Weird oil leak coming from fuel pump???

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MopaR&D

MopaR&D

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I have a noticeable oil leak on the front pass. side of my 360 that seems to be getting steadily worse. At first I though it was coming from the dipstick but lately after going on a drive and parking the car I notice oil on the top of the mechanical fuel pump and an occasional air bubble coming out where the bottom stamped section is crimped around the top cast part. I put this pump in less than a year ago, it's a stock replacement from O'Reilly's could it be I got a bad part? And if so is there a way to fix it or do I need another one?
 
excessive crankcase pressure without adequate venting can cause that, but usually it will pop the dipstick out first.
 
mderoy340 said:
Get a new one.
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Dang well at least it was only $18. I'll get a better one off RockAuto.com, damn O'Reilly's letting me down yet again :wack:

73AbodEE I do get pretty high crankcase pressures when I'm flooring it all-out but I have a full PCV system and a breather on one side. I think the breather is restrictive though I feel backpressure when I blow on it with my mouth (insert dirty joke #-o tee hee).
 
A RockAuto pump is likely to be the same quality level so keep an eye on the new one, or buy a better one. Look at Mancini's and others.
 
Funny how a 50 year old factory pump that was on my 64 Belvedere was still good.The quality of replacement parts are so bad now,I feel for the working mechanic trying to make a living dealing with come backs because of replacement parts.A friend put 3 water pumps on in 3 months for a young girls VW Jetta.Now of course she has no idea about bad "Part Store"parts,,only that the mechanic wasn't doing it right.
 
Go on ebay, and get an NOS Carter. Ive picked a few up here and there, for a fair price.

Or you can by a fuel pump from mancini and get out your gold card.
 
jdsduster said:
it may just be the gasket
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If it was the gasket how could the oil make it up to the top of the pump assembly? That may be part of the problem but there is definitely oil seeping out between the upper and lower sections of the pump; like I said before after driving and parking the car I see an occasional tiny air bubble coming out from the 'crimped' area. I'm overseas right now but when I get back I will double-check the gasket and make sure the bolts are on tight.

I'm looking on Summit right now and big surprise (sarcasm) there are stock-type replacement pumps for around $20 then the Edelbrock and Holley HP units for $150+ and nothing in between. I've had good luck with Airtex brand parts I may just get one of those for the time being and then upgrade to an electric pump later. I'd rather not dump lots of money on another mechanical pump as I eventually need to upgrade the whole fuel system to 3/8" line anyway (currently have stock 5/16" lines).

It does piss me off about replacement parts being junk the old pump I had was reused from the stock 318 my car had and worked fine for the 8+ years it was in service. I think all that made it fail was the ethanol-laced modern gas eating away the internal diaphragm.
 
R&R gasket first. Oil, like water and electricity, will take the path of least resistance. Personally, I would try gasket.
 
Not me. If you saw bubbles the pump is bad. Replace it. I only use the Carters myself. Mancini, SUmmit, etc have them.
 
moper said:
Not me. If you saw bubbles the pump is bad. Replace it. I only use the Carters myself. Mancini, SUmmit, etc have them.
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From the OP
I think all that made it fail was the ethanol-laced modern gas eating away the internal diaphragm.

The ethanol sucks. If you have a pressure gauge I'd bet the pressure is also fluxing.
 
moper said:
Not me. If you saw bubbles the pump is bad. Replace it. I only use the Carters myself. Mancini, SUmmit, etc have them.
Click to expand...

Do these include the "regular" stock replacement ones or just the HP ones?

Also I looked at the specs on the HP pumps (any brand) and they all have 1/4" NPT fittings, what size fuel line does that equate to?
 
MOPEkidD-3 said:
Do these include the "regular" stock replacement ones or just the HP ones?

Also I looked at the specs on the HP pumps (any brand) and they all have 1/4" NPT fittings, what size fuel line does that equate to?
Click to expand...

About a split between 5/16"-3/8" , Khalil... I am using a Carter M6270 mechanical pump, with no regulator, 8 A.N. (7/16 " I'd) . it hits at 7 psi, with the bigger diameter line.Advertising is "120 gallons per hour@ 7.5-8.5 psi" 1/4 NPT, ran three of these ( at California elevated) , never had a problem..
 
Abodybomber said:
About a split between 5/16"-3/8" , Khalil... I am using a Carter M6270 mechanical pump, with no regulator, 8 A.N. (7/16 " I'd) . it hits at 7 psi, with the bigger diameter line.Advertising is "120 gallons per hour@ 7.5-8.5 psi" 1/4 NPT, ran three of these ( at California elevated) , never had a problem..
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Thanks for the info Tim...

About the new vs. NOS pumps i'm gonna give one of the NOS ones a try, at ~$30 i think it's worth a shot. My only concern would be ethanol corrosion on that old rubber but i now run Lucas Ethanol Conditioner in my tank after every fillup which is supposed to negate those corrosive effects. Gives a bit more power and MPG too i've found.
 
I'd be checking my oil also, for gas smell. If gas has leaked into the crankcase, change the oil!
 
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