5.0 hydrolic rollers: No Adjustment and need some advice.

[skullandbones]

I'm getting ready to do a first startup but I may have a problem. I'm not sure about the valve clearance on my hybrid engine.

I have a crate engine that came as a long block with E7 heads. I changed out the heads with GT40Ps that I reworked and had machined. The shop had to take off 20 thousands from the deck because one head was a little off. I used the valve springs and hardware from the E7 heads that was recommended by the builders since they were matched to the cam (E cam). I also had some new Crane alum rocker rollers (pedistal base) F3ZE-6529-AB that were on the GT40P heads on another engine when I got them. These are Crane but with a Ford logo so they are sold through Ford Racing. Usually, the issue is that there is not enough clearance which shows up as too much preload on the lifters. I think the acceptable range is 20 to 60 thousands of preload after the bolts are tightened down. I have checked a couple of cylinders for this "preload" but cannot tell because after tightening down the bolt, I can still spin the pushrod. So instead of needing a shim kit to raise the pedistals, I think I may have the opposite problem.

That leads me to the question: Do I need to have the lifters full of oil before this test can be done or should the "preload" test be done with the lifters dry?

Also, if I really do have a problem how is it best resolved. I'm thinking that I may need longer pushrods. The only other thing I can think of is to have the pedistals machined down the appropriate amount if that feasible. I think the longer pushrod solution would be the simplest way if necessary. So what's the verdict? This is the first Ford engine I have worked on so I need some help from the forum. Thank you. WEK.:confused:

[Mustang Man]

Do you have the intake off? I usually measure the lifter preload at the lifter plunger after tightening to zero lash plus 1/2 to 3/4 turn. If the plunger is too deep you need the shims under the pedestals...

HTH...
Mark

[Mike N]

Don't panic. There is a piston in the hydraulic lifter than is spring loaded that is designed to accommodate the preload of the pushrod. I would be more concerned if you could not spin the pushrod as that would mean that the piston is bottomed out in the lifter and you are hanging the valve open. If you can spin the pushrod but cannot feel any vertical slop then you are probably fine. While adjusting the rocker stud you should be able to feel a change in drag when spinning the pushrod indicating that you have taken up the clearance. At that point you should be able to turn the rocker nut another complete turn or so before tightening against the pedestal. The ideal would be half to 3/4 of a turn. By the way make sure than the lifter is on the base circle of the cam and not on the lobe or ramp.

[skullandbones]

Maybe I need to start over. First, there are no studs and nuts. This is a bolt in rocker setup with no adjustment. The valves I have checked (pushrod will spin with bolt down tight) there is about a 25 to 30 thousands play in the roller rocker arm. So you can feel very slight movement up and down in the rocker arm. No, lower intake is already bolted down. So should I be checking this system without oil or does that matter? I am not worried about the valves hitting the cylinder. I am not sure if I can get the "slop" out of the rocker arms bolted down tight. That's my problem. Sorry for not making it completely clear. WEK.

[JimmyZ]

Deleted

[Bob Cowan]

Pedestal mount rockers were developed to make initial assembly at the factory idiot proof. Once things have changed - like in your engine - that stock assembly technique is no longer valid. If you simply follow the Chiltons manual and bolt them down, bad things could happen. Expensive things.

Obviously, the best option is to mill down the pedestals and use screw in studs, guide plates, and matching roller rockers. For the cost and hassle, it's probably not worth it to you.

You need to be able to measure and adjust the pre-load properly, without a lot of hassle, expensive equipment, and engine disassembly.

Since you've milled the heads and used a thinner head gasket, the rocker is now about .030" or so closer to the cam shaft. You would need to shim the rockers up a smidgen, or use shorter push rods. Shims are generally cheaper and more accurate.

The correct adjustment for a stock Ford hydraulic roller lifter with a stud is Zero Lash, +1/2- 3/4 turn (give or take a little). Aftermarket and modified stock lifters may need something differant, so be carefull there. In the olden days, you found zero lash by tightening the rocker arm nut until the push rod would not spin. With modern materials and oils, that doesn't work any more; when properly adjusted you can often still spin the rod with your fingers.

With the lifter on the base circle, tighten the bolt by hand, until you can't turn it any more. That's zero lash.

Now, put a dial indicater on the tip of the rocker arm aligned with the push rod. Tighten the bolt to spec, and see how far the tip drops. That's your pre-load. Your goal is 0.030" If you have more, you need to shim the rocker arms. If you have less, you need longer push rods.

Also, with all your modified and aftermarket parts, be sure and check rocker arm alignment on the valve stem at the same time. If your pre-load is perfect but your alignment is way off, you have a problem.

Because I'm a bit OCD, I check every rocker arm, during every assembly.

[skullandbones]

[QUOTE][/QWith the lifter on the base circle, tighten the bolt by hand, until you can't turn it any more. That's zero lash.

Now, put a dial indicater on the tip of the rocker arm aligned with the push rod. Tighten the bolt to spec, and see how far the tip drops. That's your pre-load. Your goal is 0.030" If you have more, you need to shim the rocker arms. If you have less, you need longer push rodsUOTE]

Bob, that's what I can't do because I don't think I have zero lash when the bolt is snugged down. It's not just that the pusrod spins with your figure pressure, there is more play than that. That's why I was asking if the lifters need to be full of oil for this test to work or not. I don't know. I will be very careful going forward. That's why I asked in the first place. I don't normally have OCD tendencies but when things just don't add up to my understanding, I get very OCD like. I will check how the roller rides on the valve stem. It looks like it's OK but I know you have to do it with the indicator and tighten it down and then take it apart an see where the mark is on the valve stem. Thanks for the heads up. I would really appreciate it if you or someone else can tell me if it is necessary for the lifters to have oil in them, though. Thank you, WEK.

[rich grsc]

No one has answer your question, the lifters need to be full of oil.

[Bob Cowan]

The job is a little easier if the lifters have NO oil in them, but it's certainly not a requirement. With or without oil, the lifter will compress long before the valve spring will. I find it easier to make these measurements without oil in the lifter - but it does take a very carefull and steady hand. Some people prefer to have oil in them, as it buffers down movement and provides a steadying influence - although a slightly slower response.

If you still have slack after the retainer bolt is torqued to spec, that means your push rods are too short. You could measure how much slack you have, and adding 0.03", you can tell pretty close how long the new push rods should be. Probably. If you're very meticulous with your measurements.

But, the job will be a lot easier if you get a pair of these adjustable checking push rods: http://www.summitracing.com/parts/CRN-99727-2/ Pick the ones that match your current push rod length. A the same time you're measuring for length, you can also check alignment, and then order the exactly correct push rods.

As for OCD, I think that's a good thing. Carefull checking and measuring at each step, and a thorough understanding of every step is important to good success. The devil is in the details.

[skullandbones]

I appreciate everyone's posts and feedback. Now I can go forward with a plan. I was going to mention the adjustable pushrod scenario (saw in Summit catalog) but wasn't sure because I am not sure I can get a pushrod exactly the right length if it is too close to the stock length. But getting a longer pushrod will probably work best for the alignment of the roller on the valve stem. So that will be my first pathway. Thanks for your detailed explanation (Bob) and thank God for OCD!!! WEK.

[Bob Cowan]

The adjustable push rods usually come in a set of 2. You assemble the valve train with those push rods to find the exactly correct length that you need. Then contact your favorite manufacturer and have the correct ones made for you. I got lucky, the correct length for me is the same as a stock small block Chevy. I can use off the shelf parts.

[Mustang Man]

This is why I asked if the intake was on yet. Measuring, checking the lifter, adjusting the pushrod, etc. is all much easier to do with the intake off and you can SEE what the lifter is doing...

Good luck with it...
Mark

[jetsbaby]

If you want you can borrow my Comp Cams degree wheel and push rod length checkers I have..I also have valve spring compressor tool to remove springs while still on the engine..I have a lot of specialty tools for building engines since I built my own and wanted do learn to do it my self. I live in Chandler AZ..Dave

[skullandbones]

I understand what you're saying Mman. I may have to resort to that tactic if I don't get it figured before that. I have just ordered a pushrod checker from Summit today. Jetsbaby, thanks for the offer but I will try the checker first and see where I am with this. By the way, did you have any issues like this?

Bob C: took your advice and ordered the checker. It's a good idea to use a stock item like the Chevy pushrods. I have gotten estimates on custom pushrods from $85 to $159 so far depending on the exact length and manufacturer. I will look for the stock product when I find the right length.

I also spoke with the machinist that worked my heads. I knew he milled them a little but he said he only took off 10 thousands so he didn't think that would be worth worrying about. However, I don't know if the head gaskets I used were the same thickness as the factory and I also don't know if the lifters will change the measurement of the pushrods. I don't want to take a chance that it's OK as is. Oh well. I'll do some other task until I can come back to this at the end of the week. I will keep you posted. See you later and thanks again, WEK.

[skullandbones]

Hey, I got my pushrod length checker today from Summit. Out to the garage to do some measurements.

Man they have got the shipping thing down! I would call them "world class" in that department.

WEK.