Maybe the oil pressure will take out the slack?

Lifter could be just bleeding down--not abnormal in a motor with some miles...

 

[ROKRIG]

1989 4.3 v6 (z series)

 

[CHOP SHOP]

Lifter could be just bleeding down--not abnormal in a motor with some miles...

so bench setting it would be a waste of time.

SET THEM RUNNING.

Crash you have gave some of the worst advice ever in this thread.

Setting them cold and still is a waste of time. Not my opinion, thats a FACT.

 

[crash2]

so bench setting it would be a waste of time.

SET THEM RUNNING.

Crash you have gave some of the worst advice ever in this thread.

Setting them cold and still is a waste of time. Not my opinion, thats a FACT.

really--guess the dozens I have done professionally have never been right huh

If you follow the procedure they will be fine---if you follow the procedure and you have a noise--there is a problem either with the feed or a lifter..

 

[Binder]

I've confirmed the compression stroke by removing the #1 spark plug and hand cranking the engine until my trusty helper (wife) felt air coming out of the spark plug hole. I then turned the crank until the mark on the pulley lined up with the zero degree mark on the timing scale. Sound correct?

You still may not have the compression stroke. If the lifters are loose you will get compression on both the compression stroke AND the exhaust stroke. You either need to line up the marks on the timing chain (probably covered up) or crank the engine by hand watching the lifters. After the intake lifter goes down then continue to where the timing marks line up. Make sure to turn it the correct direction.