Fuel in oil

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archiethe3rd
Posts: 31
Joined: Mon Mar 04, 2013 7:16 am
Your car is a: 1978 Fiat Spider
Location: Kansas City, MO

Fuel in oil

Postby archiethe3rd » Sat May 13, 2017 5:35 pm

I'm experiencing fuel in my oil on my 78. After sitting most of the winter, I started it a couple weeks ago. It was hard starting, but then went to idle around 2000 rpm and was putting out a lot of white exhaust. I shut it off and noticed a good amount of fluid leaking from the air cleaner housing. I removed the top and cleaned out the residual fluid. It smelled like gas. Later, with the air cleaner top off I tried starting it again. It fired up, went to fast idle then died and shot a spray of fuel out of the carb. It ran for 10 sec. or less. Today I pulled the dipstick, wiped the dirty oil off and smelled the oil. It smelled like gas. I decided to change the oil. When I drained it I got 5 qts of oil and gas mixture out of it. I replaced the mechanical fuel pump 2 years ago. Is there a bad gasket that is allowing fuel in to the crankcase? Any help is much appreciated.
78 Fiat Spider
2014 Ram ProMaster 1500 Cargo Van (the small one)
2014 Honda CRV

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So Cal Mark
Posts: 13839
Joined: Wed Jan 25, 2006 3:45 pm
Your car is a: Fiat
Location: upland, ca.

Re: Fuel in oil

Postby So Cal Mark » Sat May 13, 2017 6:07 pm

a gasket won't cause that trouble. Either the fuel pump diaphragm is leaking or the carb is flooding and pouring fuel into the cylinders.
Mark Allison
allisonsautomotive.com Fiat and Alfa Romeo parts and service. Performance parts our specialty!
Headers, ignitions, wheels, cams, flywheels
starsmark@hotmail.com 909-981-3566

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chrisg
Posts: 746
Joined: Sun Jun 04, 2006 7:30 am
Your car is a: 1971 FIAT

Re: Fuel in oil

Postby chrisg » Sat May 13, 2017 7:50 pm

Ethanol laced fuel and mechanical fuel pumps don't get along well..:especially when left alone together for a while
Chris Granju
Knoxville, TN
'71 FIAT 124BS (pretty), '72 FIAT 124BC,'76 FIAT 128 Wagon(ratbeast), '85 Bertone X 1/9, '70 124BC (project), 79 X1/9 (hot rod in rehab), '73 124BS (2L, mean), '74 124 Special TC, '73 124CS, '73 124 Familiare

archiethe3rd
Posts: 31
Joined: Mon Mar 04, 2013 7:16 am
Your car is a: 1978 Fiat Spider
Location: Kansas City, MO

Re: Fuel in oil

Postby archiethe3rd » Sat May 13, 2017 8:21 pm

Thanks Mark and Chris. Initially when my oil smelled like gas, I freaked (in my head). Couldn't figure out how gas would be in my oil, usually worried about frothy oil. I think it's new fuel pump time.
78 Fiat Spider
2014 Ram ProMaster 1500 Cargo Van (the small one)
2014 Honda CRV

User avatar
So Cal Mark
Posts: 13839
Joined: Wed Jan 25, 2006 3:45 pm
Your car is a: Fiat
Location: upland, ca.

Re: Fuel in oil

Postby So Cal Mark » Sat May 13, 2017 8:33 pm

the danger is that the fuel will displace oil on the bearings and camshaft :(
Mark Allison
allisonsautomotive.com Fiat and Alfa Romeo parts and service. Performance parts our specialty!
Headers, ignitions, wheels, cams, flywheels
starsmark@hotmail.com 909-981-3566

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chrisg
Posts: 746
Joined: Sun Jun 04, 2006 7:30 am
Your car is a: 1971 FIAT

Re: Fuel in oil

Postby chrisg » Sat May 13, 2017 9:33 pm

I had two blow on me in the last year or so. Ultimately, I prefer electric FPs anyway, so it was probably the universe's way of hitting me upside the head for being lazy not going and changing them...but, indeed, gone unchecked you could do some real damage & I gather rather quickly. One of mine showed no running problems, but was leaking into the crankcase. The other was kind enough to make a mess outside the car thus announcing the failure clearly. had it happen on other types of cars in the past but usually associated with obvious fuel pump problems.
Chris Granju
Knoxville, TN
'71 FIAT 124BS (pretty), '72 FIAT 124BC,'76 FIAT 128 Wagon(ratbeast), '85 Bertone X 1/9, '70 124BC (project), 79 X1/9 (hot rod in rehab), '73 124BS (2L, mean), '74 124 Special TC, '73 124CS, '73 124 Familiare

archiethe3rd
Posts: 31
Joined: Mon Mar 04, 2013 7:16 am
Your car is a: 1978 Fiat Spider
Location: Kansas City, MO

Re: Fuel in oil

Postby archiethe3rd » Sat May 13, 2017 10:24 pm

I replaced what I believe was the original mechanical pump. The new one looked about the same but I found out, through help in this forum, that the in and out were opposite the original and how to check that. Are the new mechanical pumps junk? You can find them for $28. I never used any fuel that stated it had ethanol and only put in premium.
78 Fiat Spider
2014 Ram ProMaster 1500 Cargo Van (the small one)
2014 Honda CRV

User avatar
chrisg
Posts: 746
Joined: Sun Jun 04, 2006 7:30 am
Your car is a: 1971 FIAT

Re: Fuel in oil

Postby chrisg » Sat May 13, 2017 11:57 pm

I'm envious of wherever you live. 100% gasoline is available but not terribly common here in TN.
Chris Granju
Knoxville, TN
'71 FIAT 124BS (pretty), '72 FIAT 124BC,'76 FIAT 128 Wagon(ratbeast), '85 Bertone X 1/9, '70 124BC (project), 79 X1/9 (hot rod in rehab), '73 124BS (2L, mean), '74 124 Special TC, '73 124CS, '73 124 Familiare


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