Too much lifter adjustment? Oops...
Thread Starter
Burning Brakes
Joined: Dec 2002
Posts: 1,069
Likes: 2
From: Sherwood Park AB
Too much lifter adjustment? Oops...
What happens when you adjust your hydraulic lifters too tight? I installed new cam (XE268) and hydraulic lifters.
I read to adjust them anywhere from 1/4 to 1/2 past zero lash. The problem is I thought zero lash meant that you could not turn the push rods; instead of just being able to move them up and down. I tried to start the engine and the lifters were noisy while cranking, then it backfired. Now I am trying to troubleshoot a no spark issue.
Ahhh, another learning experience.
I read to adjust them anywhere from 1/4 to 1/2 past zero lash. The problem is I thought zero lash meant that you could not turn the push rods; instead of just being able to move them up and down. I tried to start the engine and the lifters were noisy while cranking, then it backfired. Now I am trying to troubleshoot a no spark issue.
Ahhh, another learning experience.
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Originally Posted by rexx78
What happens when you adjust your hydraulic lifters too tight? I installed new cam (XE268) and hydraulic lifters.
I read to adjust them anywhere from 1/4 to 1/2 past zero lash. The problem is I thought zero lash meant that you could not turn the push rods; instead of just being able to move them up and down. I tried to start the engine and the lifters were noisy while cranking, then it backfired. Now I am trying to troubleshoot a no spark issue.
Ahhh, another learning experience.
I read to adjust them anywhere from 1/4 to 1/2 past zero lash. The problem is I thought zero lash meant that you could not turn the push rods; instead of just being able to move them up and down. I tried to start the engine and the lifters were noisy while cranking, then it backfired. Now I am trying to troubleshoot a no spark issue.
Ahhh, another learning experience.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by rexx78
What happens when you adjust your hydraulic lifters too tight? I installed new cam (XE268) and hydraulic lifters.
I read to adjust them anywhere from 1/4 to 1/2 past zero lash. The problem is I thought zero lash meant that you could not turn the push rods; instead of just being able to move them up and down. I tried to start the engine and the lifters were noisy while cranking, then it backfired. Now I am trying to troubleshoot a no spark issue.
Ahhh, another learning experience.
I read to adjust them anywhere from 1/4 to 1/2 past zero lash. The problem is I thought zero lash meant that you could not turn the push rods; instead of just being able to move them up and down. I tried to start the engine and the lifters were noisy while cranking, then it backfired. Now I am trying to troubleshoot a no spark issue.
Ahhh, another learning experience.
I understand the frustration. It's hard to tell when finger tight is as tight as someone else's fingers. Mine would be a light tighter than someone else, so I may have over adjusted lash. Back them all off 1/4 turn, and see if things improve. Sounds like you did everything right except a hair too far...if that's the problem.
How sure are you of the timing?
Le Mans Master
Joined: Oct 2001
Posts: 5,943
Likes: 3
From: Wildwood IL
Originally Posted by rexx78
What happens when you adjust your hydraulic lifters too tight? I installed new cam (XE268) and hydraulic lifters.
.
.
Eddie
Race Director
Joined: Sep 2004
Posts: 11,874
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
read Lars article on adjusting them....also try using a feeler gauge and as you start to tighten them try using the thinest feeler gauge moving it in and out and when it starts to bite you have basically hit zero lash......go 1/2 way past that and you are good to go... did you use new lifters? and did you prime the engine with oil first?
you need to get a new cam running ASAP and break it in or you will wipe a lobe.
you need to get a new cam running ASAP and break it in or you will wipe a lobe.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I've read Lar's paper, and had my own method for previous motors...but I wonder how that guide for valve lash works with roller hyd. lifters. I have never adjusted those kind before and I don't want to assume anything.
Is it the same process?
Is it the same process?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
[QUOTE=hayman][QUOTE=bobs77vet]read Lars article on adjusting them....
Where do you find this article at?
Bill
Here's a link to it on BarryK's site.
It's a little slow to load. Then, just save it to your computer.
http://69.253.166.197/corvettes/vett...ch%20paper.pdf
Where do you find this article at?
Bill
Here's a link to it on BarryK's site.
It's a little slow to load. Then, just save it to your computer.
http://69.253.166.197/corvettes/vett...ch%20paper.pdf
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Race Director
Joined: Sep 2001
Posts: 10,560
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From: Wellington, FL
St. Jude Donor '11 thru '25
Another simplier way to adjust hydraulic lifters is to use a .0015 feeler between the rocker and the valve stem. This eliminates the fooling around with the push rod for adj. I've used this method and it works. Hope this helps.
Thread Starter
Burning Brakes
Joined: Dec 2002
Posts: 1,069
Likes: 2
From: Sherwood Park AB
Thanks for the replies
If the rockers are too tight, then the valves open at the wrong time, either early or late, correct? Could this have caused the backfire?
Jud
What do you mean "the involved cylinder will not fire" is this a valve lift timing issue, or could it have something to do with my no spark? I like the feeler gauge method.
Durango
I backed them all off 1/4 of a turn, after I read another paper where I realized my "zero lash" was wrong.
EZred/Bob
I used lots of cam lube and primed the engine with an oiler throught the dist hole. I have cranked it over quite a bit after replacing piece by piece of my HEI system. I hope I didn't wipe a lobe. I guess I will have to pull the cam and look.
I have only had the engine out twice since the last time it ran... My level of frustration is rising.
My wife (Ford Chick) keeps bugging me that her Mustang runs just fine.
Jud
What do you mean "the involved cylinder will not fire" is this a valve lift timing issue, or could it have something to do with my no spark? I like the feeler gauge method.
Durango
I backed them all off 1/4 of a turn, after I read another paper where I realized my "zero lash" was wrong.
EZred/Bob
I used lots of cam lube and primed the engine with an oiler throught the dist hole. I have cranked it over quite a bit after replacing piece by piece of my HEI system. I hope I didn't wipe a lobe. I guess I will have to pull the cam and look.
I have only had the engine out twice since the last time it ran... My level of frustration is rising.
My wife (Ford Chick) keeps bugging me that her Mustang runs just fine.
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Jud
What do you mean "the involved cylinder will not fire" is this a valve lift timing issue, or could it have something to do with my no spark? I like the feeler gauge method.
What I'm saying is when a lifter is getting too tightly adjusted, that particular cylinder will begin to miss. As far as the feeler guage method, I got that out of a Vette Haynes manual when I was going thru what you are now experiencing. Then I tried this method, and it was really a piece of cake.
BTW, do not give up. You will get it. And when you do, you'll be sky high!
What do you mean "the involved cylinder will not fire" is this a valve lift timing issue, or could it have something to do with my no spark? I like the feeler gauge method.
What I'm saying is when a lifter is getting too tightly adjusted, that particular cylinder will begin to miss. As far as the feeler guage method, I got that out of a Vette Haynes manual when I was going thru what you are now experiencing. Then I tried this method, and it was really a piece of cake.
BTW, do not give up. You will get it. And when you do, you'll be sky high!
Last edited by Jud Chapin; Nov 7, 2006 at 03:58 PM.
Race Director
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From: Wellington, FL
St. Jude Donor '11 thru '25
BTW, Mark, I assume you are adjusting the valves in the proper sequence. That is certain valves are adjusted when the #1 cylinder is at top dead center, and others when #6 is at top dead center. I just want to make sure that's what you are doing. 
Le Mans Master
Joined: Oct 2005
Posts: 9,429
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From: Macon, GA
Did you adjust it down to where there is pushrod resistance (zero lash) and then turn it down 1/2 to 3/4 turn? Well, if you did this, you more than likely have the valves not closing all the way.
Hydraulic lifters require roughly a .030" pintle depth setting. This means that you adjust valves by the depth that the pintle in the lifter drops. Too tight and the valves do not close, too loose and they rattle and do not open properly and damage the lifter.
Sounds to me like the adjustment was done out of sequence, or a few a re still not adjusted correctly.
I'm sure you know what you are doing, but did you do it this way adjusting off the backside of the lobe (or base circle)?
Intake valve adjustment:
with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve
Exhaust valve adjsutment.
with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve
Hydraulic lifters require roughly a .030" pintle depth setting. This means that you adjust valves by the depth that the pintle in the lifter drops. Too tight and the valves do not close, too loose and they rattle and do not open properly and damage the lifter.
Sounds to me like the adjustment was done out of sequence, or a few a re still not adjusted correctly.
I'm sure you know what you are doing, but did you do it this way adjusting off the backside of the lobe (or base circle)?
Intake valve adjustment:
with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve
Exhaust valve adjsutment.
with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve
Instructor
Joined: Sep 2006
Posts: 192
Likes: 0
From: Fort Lauderdale FL
Originally Posted by sperkins
Did you adjust it down to where there is pushrod resistance (zero lash) and then turn it down 1/2 to 3/4 turn? Well, if you did this, you more than likely have the valves not closing all the way.
Hydraulic lifters require roughly a .030" pintle depth setting. This means that you adjust valves by the depth that the pintle in the lifter drops. Too tight and the valves do not close, too loose and they rattle and do not open properly and damage the lifter.
Sounds to me like the adjustment was done out of sequence, or a few a re still not adjusted correctly.
I'm sure you know what you are doing, but did you do it this way adjusting off the backside of the lobe (or base circle)?
Intake valve adjustment:
with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve
Exhaust valve adjsutment.
with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve
Hydraulic lifters require roughly a .030" pintle depth setting. This means that you adjust valves by the depth that the pintle in the lifter drops. Too tight and the valves do not close, too loose and they rattle and do not open properly and damage the lifter.
Sounds to me like the adjustment was done out of sequence, or a few a re still not adjusted correctly.
I'm sure you know what you are doing, but did you do it this way adjusting off the backside of the lobe (or base circle)?
Intake valve adjustment:
with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve
Exhaust valve adjsutment.
with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve
The valves too tight will force them open, how open depends on how overtight they are, you will experience a lowered compression to none whatsoever in that cylinder, so performance will drop.One of the best methods to adjust valve lash that I have seen and use is to adjust them for maximum compression with a compression gauge. Screw in the gauge, adjust both intake and exhaust, move on to the next and repeat over and over then do a final test on all cylinders, try to get them all within 5psi of each other.
This method has two distinct advantages, first is you will know and balance the compression of each cylinder, this should generate the most power, secondly, if compression cannot be balanced in one or two cylinders, then you know you have deeper issues.
Just remember as with any compression test, test it at operating temp.
Just my $0.02
Last edited by 75coupered; Nov 7, 2006 at 07:27 PM.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by 75coupered
This method has two distinct advantages, first is you will know and balance the compression of each cylinder, this should generate the most power, secondly, if compression cannot be balanced in one or two cylinders, then you know you have deeper issues.
Just remember as with any compression test, test it at operating temp.
Just my $0.02
Just remember as with any compression test, test it at operating temp.
Just my $0.02
So the above is not something that can be done only when the engine is running.
Instructor
Joined: Sep 2006
Posts: 192
Likes: 0
From: Fort Lauderdale FL
Originally Posted by Durango_boy
So the above is not something that can be done only when the engine is running.
Take the next clyinder and do the same process, at some point you will find that you can balance all cyclinders to within 5psi of each other by adjusting each cylinder. If you do this you set up each valve to work appropriately in harmony with the others you should be done with the adjustment process.
There are way too many variables to compensate for to use a simple zero lash quarter turn tight method, you can still end up with a lot of variation in the cylinder compression so I prefer having an accurate readout as a reference. When I did this to my low compression 75 each cylinder came out to 155psi.
Melting Slicks
Joined: Feb 2006
Posts: 2,209
Likes: 0
From: Mo
The best way to adjust Hyd lifters is to.this is messy so just have to clean up after.I took a old valve cover and cut the middle out.
1. start engine let it warm up,(leave valve covers on for this)
2.when warm,start on #1
3.back off adjusting nut till the rockers clatter.tight just till they are quiet and leave them,you can put a 1/8 turn but nomore.tight the poly locks if running them
4.Go around engine doing all lifters the same way.
5.clean up and reinstall V/C.
the feeler gauge really only works on solid lifters,hyd really need done with the engine running.
1. start engine let it warm up,(leave valve covers on for this)
2.when warm,start on #1
3.back off adjusting nut till the rockers clatter.tight just till they are quiet and leave them,you can put a 1/8 turn but nomore.tight the poly locks if running them
4.Go around engine doing all lifters the same way.
5.clean up and reinstall V/C.
the feeler gauge really only works on solid lifters,hyd really need done with the engine running.
Racer
Joined: Apr 2005
Posts: 464
Likes: 0
From: Charleston South Carolina
Originally Posted by l88rocket
The best way to adjust Hyd lifters is to.this is messy so just have to clean up after.I took a old valve cover and cut the middle out.
1. start engine let it warm up,(leave valve covers on for this)
2.when warm,start on #1
3.back off adjusting nut till the rockers clatter.tight just till they are quiet and leave them,you can put a 1/8 turn but nomore.tight the poly locks if running them
4.Go around engine doing all lifters the same way.
5.clean up and reinstall V/C.
the feeler gauge really only works on solid lifters,hyd really need done with the engine running.
1. start engine let it warm up,(leave valve covers on for this)
2.when warm,start on #1
3.back off adjusting nut till the rockers clatter.tight just till they are quiet and leave them,you can put a 1/8 turn but nomore.tight the poly locks if running them
4.Go around engine doing all lifters the same way.
5.clean up and reinstall V/C.
the feeler gauge really only works on solid lifters,hyd really need done with the engine running.
This is the way I do it. I used the "opposing cylinder method" first and then run the engine with the cut valve cover and I loosen till clatter is there and only tighten an 1/8th after the clatter goes away. Works every time.