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smoke coming out of oil breather

nyhillbilly

Full Member
Joined
Sep 22, 2006
Messages
173
Loc.
Canton, MI
ok stupid question, i know some smoke will come out of an oil breather but this is enough to fog up under the hood, is this a sign of

1. coolant in oil ?

2. valve stem seals seeping?

3. piston ring blow by?

4. something else?

5. know any good fixes?


i bought the truck late last summer and havnt ran it unitl today, but even when i bought it there was a heavy residue in the air filter cover. I found a couple other problems too but will start new posts to keep them seperate,, thanks
 

Pokey71

Bronco Guru
Joined
Feb 24, 2007
Messages
1,010
Does one side have a PCV with a hose attached to the air filter or carb?
 
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nyhillbilly

nyhillbilly

Full Member
Joined
Sep 22, 2006
Messages
173
Loc.
Canton, MI
Does one side have a PCV with a hose attached to the air filter or carb?

drivers side has a pcv valve with hose to carb spacer plate, pass side has a breather filter cap with a hose that goes to the bottom of the air filter.

smoke is pouring out of the pass side from between the vavle cover and the breather filter cap, the seal between the two is not that good, but it shouldn't pour out like it is
 

rustbucket

Bronco Guru
Joined
Mar 22, 2004
Messages
1,579
How does the smoke smell? I'm betting on coolant. Drain the oil and see what it looks like before running it again.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
Venting out the breather is either the PCV isn't working correcly or the rings are so worn that the blowby is more then the PCV system can handle.
 
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nyhillbilly

nyhillbilly

Full Member
Joined
Sep 22, 2006
Messages
173
Loc.
Canton, MI
How does the smoke smell? I'm betting on coolant. Drain the oil and see what it looks like before running it again.

the smoke was in the cab as well when i took it for a ride, because i have not plugged the holes in the firewall yet, and it really didn't have a smell, at least not a strong one, very faint oil smell, definetly not a burnt or heavy oil smell. also it was only running for 15 minutes and about 1 mile down the road and the temp was 210 degrees with it 40 degrees out today, and it didn't really go down when i was driving versus stopped
 
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nyhillbilly

nyhillbilly

Full Member
Joined
Sep 22, 2006
Messages
173
Loc.
Canton, MI
pcv was brand new, i blew into it, checks ok. i took off the aircleaner which i cleaned out the top and bottom and replaced the filter, and after i checked it today it already had a dark grey slime coating the bottom, it wasnt just oil felt like oil water mixture,

I will take the motor out this week and break it down to take a look, anyone know a good machine shop on the west side of Detroit????
 
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nyhillbilly

nyhillbilly

Full Member
Joined
Sep 22, 2006
Messages
173
Loc.
Canton, MI
updated, some good news i guess

I took the intake off, and no signs of coolant, took the spark plugs out and #3 was caked in oil/ carbon, took the head off and the chamber was also coated heavily in oil residue and the the valves were both black with the same residue, the rest of the chambers had one black dry valve and one orangeish white valve. I am assuming from this that i have a bad piston ring.

Bores still show honing cross thatch, and pistons are .030" forged.


You guys think just a rering and bearing kit i will be ok?
 

badmuttstang

redneck grease monkey
Joined
Oct 25, 2009
Messages
2,807
Definitely bad rings from the sound of it if there is no lip at the top of the cylinder and no scoring then ball hone to freshen up cylinders and re-ring hard to say though without seeing
 
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