Author Topic: Valve Adjustment Advice Needed  (Read 754 times)

0 Members and 1 Guest are viewing this topic.

Diogenes

  • Sr. Member
  • ****
  • Posts: 298
    • View Profile
Valve Adjustment Advice Needed
« on: September 26, 2025, 09:06:19 PM »
I recently obtained new adjusters for my OEM adjustable rocker assemblies (with hydraulic flat tappet cam).

I removed both assemblies, cleaned and checked everything out to make certain all was good, and then replaced all the interference fit adjusters with new adjusters purchased from DSC. My problem is, how do I begin setting the lash when I have no point of reference (other than TDC as a starting point). I guess I should have considered this more carefully before removing it all, but here I am, wondering how to best proceed.

Thanks in advance....
WHEN CRIMINALS MAKE THE LAWS, OBEYING THE LAW IS A CRIME.

1966 Galaxie 500 390 Toploader 3.89 Traction-Lock 9in.
1985 Toyota Celica Supra
1971 Montego MX wagon 351C Toploader Detroit Locker Cyclone competition gauge/dash bucket seats/console
1989 Texas DPS Police Mustang
1971 Torino GT 351C 4V AT
1968 Cougar 351W Toploader Traction-Lock 8in.
1989 Dodge Omni modified 2.5 turbo from hell

bsprowl

  • Sr. Member
  • ****
  • Posts: 297
    • View Profile
    • Ford FE Information
Re: Valve Adjustment Advice Needed
« Reply #1 on: September 26, 2025, 09:34:59 PM »
http://fordfe.info/ValveAdjustment.htm

There is an easy way and the official, book way.   Forget the official way.

With the engine hot, remove the valve cover.   Using a remote starter switch bump, the engine over until the Intake valve for cylinder No. 1 is just starting to close (is coming up).   Adjust the No. 1 Exhaust valve.

Then bump the engine around until the Exhaust valve is staring to open (going down).   Adjust the Intake valve.

If you are slow at this or your battery is weak, drop the valve cover on and run the engine for a minute or two, to warm the engine and recharge the battery.   Repeat the above steps for each cylinder.

This works because if the intake valve is closing, the exhaust valve has been closed for about a half stroke or 180 degrees of crank rotation and won't begin to open for 360 degrees of crank rotation, and when the exhaust valve is opening the intake valve has been closed for sometime (360 degrees of crank rotation) and won't begin to open for 180 degrees of crank rotation.

Diogenes

  • Sr. Member
  • ****
  • Posts: 298
    • View Profile
Re: Valve Adjustment Advice Needed
« Reply #2 on: September 26, 2025, 09:50:13 PM »
I can't run the engine until I get some sort of baseline to set the adjusters to.

All new adjusters were installed with the rocker assemblies removed from the engine, so now all the valves are closed, and I have no easy way of knowing which valves should be open, closed, opening, or closing. I should've considered this issue before removing it, but....
WHEN CRIMINALS MAKE THE LAWS, OBEYING THE LAW IS A CRIME.

1966 Galaxie 500 390 Toploader 3.89 Traction-Lock 9in.
1985 Toyota Celica Supra
1971 Montego MX wagon 351C Toploader Detroit Locker Cyclone competition gauge/dash bucket seats/console
1989 Texas DPS Police Mustang
1971 Torino GT 351C 4V AT
1968 Cougar 351W Toploader Traction-Lock 8in.
1989 Dodge Omni modified 2.5 turbo from hell

427Fastback

  • Hero Member
  • *****
  • Posts: 623
    • View Profile
Re: Valve Adjustment Advice Needed
« Reply #3 on: September 27, 2025, 02:01:33 AM »
I have a very simple way and have done it for decades.. Put the engine a TDC. I  tighten all the adjusters to zero (spin the push rod and feel it). Turn the engine over by hand aprox a 1/4 turn and set adjusters to zero.I run my fingers across the rockers. I continue doing this for a two full rotations until I am back at TDC. I now crank the adjusters down for the correct preload..I use this method on all hyd. Solids is different...I have never had to reset a hyd lifter..
1968 Mustang Fastback...427 MR 5spd (owned since 1977)
1967 Mustang coupe...Trans Am replica
1936 Diamond T 212BD
1990 Grizzly pick-up

cleandan

  • Sr. Member
  • ****
  • Posts: 487
    • View Profile
Re: Valve Adjustment Advice Needed
« Reply #4 on: October 02, 2025, 08:26:20 AM »
Rotate the camshaft so the lifter is on the base circle of the cam lobe for that valve.
I like using the EOIC method (Exhaust Opening, Intake Closing)
Gently wiggle the pushrod up and down as you tighten the adjuster (rotating can produce false results because you can't feel the ever so slight compression of the lifter plunger all the time)
Once you have removed all lash while wiggling the pushrod up and down you now are set at zero lash.
Finish by tightening to your desired preload setting (usually between 1/4 to 3/4 turn)