Oil Pouring Out of Air Cleaner

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CharlieB
Posts: 234
Joined: Sat Aug 22, 2015 8:01 pm
Your car is a: 1976 Fiat Spider

Oil Pouring Out of Air Cleaner

Postby CharlieB » Thu Apr 26, 2018 1:27 pm

Just took my '76 124 for a test drive and oil is pouring out of the air cleaner housing. Oil is coming up through the carburetor somehow.
I know I've seen this mentioned on the forum somewhere, but I can't find it.
Anyone know what causes this?
Thanks,
CB
1976 Fiat 124 Spider

Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: Oil Pouring Out of Air Cleaner

Postby Nut124 » Thu Apr 26, 2018 1:33 pm

It's coming from the crank case via the breather tube.

One or more of the below is the cause:
- Oil level too high
- Too much blow by - worn rings
- Too much speed in the corners for an old pan design

CharlieB
Posts: 234
Joined: Sat Aug 22, 2015 8:01 pm
Your car is a: 1976 Fiat Spider

Re: Oil Pouring Out of Air Cleaner

Postby CharlieB » Thu Apr 26, 2018 1:38 pm

That was my first thought too, but it's actually coming up through the carb itself. Vent hose is clean.

Edit: I'll check oil level, I didn't think about that.
Thanks
1976 Fiat 124 Spider

CharlieB
Posts: 234
Joined: Sat Aug 22, 2015 8:01 pm
Your car is a: 1976 Fiat Spider

Re: Oil Pouring Out of Air Cleaner

Postby CharlieB » Mon Apr 30, 2018 2:19 pm

Well I checked the oil level and it is normal.
I did confirm that the oil is coming through the carb and not the hose.
I guess a compression test would be the next logical step...correct?
1976 Fiat 124 Spider

User avatar
Odoyle
Posts: 440
Joined: Mon Dec 01, 2014 10:06 pm
Your car is a: 1983 Pinafarina Spider
Location: CA

Re: Oil Pouring Out of Air Cleaner

Postby Odoyle » Mon Apr 30, 2018 3:05 pm

Yes, take compression test and record numbers, you can rent a comp. tester from Autozone.

Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: Oil Pouring Out of Air Cleaner

Postby Nut124 » Mon Apr 30, 2018 5:04 pm

I cannot figure out how oild could be coming from the carb if not the breather hose. What kind of carbs?

EGR system? Does your car have one?

If you have IDFs or other individual runner carbs, then the following scenario is plausible:

At idle or low RPM there could be flow reversal due to long duration cam and header back pressure. This can cause a column of gas vapor to push back into the air cleaner. If your intake valve seals are work out, oil could be drawn into the vapor column and end up being deposited inside the cleaners. A hot cam with an unsuitable header can do this, but only with single runner intakes like with IDFs.

CharlieB
Posts: 234
Joined: Sat Aug 22, 2015 8:01 pm
Your car is a: 1976 Fiat Spider

Re: Oil Pouring Out of Air Cleaner

Postby CharlieB » Mon Apr 30, 2018 8:03 pm

Man I can't figure out how oil could be coming up through the carb either.
I have a single carb (Weber 32 ADFA).
For what it's worth, the valve seals were replaced about 1,000 miles ago when I did a head gasket replacement.
I ran the car at idle until it got up to temperature and didn't notice any oil coming out.
I'll test compression tomorrow.
Thanks for the responses.
Edit: No, I do not have an EGR system.
1976 Fiat 124 Spider

CharlieB
Posts: 234
Joined: Sat Aug 22, 2015 8:01 pm
Your car is a: 1976 Fiat Spider

Re: Oil Pouring Out of Air Cleaner

Postby CharlieB » Tue May 08, 2018 2:28 pm

Well, Nut124, I think you were right. I decided to drain the oil and noticed I had a little less than a quart too much.
Not sure how I did that but...mystery solved.
I am still confused about the fact that oil did not come up through the breather but through the carb instead.
I have driven it about 20 miles or so with the correct oil level and everything is back to normal.
Thanks for the advice
1976 Fiat 124 Spider


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