PDA

View Full Version : Hydrolic lifter need advise on adjustments..



obengston
09-07-2010, 10:10 AM
I currently set all my roller rockers, but the questions I have are...
1. I few of the lifters once I take them to zero lash (prior to turning another 1/4-to 1 full turn depending on who you ask) has no movement in them. Basically on some you can pump up/down with your fingers others want move at all. Is this because they are bad. On the number 2 cylinder the exhaust lifter will not move and after I take it to zero lash the turn it anymore beyond that it will hold the valve open. So what I did was just take it to zero lash finger tight and that was it.

2. After you take it to zeron lash and then turn it another lets say 1 turn, you still have a good amoutn that you can pump it down with your finger and lift it off the valve tip. What would happen if I adjusted that free play to where it only pumps down just enough to lift off the valve. Will it pupm up under heat and cause my valve to hit the piston. Now I did leave enough play to allow it to come off the valve tip a little.

What about the rockers that once you set them to zero lash the will not allow any movement while trying to pump the lifer down with your finger. I even tried to slide a screw driver on top of the valve and lift the rocker in order to have it pump down but instead it would open the valve. I just set it to zero and left them, the others I adjusted down to where after being pushed down they would lift off the valve just a little.


I know this was alot but needed to explain.

Thanks
Oscar

ArtosDracon
09-07-2010, 10:59 PM
Are you rotating the cam as you're setting the rockers to 0 lash? If not you've got some lifters compressed between the rocker and the cam lobe and some on the flat of the cam, which would keep the lifter from being compressed.

obengston
09-08-2010, 03:10 AM
Yes sorry should have mentioned. I know how to set the rockers. More curious about the lifter / lash. As mentioned above.

vette427-sbc
09-08-2010, 06:06 PM
I had a similar problem with mine... I would set valves, and when I started the car, I would get one valve that would always stay open.
Turns out I collapsed a lifter and with no oil pressure, the seat for the pushrod in the lifter would fall down a bit. When the motor started, oil pressure would build and push the seat back up, holding the valve open.

obengston
09-09-2010, 04:06 AM
I was thinking it had collapsed.