Fuel pump push rod bushing 8BA

GreenMonster48

GreenMonster48

Well-known member
Is there a way to replace the bushing while the engine is still in the vehicle, or do you have to pull the motor out to successfully get at it?
 
When I drive my truck more than 5 or 10 miles, oil gushes out of the fuel pump stand. I've replaced the gaskets and put tons of sealer on them. I assumed that the fuel pump rod bushing was really worn out so lots of oil was getting by, or that they put the wrong fuel pump push rod in. I was going to try just replacing the push rod to see if that worked, but I wanted to be prepared in case that wasn't it...
 
I'm assuming this is an 8BA style engine. If you have sealed the pump stand and pump mounting, how is the oil getting out? Is your breather piping open and allowing ventilation? These busings are rather thick and of hard material. I have never seen a worn out bushing in all the engines I have disassembled.
 
I agree with Jack---I have never seen a bushing worn excessively. The bushing has only a .0625 hole to meter oil so even if worn I would wonder how the oil could climb as described?

I have a puller for the 8BA bushing, which can be used with an assembled engine, if the intake manifold is removed. But again, I doubt the bushing is a problem.
 
The road tube and the breather flow fine. The oil just seems to seep out of there. After I drive it for a bit it seems as though the oil gets trapped in the top end of the engine and wont drain back down. When I had the intake off, all the drain back holes seemed to be clear.
 
could you be building pressure in the engine, breather pipe open, do you have a PCV valve installed? what is your oil pressure like, when it is hot, most worn bushings cause the oil pressure to fall off rapidly after the engine is warmed up
 
A worn bushing will have no impact on oil pressure unless it has a hole worn in the middle of it. Almost impossible.
 
Check to see if the fuel pump stand housing base is warped. If it is, It will not tighten down on the middle portion of the gasket and it will leak. Here are some pictures of a flat base bolted to a warped one. The bushing is hardened steel and should not wear.

Jerry
 

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You are so right flat head fever. Caused by incorrect installation of the gasket and baffel tube. The gasket must go on the manifold FIRST then the baffel tube dropped in. The flange on the top of the tube must be ABOVE the gasket to seat in the recess of the oil fill casting on the bottom of it.What you show is beond repair,its toooo warped you could never straighten that one out. Thanks for showing the pics. ken ct.
 
But that's not whats happening here. It's not just leaking out of the base gasket, it's leaking out of the side gasket where the fuel pump mates to the pump stand (remember this is an 8BA). It's clearly a pressure issue, I'm just trying to figure out where the hell this oil is coming from, why it's staying up there, and how I can fix it. The motor is ALL STOCK except for headers. No PCV or anything, and as stated before both the breather and the road draft tube flow freely. I do have a considerable amount of blow-by as the engine is tired, but I don't think that would necessarily cause such an issue. I've been scratching my head for months!
 
GreenMonster48 said:
But that's not whats happening here. It's not just leaking out of the base gasket, it's leaking out of the side gasket where the fuel pump mates to the pump stand (remember this is an 8BA). It's clearly a pressure issue, I'm just trying to figure out where the hell this oil is coming from, why it's staying up there, and how I can fix it. The motor is ALL STOCK except for headers. No PCV or anything, and as stated before both the breather and the road draft tube flow freely. I do have a considerable amount of blow-by as the engine is tired, but I don't think that would necessarily cause such an issue. I've been scratching my head for months!
Click to expand...

You may have answered your own question when you said it had excessive blow by.
 
do you have the short interior pipe in the front of the lifter valley that connects to the front underside of the intake manifold? this pipe takes the crankcase blowby pressure and connects it to the intake manifold then out the road draft tube. just a thought...
 
I may be wrong here since I'm not all that familiar with the 8BA but shouln't there be a skirt on the push rod to stop oil from coming up to the fuel pump? Just a thought.
 
Have you ever cleaned the main oil galley passage? There is a cast passage that runs the length of the block above the cam that has plugs on the front and rear faces of the block. If this passage is blocked, then the oil has nowhere else to go but up.
 
Do you have both the forward INNER vent tube, the one inside the valley JDL mentioned, and the little sheetmetal clip-on baffles that go along the middle floor of the valley? If any of that stuff is not there, too much oil gets tossed into the valley from below and multiple problems result.
 
You should also check the breather/filler cap to see that it is not clogged. If you have a lot of blowby, maybe the screen is clogged and not allowing proper ventilation.
 
And another strange clogging point...some late engines have a little filter inserted into the draft tube where the upper and lower tubes clamp together.
 
If you think the valve galley is full of oil,I would think you would have ran out of oil to the oil pump. If the oil is staying in the upper end ,I'd be more concerned about getting those passages open. I feel your problem has more to do with fuel pump rod,pump ,mount,or gasket. Ever know what people before you have done to your motor.You don't want to mess with that bushing. thats a whole different bucket of worms.Good luck with the oil thing . keep us posted.
 
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