abrush

O.k., to make a long story short I ended up losing oil pressure due to a faulty oil pump on my 65 fastback over the weekend. Because of this I have pulled the engine as I'm sure my bearings will need replaced and crank possibly turned. I shut the car down before the engine locked up but did hear some knocking from the bottom end.

I have a comp cams XE268 cam, hydralic lifters and cylinder heads with the screw in studs and springs for this set up. Since I have the engine pulled I plan to install these parts when I reassemble. However I have found conflicting information on how to set the valve lash or adjust the roller rockers. I have watched a couple videos and one shop says to open the intake valve all the way up and as soon as it starts down stop. Then put a ratchet at the 12:00 position and turn to the 5:00 position. Stop there and find zero lash. Once found turn the poly lock one additional turn. Then go to the exhaust valve, find zero lash and turn the poly lock an additional turn too. Move on to the next cylinder.

Another video is telling me adjust the intake valve when the exhaust lifter/pushrod on the same cylinder is just starting to come up. Then adjust the exhaust valve when the intake/lifter pushrod on the same cylinder is 3/4 of the way down. They are saying to turn the poly lock a half turn.

Can someone who has done this before clairify the correct way?? I want to make sure this is done right the first time around as to avoid damaging anything. Thanks.

JMD

Assuming your lifters are hydraulic, you want to get the lifter plungers in the center of their travel. I usually use a kind of informal way of doing this that works well with NEW (no oil in them) lifters.

It is easier to show this procedure than to try to explain it....

(BTT)

TexasAxMan

First you have to find TDC on the compression stroke of the #1 cylinder, both valves should be closed. Adjust both valves on that cylinder, I spin to zero lash and then go an additional 1/2 turn. Next, rotate the engine 1/4 turn and go to the next cylinder in the firing order. Turning the engine 1/4 turn after each cylinder should keep you in the firing order, after you've done all 8 cylinders you'll be back at TDC on #1.

scottybaccus

The most important part is to ensure that the lifter is on the base circle of the cam.
Then find the zero lash point by feeling for slack by trying to rattle the pushrod up and down between the lifter and rocker-arm. Once you take out the slack, 1/4 turn of preload on the plunger.

With a Chevy, you can set several valves while on TDC for number one, rotate the crank 360* and adjust several more, 360* for another batch, then once more for the remainder. The same process will work for any engine, but I would have to research which valves at each step for a Ford.

dmaclaren

So, what do you do if you have hyd. ifters, and no poly locks on a 351? I thought with this set up, you can only tighten all the way down. Would it be better for me to change over to ploy locks? Am I doing damage to the engine with my current set up with tightened all the way down?

Starfury

How do you have no poly locks if you have roller rockers? Roller rockers require poly locks.

dmaclaren

I don't have roller, rails.

Starfury

Ah. Well, assuming your rockers are non-adjustable, it depends on if you have the proper length pushrod. Assuming you do, torqueing the rocker nuts down all the way should give you proper lifter preload.

kalli

as for the hydraulic version as the OP was asking ...
TexasAxMan mentioned to do every cylinder when it's at TDC. this is to make sure that the valve is fully closed (pushrod sitting on base of cam lobe as mentioned above).

A lot of older books will tell you to find zero and turn 3/4 or full turn from there.
I have the same cam as you and if you use the matching lifters, then this is too much for them. Too much preload. I found it a lot better to use no more than 1/4 turn with mine from zero lash.

Since I'm sometimes not sure about how much exactly I did have the engine turned, I use the approach mentioned above with the (check on the other valve).
If the intake valve is going down/closing then I know for a fact that the exhaust valve is fully closed. So usually I look at #1 cylinder intake, turn until intake is on it's way down and at this stage do the exhaust valve. Then I keep turning engine until the intake valve for the next cylinder in firing order is going down.
For the intake valve I set it when the exhaust valve is opening (not open, opening!)

once I'm done with all of that I do it once more with the engine running (just to be sure). For this I have old valvecovers to not make a mess that have a cut in the top middle so I can access the bolts. With the engine running I open the valve until I hear it ticking and then slowly close it until ticking stops and give it another quarter turn for the preload.