Before I start turning the motor over to get my lifters on the base circle should the rocker nuts be loose or tightened?

My builder set my lash but I need to go through it again...I don't know if I should go around to all the valves and loosen them up or just start to get #1 intake on the base circle THEN loosen the nut and tighten it back down and so on for each other valve

Im trying to do this right now too...

 

i've never had to loosen anything first and i'm not sure why you would need to?

 

Makes no difference.

 

Doesn't matter.

Easiest way to be accurate, is to look at the motor, and observe a valve that's nearly all the way open; let's say, #6 intake. Turn the motor until it reaches exactly full opening. At that point, the same valve on the cyl 4 cyls away from it in the firing order, will be exactly on its base circle (#1 intake in this case). Adjust #1 intake. Rotate engine exactly 90°, now the next intake valve will be exactly on its base circle; and so on. Then when you're done, do the same thing with the other kind of valve. Add your desired preload somewhere along the way, either as you do each one, or zero them all then go back and preload them all. I'd suggest ½ turn. This method is accurate enough for solid cams; you can do it this way, and confidently install the valve covers permanently with gorilla snot, even on a solid cam.

You can get as accurate as you really need though, by the "EOIC" method. To use that one, you rotate the engine until a cyl's exhaust is just opening ("EO"), and adjust the intake at that point; then rotate it until the intake is just closing ("IC"), and adjust the exhaust at that point. This method is plenty accurate enough for a hydraulic cam; it will get the lash easily within 1/8 turn or so.

The "Chilton's" method of set the engine here & adjust these 8 valves, then move it there and adjust the other 8, is useless for anything bigger than a stock cam such as the "peanut" cam or the 929 cam.

 

Thanx for the quick replies guys. As some know I've had a tough time lately with the car.
I guess I'll go get the lifter on the base circle, then loosen the Allen head lock, then loosen the rocker nut, then tighten to spec and lock it down :talking to myself:

Im going to try the EO/IC method first and then go from there.

 

hmmm.....so I can get zero lash just fine but when I go to preload the rockers (#1 Intake only so far) before I reach evev a 1/2 turn it tightens too much to where I can't spin the pushrod with my fingers anymore??

Any idea why it would do this?

 

yea its tight at a 1/4 turn and the pushrod no longer spins with my fingers.
I tried to remove the lash cap and try again but with the same result.

 

Lifter is full of oil.

Doesn't matter.

Just BE SURE that when it's at "zero lash", that's the point at which the play between the lifter and the rocker is taken up; that is, the push rod just barely doesn't bang up and down between them. "Twisting" is a VERY BAD way to find zero lash.

 

Yea, I'm doing the up and down method to get zero lash and I'm fairly comfortable with that but it just tightens up so much at 1/4 turn more it worries me.

So you say its no problem...go ahead with another 1/4 turn even if the pushrod won't spin freely after its all set 'properly'?

 

Yup.

 

Cool well, I'll go knock them all out.

Any idea why the pushrods still spin on the other valves I havn't touched yet? Did my builder not preload them correctly?

I know when he assembled the motor (heads and valvetrain) the lifters were new and he did not pump them up...

 

They get pumped up from running. Once the motor has been started, doesn't too much matter what the builder did to them.

The ones that you can spin easily, have probably been sitting there compressed, and have had the oil leak out of them; the ones you can't, were on the cam base circle while the motor has been sitting.

Nothing unusual or to worry about.

 

Thank you again...I'm learning quite a bit here lately!


I did run into yet ANOTHER problem but I think I fixed it. The Allen Set screw inside the #1 Exhaust Poly Lock was EXTREMLY tight.
I mean with the rocker nut off the stud I had to put the rocker nut into a vise and with everything I had unsrew the Allen set screw. I thought it was stripped but after some time it broke loose(r). The rocker nut actually heated up from the friction and while the set screw still has a lot of resistance (doesn't feel like a bolt spinning in a free threaded hole) it will work I think.

 

If that happens again, put an open-end wrench on the stud, a box wrench on the nut, and an allen key in the set screw; and back the nut off, while holding the stud still. Don't even mess with the allen as long as it turns with the nut. If the allen doesn't move, turn the allen key and the wrench on the nut together, to break it all loose.

Likewise, when you tighten them, put a box wrench on the nut, and tighten the allen conveniently tight with the key; then tighten the nut and the allen together a bit. You'll never get the allen tight enough, all by itself, to hold reliably; but if you tighten the nut and set screw together, you can get it probably 5 to 10 times as tight as the allen by itself, without working hard.

I hate work...

 

Yup, I got the drivers head done and went 1/4 turn from Zero lash and about another 1/8 turn while turning the set screw and rocker nut together to make sure they are plenty tight.

Might have a big problem though, again, of course...

If you remember my lash cap falling off on the #2 intake valve; well, I just inspected it. The rocker has hit the retainer somehow!!! The rocker is nicked up underneath and the retainer is scratched up. Nothing is really bad, and I'm even thinking the lash cap might have done it because none of the otehrs have interference problems.

Any Ideas or suggestions where to go next?

 

Well it's not impossible then, that you just found the source of your oil contamination.

The retainer is probably not hurt, or the rocker.

Check closely to make sure that the rocker geometry is correct, and that the whole thing can't fall apart again. If it's all like it's supposed to be, then probably the lash cap got loose as the motor was being assembled, and that's why it came out.

Careful and thorough inspection is your friend. You have 7 others that work; just make sure this one is EXACTLY like all of those.

 

Everything seems to be in order...take a look at these pics. The damage doesn't look too awefully bad but do you think all that metal I was getting could have been from this?

 

No, probably not. Doesn't look like much metal is missing from those parts. They're not really hurt. Unless the lash cap is chewed to nothing, which is highly unlikely; they're usually pretty hard.

How about the push rod and guide plate? They OK?

 

pushrod and guide plate check out. the lash cap didn't really have a mark on it

Apieron said I have the wrong keepers for lash caps...I didn't know there was a difference.

If I remove the lash caps altogether will that cause inproper geometry in my valvetrain?

could I have possibly wiped out my roller cam somehow???

 

Tight enough to see it move..?

 

Well I've never used lash caps on an SBC, so I don't know, but I've used them on a net-lash OHC engine, and the keepers have to be changed for the grooved ones.

If you remove the lash cap, you should check the geometry.

 

Tight enough to see what move?

Best case senario, the lash cap fell off because he over looked that valve or it loosened during assembly, the metal is just excessive break in material (my cam is fine and the timing set isnt hitting), and this new chip will get it to idle...

Worst case, I just wasted 6 grand.