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Author Topic:   zero lash?
casper31642
Member
posted March 09, 2004 08:06 PM
what exacly does zero lash mean on lifters?


casper31642
Member
posted March 09, 2004 08:10 PM
having trouble adjusting lifters


ARR
Member
posted March 09, 2004 08:19 PM
Zero lash on Hyd lifters? If so you adjust the rockers till there is no slack in the pushrod & then go 3/4 to a full turn more. That is if the lifters are pumped up. It is alittle more tricky if they are not. If you have access to a Chilton or a Haynes manual they will tell you step by step & the sequence to adjust them in.


Okie11m
Member
posted March 09, 2004 08:26 PM
You beat me arr. But we were on the same page!!


RangeRover
Member
posted March 10, 2004 05:36 AM
The point at which there is no clearance left between the lifter and pushrod and rocker arm etc, is 0 lash. any turns past this 1/2, 3/4, etc is preload on the lifter.

Setting them at '0' LASH with no preload on the plunger will keep them from pumping up and holding a valve open when running at high rpms. But can be risky with standard hyd lifers because of the little wire clip that holds the internals inside the lifter together. The anti pump up lifters have a heavier clip more like a solid lifter circlip and can be run at 0-.002 lash. You have to keep an eye on lash though just like a solid lifter because without the preload the lifter cannot self adjust and take up any additional slack that may come due to wearing in etc.

casper31642
Member
posted March 10, 2004 09:55 AM
that might be the prob...they are not pumped up...any help here?


dirtbuster
Member
posted March 10, 2004 10:27 AM
They dont have to be pumped up. Also '0' lash means at the point where there is no clearance and you can feel slight reistnace spinning the pushrod between your fingers, not when you cant turn them anymore. If you have gone that far you have bottomed the plunger and started to open the valve. If you do it with the intake off its easier to see. Turn the nut down and when you feel slight resistance watch the pushrod cup in the lifter. At zero lash the cup will just rotate but you have not moved the plunger. Turn the nut a little father and you can see the plunger move. To truly set them at zero you would tighten them to thepoint of just seeing the cup rotate and stopping. If you were setting them like a street car then you would go 1/2-1 turn more from this point which will move the plunger down into the lifter.

Also make sure you adjust them at the right point on the cam. When the exhaust valve is fully open adjust the intake. When the intake opens then just closes adjust the exhaust. Do this on ea cylinder and you are done.

Okie11m
Member
posted March 10, 2004 09:22 PM
You can do it without them pumped up.It is just alot easier with them pumped up. I mechanic for a living and once in a while I have to re-adjust a couple if they aren't already pumped.


racerman707
Member
posted March 11, 2004 06:57 AM
Turn the motor and get the lobe down then turn the adjuster slowly till there is slight resistance on the pushrod.Then turn 1/2 to 3/4 turn to preload.Zero lash is the point where the pushrod cannot be moved up and down on the lifter and rocker,preload is the additional turn.By the way DO NOT let the motor run and turn the adjuster till it stops clicking!LOBE KILLER!!!!!!!!!1


ARR
Member
posted March 15, 2004 04:28 PM
This is something I just tried out and my engine never run better. I installed my old dist. primer and run it while adjusting the valves preventing the plungers to collapse in the lifter. I knew exactly where 0 lash was on all of them. It worked great


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