Hydraulic Lifter Adjustment - preload

[Anonymous]

I am concerned that I may have too much preload on my lifters. Recently went to 1.6 adjustable rockers. Adjusted the valves COLD. Adjusted the preload until I could not turn the push rod by hand. Tightened the adjusting screw 1/4 turn and locked it down. Set all of the valves and went through the rotation again. Several of the push rod could be turned by hand on the second, and even the third pass. Each time I re-adjusted with the same process. Took about 5 passes before all of the setting were stable, i.e., did not losen up. Could this process have collapsed the lifters. I assume if this is the case I could ultimately burn valves. What do you think? What would be the best way to start over, i.e., pump up the lifters and re-adjust.

Thanks - Steve

 

[mjpchief]

Should go this process only once. If you go back later you will find your lifters have bled off a little and will allow the push rods to turn easily. Make sure your lifters are pumped up and adjust the way you did and stop with one adjustment. Should do it.

 

[Anonymous]

Given that I don't know to what extent I have collapsed the lifters I would rather not start the engine to pump them up. What do you think about pulling the plugs, backing off the adjusters a turn of two, and cranking the engine over with the starter?

Steve

 

[addo]

1. Pulling the plugs is a given. Why waste energy turning against compression pressure?

2. Once you slacken the lifters all off to the point of slop, they'll slowly spring up if collapsed.

3. With the TDC / compression / No.1 method (probably like your manual), spin the pushrod while tightening. From the point you feel the slightest drag, go 1/2 to 1 turn on the adjuster, proceed through the rest of the crank cycle for other cylinders...

4. Use a length of tube to listen for looseness in each adjuster, as it runs. 1/4 turn more is usually plenty.

Steve, I think the car would just run really roughly. You'd notice and fix it before any damage occurred. Hydraulics are pretty docile. You could probably even slack them off while running, listening to the idle improve.

Cheers, Adam.

 

[mjpchief]

I use an old distributor and make an oil pump drive so I can pump up oil pressure with a hand drill. That way you don't have to spin the motor and worry about hitting piston with a valve. I would back all rockers off and start from scratch to avoid any problems. You will have to remove the gear from the old distributor so you can spin the shaft with the drill.

 

[Anonymous]

Hey mjpchief and addo,

Thank you very much. I feel much better about this now.

Steve

 

[Anonymous]

Hey mjpchief and addo,

Thank you very much. I feel much better about this now.

Steve