85 f150 300 6cyl, holley 4160 clifford intake. put a reman head on it and new lifters pushrods and rocker arms. Problem is i have this loud very fast knocking noise. almost sounds like pinging sound (marbles rolling around in engine) but i really dont think it is ping. it happens at 2700 rmp. My old rocker arms when you would grab them and try to move them side to side there would be no movement at all. the new ones when i installed them and 500 miles later now still have play in them. Not alot where you can grab the pushrod and wiggle it, you physically have to grab the rocker and make it move. There is no lash adjustment from what i gather, bolt down rockers. all were torqued to spec 3 times. even tried a little further past torque setting still nothing and loose. I believe this is my noise at 2700 rpm and above. could it also be that the lifters i put in are not agreeing with the cam and cant break in correctly?? all the parts on it are for an 85 f150 but i cant understand why the rocker arms have play in them.

 

This engine uses hydraulic lifters. They self adjust. Oil fills the lifter, and that takes up the slack. If the engine sits, the lifters can bleed down, so just "wiggling" the lifters is not a good test.

You should have no trouble with this setup, the rockers should bolt down and go. But since you put a rebuilt head on it, a lot of things can go wrong if the people who rebuilt the head didn't do their job correctly.

The "bolt down and go" theory only works when everything is kept to factory specs. When the valves are ground, and or the valve seats are redone, this changes the height of the valve stem as it sticks out of the head. This will push the rocker over, and push down on the pushrod. What they are supposed to do to prevent this is grind the valve stem tip the proper amount to bring it back in. If they didn't do this properly, the pushrod can be too long or too short.

Also if they resurfaced the head where the head gasket goes, this will bring all the valve train down closer to the block, and make all the pushrods too long.

I have never worked on a six, but on the v8's to see if the valve train is correct, you turn the engine over to TDC, so both valves are shut on #1 cylinder, and then you loosen the rocker arms on #1 cylinder, and then you wiggle the pushrod around while tightening the rocker bolt till the slack just leaves pushrod and then stop. You then tighten the bolt, paying attention to how many turns it takes for the bolt to seat. You want the lifter to be in about the middle of it's travel, and I believe this is 3/4 to 1 turn after all the slack goes out of the pushrod. If you can't get the slack to come out, or it's only like 1/4 turn till the bolt stops, that pushrod is a little too short. If it's much over 1 turn, that pushrod is a little too long. You need to turn the engine and check each cylinder when the valves are closed for it.

If any of the pushrods are a little long, you can fudge it by adding a small shim under the pushrod pivot sled. If the pushrod is too short, you pretty much need a longer pushrod, and I believe Ford used to sell them.

 

FRANKLIN THANK YOU FOR THE QUICK REPLY. GOOD INFO TO THINK ABOUT. ON MY TRUCK THO, THE ROCKERS ARE NON ADJUSTABLE. THEY DO NOT HAVE A NUT AND STUD TO ADJUST LASH. BOLT DOWN TYPE ROCKERS. JUST TORQUE AND GO. LIKE YOU WERE SAYING THO OF TAKING OUT THE SLACK. I HAD THE ROCKERS ON #1 CYL AT TDC AND I ACTUALLY TIGHTENED THEM DOWN AS FAR AS I COULD TURN THE RATCHET AND IT STILL HAD THE PLAY IN IT. I THINK I NEED LONGER RODS. I DONT SEE ANY OTHER EXPLANATION? WHAT DO YOU THINK

 

I know you have non-adjustable rockers, that is what I was saying. And even though you do not have adjustable rockers, they still work the same way.
So if you had an adjustable system, you would turn the engine over to TDC on #1, take the slack out, and then turn it 3/4 to 1 turn. Your engine works exactly the same way, except your bolt is supposed to bottom out at 3/4-1 turn. So what I was saying is to test it out like you do have a adjustable valve train, just to see where you are at.

Your valve system works the same way as an adjustable system, but you do not have a choice to when the bolt stops. That's what you need to check, how many turns before the bolt stops.

 

ok. i read this when i was at work and read quickly didnt really catch all you said i guess. i'll take a look at it thanks

 

How's your cooling now?

 

hey thanks for askin. i got it figured out, i had the wrong fan on it. i used the fan from a 89 serp belt sys. put the right one on and never goes above 180.