Adjustable Hydrolic Tappets

[out-of-this-wor]

I would like to know how you adjust these tappets, accoprding to the manual, you depress tappet with a special tool, which i am having difficulty in getting. Is there any other way of adjusting them ?
It is a 289 mustang..

 

[SoCalCruising]

Assuming the motor is assembled ... and has adjustable rockers ....
Find #1 cylinder on distributor cap. Mark it, or remember it, and remove distributor cap. Set pointer to TDC compression stroke. The rotor will be pointing at #1 spark plug wire position on distributor when in TDC compression stroke.

Remove valve covers. You may now adjust both tappets for #1 cylinder. To adjust, back off nuts from rockers/studs of both intake and exhaust until pushrod rotates freely (no resistance). Now, using finger pressure only, tighten nuts until you can just feel them engage pushrods - you can now feel some resistance if you try to rotate pushrod. This is "zero lash" - the point where the rocker is just being lightly pressed against valve tip. Now, tighten nut 1/2 - 3/4 turn and lock it down.

Using breaker bar and socket on damper bolt, rotate engine 90 degrees (same direction it normall rotates when running). Move to #5 cylinder and repeat process. When finished with #5, rotate 90 degrees for next cylinder, repeat. Keep on going following 289 firing order: 1-5-4-2-6-3-7-8.

 

[out-of-this-wor]

hydrolic tappets

Thank you for your reply, this is referring to hydrolic adjustable tappets, not solid tappets ?
You refer in your reply about two locking nuts which this has only got one nut and according to the manual there is a feeler gauge gap required.
I am only asking as not many of these engines came with adjustable hydrolic tappets.
Is what you are referring to ?

Thanks for your time

 

[bnickel]

Thank you for your reply, this is referring to hydrolic adjustable tappets, not solid tappets ?
You refer in your reply about two locking nuts which this has only got one nut and according to the manual there is a feeler gauge gap required.
I am only asking as not many of these engines came with adjustable hydrolic tappets.
Is what you are referring to ?

Thanks for your time

first off, what engine do you have?

 

[out-of-this-wor]

tappets

This is a 1968 289, 4.7 litre.
They are definitely hydrolic adjustable tappets,i have checked that out myself, the push rods need to be compressed down according to the manual and then gapped accordingly using this special tool, this is all by the manual.
What i am trying to find out is can i adjust them without this tool ?
They are defiitely not solid lifters on this engine.

Thanks

 

[bnickel]

hmmm, that's strange. all of the 68 289s i've ver seen have non-adjustable hydraulic lifters with "rail" type rockers.

 

[D.Hearne]

68's are adjustable rail rockers. 69 was when the positive stop studs came out. To adjust the 66-68 rail rockers, you can do it with the engine running, or not. Running, you simply tighten down the nut till the engien starts to miss, then back off a tad, like about 1/2 turn. To adjust with the engine stopped, you need each cylinder in the firing order at TDC at the firing stroke (I use the distributor rotor to tell, doing one each in the order, then rotating the crank 1/4 turn for each) Tighten the nut while spinning the pushrod between two fingers, when you feel the pushrod tighten, tighten the nut another 1/2 to 3/4 turn. Do all eight in the firing order and you're done.

 

[SoCalCruising]

Yes, my procedure is for hydraulic tappets. It is consistent with D.Hearne's advice.