Tore down the valvetrain on the 81 4.9 the other day to track down a minor "tick" under engine load. I have the non-adjustable, pedestal-mounted rocker arms with the 3/8" nut. I found wear on the rocker arms where the contact the valves (going to replace rockers, fulcrums, and the nuts) (valve contacts look fine), and one lifter somehow lost its retaining clip that holds the plunger in (guessing that was the source of the noise). The lifters are otherwise fine, no dishing or pitting, just need a good cleaning. I stole the locking clip out of a new lifter and used it to reassemble the original one missing it, so that I can reuse the originals with a cam that appears to be in good solid shape.

I have 2 questions:

Should I put the lifters back in dry, or presoak them in engine oil? I have heard mention of compressing them, or disassembling and cleaning them to make sure they are compressed. Does this just mean that they have no oil in them?

Been awhile since I messed with these non-adjustable rocker arms, do I really just tighten the nut down to specs and thats it? Does each cylinder need to be at TDC compression for this, or does it matter with non-adjustable rockers?

 

I would soak them in oil and maybe pump them with a dowel or broom handle.

When installing the rockers I would think you would want to have no load on the valves. There should be some info somewhere that shows the pattern to adjust valves on that motor. When the crank is in such and such position torque these valves. Then rotate 180° and tighten these and then 90° and tighten the remainder.

 

Try to put all of the components back in the place they came out of. It isn't mandatory , but those components have worn together and matched themselves.

 

The lifters need to be installed collapsed, which means minimum adjustment. Tighten the rocker nuts down at TDC. The valve train should be loose at this point so you are just torquing the nuts and not compressing the valve springs.
Oil press will fill the lifter causing them to expand and remove the slop in the valve train. I would do a crank the engine over to build up oil pressure instead of starting it with a loose valve train.
Jim

 

OK, so put the lifters back in dry, in the same locations they came out of. When you say they need to go back in "compressed" does that just mean empty of oil, or do I need to somehow press and hold the plungers down in there somehow?

Then, reassemble the valvetrain loosly, rotate each cylinder around to TDC on the compression stroke and torque the nut to specified amount (in firing order)? Anyone recall that amount?

 

You will still disassemble, clean and test each lifter, just be sure to install them without pumping them up. You want the internal lifter piston bottomed out when you install them.

I am sure there is a You Tube on how to clean and test HYD lifters.

I would torque them at TDC, but if the valve train is loose it would all work out the same.

The maim point is the valve train need to be loose so engine oil press can push the piston up in the lifter to take up the slack. If they are not loose you are holding a valve open all the time.

Be sure the studs have not pulled out of the head, before and after tightening the rocker arm nuts. I think the torque will be around 20-25 foot pounds, but I don't have an exact number.
Jim

 

I don't know what all the fuss is about. What I would do is put a smear of moly lube on the face of the lifter and on the cam lobes if you have pulled the cam. If you haven't pulled the cam, just put a smear on the face of the lifter.

I would not worry about whether there is oil in the lifter or not. And don't worry about where the engine is located as far as firing. That's the only advantage to these non-adjustable lifters, and no one is taking the advantage. You bolt them down and run it. There is no adjustment. Any adjustment is automatically done by the lifter. It may run a little rough for a minute or two till the lifters get adjusted, but they will do it by themselves, there is no way you are going to predict how much oil will be in them and no way for you even to get it in there.

 

Got a little side-tracked with work, and had to put this project on the back burner.

Just put a 3ft level across the rocker studs, and I have one on cylinder 5 that has pulled up pretty good. I know how to pull it out, but is there any trick anyone knows of to press a new one in with the head on? I know it would be better to just switch over to threaded studs, but I don't really have the time or patience for that right now. Is there a threaded stud that will accept my stock non-adjustable rockers? I'd be willing to go that route on this one stud for the time being.

 

Here is another current thread with the same problem.

https://www.ford-trucks.com/forums/1304842-uh-oh.html


I have often wondered how long it would last if you just pounded the stud back down.

 

Well, I did have another one that poped up a couple of years ago, but I didn't just pound it back down. I pulled it out and pounded in a new one, with a light coating of red loctite. That one hasn't given me any more problems. I'm just wondering if there is a way to actually press a new one in (with head on engine) instead of beating it in there. The first time I did it, I had the nut on top of the stud, and used a block of wood, and the threads still got messed up a little bit. If this was my DD I wouldn't even be thinking of doing this kind of repair, but she is just a weekend warrior work truck. If somebody makes a screw in stud that will accept my original-style rockers, I could tap the hole, and just run it in until the collar where the fulcrum rests was at the same hieght as the rest of the studs. Anyone know if such a stud exists?

 

Who does engine work in your area? I would call them and see what they say. They probably know what you are talking about, and may be able to get a stud for you or may have another idea they use.

 

previous owner of my truck did that it works till you hit about 2500 rpms

i got the head off of and 80 f100 and the rockers bolt into the head no studs i would go to the jy and see if you can find one i have also herd of using helicoils but that sounds like a lot of work