excessive oil out of block breather

Engine, Transmission and related drivetrain.
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excessive oil out of block breather

Postby Dimes4Life » 18 Apr 2016 19:50

Today while I was driving on freeway..I smelled burning oil and saw smoke coming from tranny shifter hole..drove home jacked it up. Didn't see and puddles block & tranny were relatively dry but I did see a burned hole in the hose connected to the block breather tube...looks like either header burned a hole in hose or excessively hot oil is shooting out onto header. i ran this hose for 2 yrs & never had heat ussue although it was a heater hose connected..found a place here in bay area that supplies 1/2 inch fuel line and other huge size hoses
My question is that I thought only vapor came out this breather tube..if header burned hole...ill look for relacement hose and heat proof tape. But why would oil start shooting out in first place?
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Re: excessive oil out of block breather

Postby SteveEdmonton » 18 Apr 2016 20:02

Looks to me like the hose has had several "close encounters" with a hot header, judging by the melt marks close by to the gaping hole.

Was the hose actually connected at both ends, or did one end maybe work free and then flop down onto the header? From your photo it looks like a properly connected hose "should" have enough clearance to avoid melting like that.

And you're right about the purpose of this line: the steel vent-pipe attached to the block simply vents vapours from the crankcase into your PCV valve. In the photo with the circles, that valve seems to be in an odd place. It's been a long time since I had a stock carb / manifold setup though so maybe it's normal. In any case, I don't think it's plausible that hot oil was inside that rubber hose. And even if it was, I don't think it's plausible that it would have melted that hose.

So again, is it possible that this hose contacted your header? Are there any traces of melted hose on the header that might point in this direction?

G'luck! :)
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Re: excessive oil out of block breather

Postby two_68_510s » 18 Apr 2016 20:04

What Steve said ^^^^^That sure looks like the header burned it, you have areas that are charred from the outside, my dear Watson!

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Re: excessive oil out of block breater

Postby Dimes4Life » 18 Apr 2016 21:28

Thanx for response..the hose did touch the header...all the vibration made it ease off the vent pipe and rub on
the header. I replaced the hose and made sure it doesnt touch anymore...will test again tomorrow.
BTW..I. couldn't find any burned rubber or residue on the header. The semi-circle shape looked like header melt.

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Re: excessive oil out of block breather

Postby okayfine » 19 Apr 2016 06:03

Hose clamps. Get some.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson

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Re: excessive oil out of block breather

Postby datzenmike » 20 Apr 2016 16:37

Find a hose that is petroleum resistant. Oil and gas dissolves real rubber.
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