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Oil bath air filter/smoke question

1966BroncoNewbie

New Member
Joined
May 20, 2024
Messages
4
Hi I'm new to the forum. I recently bought a 1966 Bronco that has a 6 cylinder engine with an oil bath air filter and is pretty much original. When driving it recently at higher, 60+ mph speeds, it produced a lot of gray smoke. My friend, who is very mechanical and is helping me with the restoration, thinks it may be caused by oil from the oil bath air filter being sucked into the carburetor at the higher speeds. He is recommending modifying the existing air filter so that it can accommodate a paper air filter. It doesn't smoke at lower speeds, say below 50mph. Any suggestions on what may be causing the smoke? And, would you recommend modifying the air filter to a paper type? Thanks.
 

JB Fab

Sponsor/Vendor
Bronco Guru
Joined
Mar 21, 2004
Messages
1,286
That is easy enough to check.... drive it fast enough to smoke and pull over and see if the inside if the carb is oily.
Or pull the air cleaner off and drive it 60+
It it were mine I would do a compression check, especially if it was sitting for a long time before you bought it?
 

Speedrdr

Contributor
Not so wise OLD owl
Joined
Nov 27, 2017
Messages
1,495
Loc.
Paris, MS
The bigger question here is how do you get an EB with a six cylinder engine over 60mph?
Either (1) a very long section of “flatness”, (2) a steep downhill grade, or (3) incorrect speedo gear in the transfer case.
Had a 200 I6 that replaced the 170 I6 it was born with and I can testify to all of the above methods. Lol

Randy
 
OP
OP
1

1966BroncoNewbie

New Member
Joined
May 20, 2024
Messages
4
That is easy enough to check.... drive it fast enough to smoke and pull over and see if the inside if the carb is oily.
Or pull the air cleaner off and drive it 60+
It it were mine I would do a compression check, especially if it was sitting for a long time before you bought it?
Thanks. We are going to test it without the air cleaner. I’ll discussion the compression check recommendation with my mechanic friend.
 
OP
OP
1

1966BroncoNewbie

New Member
Joined
May 20, 2024
Messages
4
Either (1) a very long section of “flatness”, (2) a steep downhill grade, or (3) incorrect speedo gear in the transfer case.
Had a 200 I6 that replaced the 170 I6 it was born with and I can testify to all of the above methods. Lol

Randy
It was on a freeway bringing it home from having the gaskets replaced.
 
OP
OP
1

1966BroncoNewbie

New Member
Joined
May 20, 2024
Messages
4
Hi I'm new to the forum. I recently bought a 1966 Bronco that has a 6 cylinder engine with an oil bath air filter and is pretty much original. When driving it recently at higher, 60+ mph speeds, it produced a lot of gray smoke. My friend, who is very mechanical and is helping me with the restoration, thinks it may be caused by oil from the oil bath air filter being sucked into the carburetor at the higher speeds. He is recommending modifying the existing air filter so that it can accommodate a paper air filter. It doesn't smoke at lower speeds, say below 50mph. Any suggestions on what may be causing the smoke? And, would you recommend modifying the air filter to a paper type? Thanks.
Removed the oil bath air filter and put a paper air filter on it. Drove it at higher speeds (60 and 65 mph). It didn’t smoke so hopefully smoking issue is solved. But we’ll keep an eye on it.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
48,468
That’s great to hear!
Is it possible that the oil was overfilled? Or that perhaps it was a lower viscosity than recommended?
I’ve seen oil bath air filters, of course, but have never had to live with one. So I don’t know their little ins and outs and characteristics.
How hard was it to convert to paper?
 
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