Setting lash on mechical lifters
Thread Starter
Safety Car
Joined: Apr 2001
Posts: 4,795
Likes: 1
From: Regina Saskatchewan, Canada.
Setting lash on mechical lifters
This is kind of new to me so I will tell you how I am going to do it and then you can tell me what I am doing wrong. Here goes.
I think the cam calls for 18 and 22 thou on intake and exhaust. I'll get the proper feeler under the tip of the rocker arm and valve and run the rocker arm nut down until the pushrod stops spinning in my finger tips. Then i'll install the girdles and lock 'em down. Of course, i'll be at the base of the cam so the valves are closed.
So, did I screw up?
I think the cam calls for 18 and 22 thou on intake and exhaust. I'll get the proper feeler under the tip of the rocker arm and valve and run the rocker arm nut down until the pushrod stops spinning in my finger tips. Then i'll install the girdles and lock 'em down. Of course, i'll be at the base of the cam so the valves are closed.
So, did I screw up?
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Re: Setting lash on mechical lifters (Stingy74)
I'm no expert but that is exactly how I did it when I had solid lifters and the engine ran for years with no problem till I removed it and sold it. Mine were set at 30 intake and 30 exhaust if memory serves me correctly. Was a long time ago in the seventies and have hydraulics now.
Good luck,
Good luck,
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Re: Setting lash on mechical lifters (Stingy74)
The way I do it is so that the feeler gauge has some drag as you pull it out. I don't spin the pushrods at all. When I fell a drag it is set. I tighten it back down and try the feeler gauge again. If there is still a drag I'm OK and move to the next. Somtimes after tightening it will move and I will have to go back and redo that valve. Your procedure sounds pretty good.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Re: Setting lash on mechical lifters (Stingy74)
Save yourself some grief and buy the correct tools. It's a 12 point box end with a T handle allen all in one. So you can be sinching it down while checking the feeler guage.
I do mine pretty warm. Only loosen the girdle to work on one cylinder at a time. Only loosen the girdle enough to move the rocker nut. Any extra and you get delfection which make your lash change once you tighten everything down. When you running solids, roller or mech, push down on the push rod side of the rocker when checking with the feeler guage.
You can change how the motor runs to a certian extent by lash changes. Never go above the high .020's or less than .012. I always go back and do a bump over check on each one before I button the cover up.
I do mine pretty warm. Only loosen the girdle to work on one cylinder at a time. Only loosen the girdle enough to move the rocker nut. Any extra and you get delfection which make your lash change once you tighten everything down. When you running solids, roller or mech, push down on the push rod side of the rocker when checking with the feeler guage.
You can change how the motor runs to a certian extent by lash changes. Never go above the high .020's or less than .012. I always go back and do a bump over check on each one before I button the cover up.
Drifting
Joined: Sep 1999
Posts: 1,411
Likes: 1
From: Wylie TX
Re: Setting lash on mechical lifters (gkull)
So, how do you turn the motor over when adjusting the valves? Since the headers will still be hot, I can't pull the plugs. My plan is to go buy a remote starter and disconnect the coil and bump the engine around.
I've always had hyd lifter and made the adjustments with the engine running, so this is new to me.
I've always had hyd lifter and made the adjustments with the engine running, so this is new to me.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Re: Setting lash on mechical lifters (Chris A)
I adjust mine after a drive. I let it all cool to the point where it's hot, but I won't get burnt. I just leave the window down and bump the starter. After you do it for years you don't even look at the damper degrees. No mater where the motor is you can do about 25 % of the rockers. I just draw out each bank on a piece of paper and cross out each circle as I check or set them. Every rocker is loose for 420+ degrees of crank rotation so you don't have to be right on some single degree mark.
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