Information on tappet adjuster tool

[Trevor_B]

Hi,
My dad gave me this tool the other day and told me it was for correct adjustment of grey motor tappets - only problem is that "old timers" has set in and he can't remember how to use it. Anybody have any ideas or perhasp some instructions.
Thanks,
Trevor_B

[nicko]

what an absolute jem you have there,not positive but id say the numbers are in thousands of an inch screwdriver end fits top of valve adjuster and when knob is turned the pointer shows how many thou you have opened gap from zero clearance..

[Martin]

What a fascinating looking tool - I want one to play with!!!

I haven't seen one before.  It looks as though the top "cap" might be spring loaded and will turn the slotted screw-driver head.  If it is, then here's my guess on how it might work:

I reckon a socket to fit the tappet adjuster locking nut (can't remember the size - is it 9/16?) fits over the screw-driver head and clicks into, and is held in place by, the spring tab on the front.

Close up the tappet gap to zero, then insert the slotted driver into the adjuster with the arrow on the guage set at zero.  Rotate the arm to loosen the lock-nut, wind the knob to 8 thou or 12 thou, rotate the arm to lock the lock nut.  This will be done with the engine running, hence the spring loading in the knob, so it can be held in place.

If you want to sell it, I'm a buyer, but frankly, Trev, if you're into Holden "Grey" motors and/or memorabilia, you'd be mad to sell it.  

Martin