My son and I are working on a 66 F-100 2wd with auto trans and a 352 engine. The truck had sat for years in a flield. Last week the oil pressure started going from 0 to 45 psi. Pulled the valve covers and fond that 10 of the valve seals were gone. We used a string in the cylinders to hold the valves and a old rocker arm shaft to pry on and pulled the valve springs. Replaced all the seals. Then pulled the oil pan to clean the pump screen. Took about 10 hours to do this. Pressure is now at a steadly 45psi.

 

another trick i have used is air preasure to hold the valves in place

 

What do you do if you lose air charge in the cylinder & the valve drops? Clothesline or thick venetian Blind cord are the only fail safe way to hold valves up when swapping stem seals IMHO.
Bertha 66 Did you check inside your rockershafts and oil galley in rocker pedastal seat to see if there was any build up in there too? Generally when your screen & pan get sludgey these other places seem to be sludgey too. . .

FBp

 

[
Bertha 66 Did you check inside your rockershafts and oil galley in rocker pedastal seat to see if there was any build up in there too? Generally when your screen & pan get sludgey these other places seem to be sludgey too. . .

FBp [/QUOTE] Yes, we did checked oil drain holes and cleaned around the heads. I will short change the oil to see if anything else comes out.

 

If when you change the oil, you get any hard black rubber pieces from disintegrating valve stem seals, I HIGHLY recommend you pull the oil pan.
Those pieces get sucked up into the oil pickup screen, and plug it up, especially at higher RPMs such as at cruising speeds. Worse, they don't fall back out when the engine shuts off. They tend to stay stuck up against the pickup screen, due to the limited clearance between the screen and the bottom of the oil pan

You can pull the oil pan and replace it in about 3 or 4 hours, going slowly, without removing the engine. I got good enough to do it in an hour and a half. Jack it up and place 2 short 2x4s under the mounts, and that will give you just enough room to pull it.
Watch the following things:
Remove the accelerator cable, otherwise it will get pinched.
Watch the radiator hoses, that you don't put too much strain on them.
Watch the auto trans lines; they should be OK though.
Drop the pan onto the crossmember, remove the oil pump - working with the pan still in place - and then remove the pan and pump together.
(To re-install it with the pump in the pan will be a bit difficult, but it can be done.) I recommend you seal a new gasket to the oil pan with a very thin coat of RTV, but with no RTV between the gasket and the block. I like to clean the pan and seal a new gasket to it right away, and give it time to harden. It makes it easier to re-install the pan that way. Be sure to keep the pan bolt holes clear, too.
When re-installing, make sure the oil pump is fully seated against the block before tightening the bolts. Otherwise,the pump driveshaft may not seat correctly, and you will run the engine dry, or you may break something.

By the way, since you are removing the oil pan, this would be a good time to replace the timing gears and chain, if you are so inclined to do the extra work.

Hope this helps!

 

Yes we did pull the pan, and cleaned it out. Unbolted the engine and lifted it with a cherrypicker. Unbolted the radiator and hung it with a bunge cord to the cherrypicker, that way no strain on the hoses and trans lines.

 

Kewl!
Never heard that way before, and I bet it worked really slick.

(By the way, I should have read your first post better!)

Just out of curiosity, did you find a lot of crud in the pan?

 

We did find alot of crud, but it was all rubber from the seals. as far as we can tell the truck only has 40000 miles on it. The inside on the engine is very clean. Hooking the rad. to the cherrypicker worked real good.

 

Word of advice...
Had the same problem. Twice in two months. Broken valve stem seal pieces got in the pump, locked it up and twisted the oil pump driveshaft in two. Twice.
When you pull the pan, pull the pump and take the pick-up screen off and tap it on a piece of wood. You'll see the valve seal bits fall out that are lodged under the flat piece of steel that runs across the screen. There is a hole in the center of the screen, under the flat piece of steel, about a half inch across. That's how the chunks get in and compromise the pump.
After the second time aroound, I replaced the heads with a spare set I had rebuilt, making sure to check the valley for any remaining bits of seal. I pulled the pan, replaced the oil pump driveshaft (again), took the plate off the oil pump, cleaned the gears and reassembled the pump. This time, however, I drilled tiny, tiny holes in the flat steel piece on the screen and twist-wired the hole in the screen to the flat piece of steel. Thus, making it harder for the seal bits to get to the pump gears.

 

Good advice, I did pull that screen and clean it.I did not know that the screen had a hole in it, but I did not pull the screen out.