Oil Leak At Fuel Pump

[67GTX440]

I have an oil leak at the fuel pump and I am trying to determine the likely cause. Should I replace the fuel pump gasket to the block or the gasket and fuel pump as well (since the fuel pumps are pretty cheap) as a start? I am not having any fuel issues. Has anyone had the problem with the replacement fuel pump design being different so that the bolts are too long and cannot adequately tighten up? Could this be a PVC or breather cap issue? The oil level it at or just above the full line. Will over filling cause this to leak at a vent hole?

I keep reading that old Mopars have a lot fewer oil leak issues if the oil level is kept at the 1/2 quart low level than the full level. Any truth or risk to this?

 

[Cranky]

Never had any problems with over filling my oil but 1/2 quart never made anything leak. Do you have a PCV system hooked up? If not, this could cause leaks in places where it shouldn't. Is it blowing the dip stick up out of it's tube? The fuel pump has special bolts....the heads are just a bit rounded for ease of getting a socket on them at a slight angle. If your PCV system is right, I'd try a new pump to block gasket.

 

[TxDon]

Beautiful car! IMO if your fuel pump is old or of undetermined age I would replace it since you have to take it off to do the gasket anyway. I would also replace the filter and any rubber fuel line at the same time as cheap insurance. I can't speak to any of the other questions from experience but deliberately running any engine low on oil capacity sounds like a bad idea.

 

[RT K_line]

I would replace the fuel pump at this time also. Most fuel pumps have a weep hole that will leak oil if the internal diaphragm ruptures, this could also dilute the oil with fuel.

 

[Cranky]

I would replace the fuel pump at this time also. Most fuel pumps have a weep hole that will leak oil if the internal diaphragm ruptures, this could also dilute the oil with fuel.

There's usually not much pressure behind the pump and if the diaphragm is ruptured, the oil will be diluted....at least that has been the case whenever I ran across ruptured diaphragms.

 

[Richard Cranium]

Since it's in the same vicinity, by chance, did you wrap any teflon tape around the fuel pump rod plug?

 

[miller]

Since your going to pull the fuel pump, anyway, if for nothing else to change the gasket...

Highly recommend while you have it open, pull the actuator rod, and take a look. Make sure there's not much wobble in the rod's bore. Usually fairly close, so shouldn't be much. Look for any cracks around the boss in there. Oil shouldn't hardly get in there, unless some problem. Be sure rod goes back in the same way, to keep the wear pattern.

 

[67GTX440]

I replaced the fuel pump when the car was in the paint shop and would not start, but never removed the fuel pump rod. Maybe I need to add that to the list when doing the fuel pump and check the fuel pump rod plug. The pump, pump gasket, rod and some teflon tape still won't add up to much. I may even throw in a new PCV. I would think the breather cap would clean up, since it is an original chrome part. Is this something normally replaced at some point? I see the push rods sold with the plug. It it normal to replace the plug with the push rod for some reason?

 

[mopar73dge]

replace the pump lines and filter, do the job once and right, the problem there is its a bit hard to tighten those bolts, I always go back and recheck after a run or two. if its only a little seepage than its just the bolt and gasket. Install new factory style bolts also!

 

[miller]

Can't say on the pump rod, since I've never had to replace one. Stock rods I've had just needed minor clean-up. One off my rebuild 440 only needed .0015 cut on one end.
Have been hearing about after-market rods being no good, not right material, or not heat-treated right. So consider where you get one from.

That pump rod plug...only reason it's there is access to get the rod in and out of it's bore.

When you pulled the fuel pump the time you mentioned, was there much oil in there?
Shouldn't be. Everyone I've pulled, pretty much bone dry inside. Rod gets lubed from the top side.

 

[440beep]

This is helpful as I've been chasing an oil leak from the front of the motor also. Already pulled the timing chain cover and gasket was bone dry so no leaking from there. Pulled the oil pan and replaced gasket, and no leak from there.

Somebody else mentioned pulling the fuel pump, and I never realized there was specific bolts for the fuel pump. I forget if we used the special bolts or just "any old" bolt that had fitting threads. Now I'm anxious to pull the fuel pump and see what kind of bolts we used and hoping that might be the problem. Glad to know about the pump rod hole too.

 

[miller]

Those special bolts are easy to spot. About 2" long, but main dif is the heads of the bolts. Built on washers, with smaller hex heads, if you can picture it. Only ones like that on the motor.

Know it's not much, but have never had an oil leak at the fuel pump. Only use light coat of coppercoat on the gasket.

 

[440beep]

Hex heads? You mean that you need an allen head wrench to install them? If so, mine definitely aren't those and if I remember, I use a 1/2" box wrench to tighten them. Mancini Racing has these.....

Those special bolts are easy to spot. About 2" long, but main dif is the heads of the bolts. Built on washers, with smaller hex heads, if you can picture it. Only ones like that on the motor.

Know it's not much, but have never had an oil leak at the fuel pump. Only use light coat of coppercoat on the gasket.

 

[bm02tj]

Before you take it apart clean all around it then run long enough to see the exact spot it is leaking so you know what to fix

 

[miller]

Hex heads? You mean that you need an allen head wrench to install them? If so, mine definitely aren't those and if I remember, I use a 1/2" box wrench to tighten them. Mancini Racing has these.....
View attachment 305403

Yup, hex head. Those are the right bolts. (Allen type are called socket hex)

 

[65-440]

I also put a little sealant on the bolt threads, just so no oil will wick down the bolts ...

 

[Richard Cranium]

I also put a little sealant on the bolt threads, just so no oil will wick down the bolts ...

Good advice, but since this thread is now 8 months old, I sure hope that he's got the problem solved by now.

 

[65-440]

Good advice, but since this thread is now 8 months old, I sure hope that he's got the problem solved by now.

Haha, ooops !