Rocker install

I just bolted on my new gt40p heads and am reusing my old rockers, lifters and rods. Do I need to check the rocker to valve clearance? Is it possible I may need different length pushrods? Do I need a lifter compressor tool to check the clearance between the rockers and valves?

ok, the ford power manual described a technique using a lifter compressor tool. In that crane desription they just torqued them waited, made a mark and took the torque off and measured the change. Correct, seems much simpler.

yes, I was wondering about the shims. I have no shims now, I just took the stock rockers, rods and lifters off the old heads and put in the new. In the same order and piston position of course.

I am also correct in thinking that the only way to reduce the preload if it is too high is to get shorter rods. Right?

Those comp directions are the same seems to be the way to do it.

ok I will go mark everything, by base circle you mean on top of compression stroker? Valves closed?

To increase preload I will need to get longer rods, right? just ordered a shim kit.

gotcha, thanks tim!

ok so I need some more advice here. I followed the instructions and giving and I noticed that according to the scribe marks they were pretty consitently measuring around .090. So too much preload so I was put .060 shims in and started noticing after the shims were in when the valves were closed the rockers were real loose.
I can spin the pushrod and actually then I noticed I could rock the rocker back and the pushrod back down by hand. Is this normal? am I doing something wrong. When I took them off the old heads they were not this loose. Thoughts? advice?

are these new lifters?   They may need to be pumped up and try again. tightening the rocker down with out oil pressure can force the oil out of the lifter.   Do you still have the intake off, if so pull lifters out one at a time, submerge in a can of oil and pump them up using a pushrod. Reinstall and see what happens.

There's a point where you have to trust your measurements, if you have confidence in them then button it up and fire it. You'll know right away if they're loose but my guess is they will pump up and be fine. Easy enough to check again after you get some oil pressure in the engine.    You could also spin the oil pump with a priming rod and check again but if you trust your measurements just fire it up.

The one with no pre-load, maybe a collapsed lifter?

all I'm suggesting is that if you had to shim that much than when you tightened then down the first time and took your measurements without any oil pressure in the engine you may have pumped the oil out of the lifter. Again if you trust your readings fire it up, worst case is you have some lifter noise and you need to repeat the procedure. Once you pump the lifter out the plunger will still return to the top but it's hard to get a good read on them because they are soft until oil pressure returns.

This is fairly simple so don't overthink it, I would fire it up and you'll know right away. If you've shimmed all worse case is you'll have a little noise, too tight and you'll have a bad idle but I don't think that will be the case. If you're not sure just check them again after you run the engine a few minutes. I also don't like the scratch and measure deal so I use a dial indicator with a magnetic base and get real numbers.

This is why I love stud mount adjustable rockers!

By the way a quick tip for finding tdc on all cylinder and the way I do mine is to get the motor on TDC of #1 on the compression stroke. Then mark the balancer with chalk or white toe nail polish if that's your bag at 90 degree intervals. Measure your pushrod length at #1, then rotate the motor in it's correct direction 90 degress or a 1/4 turn to the mark on the balancer. Go to your next cylnder in the firing order and that cylinder will be at TDC, do this 6 more times through the firing order and your done.

i always like to keep the cordless drill in the distributor hole to keep pumping up the lifters, its a 5/16's hex to prime the pump, pretty much a sure hit so the lifters dont bleed down, even though they really shouldnt

Okay, so I'm a number of steps behind and I'll need to read through the procedure several times as I don't yet know where the shims go, where you are measuring, etc. So I'm sure I'll be asking lots of questions.

But, can someone please explain to me about the drill in the distributor hole and how to pump oil that way? First, I want to make sure the lifters are all full when I do my measurements and adjustments (shims as needed), and secondly, if this is somehow running the oil pump and I can pump oil through the engine while off, that would be great (I could do that just before reinstalling the distributor and firing it up).

Thanks. Ordered. How does it work? Is it turning the oil pump (don't know how that is possible)?

slmskrs wrote: Thanks. Ordered. How does it work? Is it turning the oil pump (don't know how that is possible)?

Normally the camshaft turns the distributor shaft, which in turn, turns the oil pump.

Now, with this distributor out, you are putting in this tool, and attaching it to the oil pump, where the distributor shaft normally goes.

And, instead of the camshaft spinning the distributor shaft, your drill is spinning the tool, which will turn the pump.

It's kind of like when someone has a cardiac arrest, and the surgeon reaches into the chest cavity and squeezes the heart by hand to make it pump

hahah what an analogy!!!

the shims go under the rockers to lift them up, this relieves some of the tension from the lifters when the valves are shut. Just google rocker arm adjustments or preload and read up on the idea. You dont want too much or too little.