Oil Blow-by in the Air cleaner

fumann

Joined

Nov 26, 2005

Threads

22

Messages

520

Location

Phoenix, AZ

• Sep 14, 2006

• #1

I've got a 77 FJ40 with original 2F motor. I've not had much road experience with it but now that I'm driving it occasionally, I'm seeing oil in the air cleaner, apparently coming from the vent tube on the valve cover.
Any ideas of how to deal with it?

Thanks in advance for your help!

 

jcj_78FJ40

Joined

Apr 7, 2005

Threads

53

Messages

1,345

Location

Afton VA

• Sep 14, 2006

• #2

fumann said:

I've got a 77 FJ40 with original 2F motor. I've not had much road experience with it but now that I'm driving it occasionally, I'm seeing oil in the air cleaner, apparently coming from the vent tube on the valve cover.
Any ideas of how to deal with it?

Thanks in advance for your help!

Click to expand...

Make sure that the PVC valve, hoses and fittings are not clogged up. Also check to see if you have to much oil in the crankcase.

Good luck

 

grant5127

Joined

Oct 31, 2003

Threads

69

Messages

5,010

Location

Meridian,TEXAS

• Sep 14, 2006

• #3

Blow-by.....compresson leaking past the piston rings.......do a leak down test

 

fumann

Joined

Nov 26, 2005

Threads

22

Messages

520

Location

Phoenix, AZ

• Sep 14, 2006

• Thread starter
• #4

I have a new PVC installed. Just got the oil changed, so I guess
we'll see if the problem persists.

Thanks,

 

cruiser88

Joined

Feb 21, 2006

Threads

296

Messages

11,967

Location

Winston Oregon

• Sep 14, 2006

• #5

blow by

 

jcj_78FJ40

Joined

Apr 7, 2005

Threads

53

Messages

1,345

Location

Afton VA

• Sep 14, 2006

• #6

Check the simple stuff first.

Take another look at the PVC hose and the manifold fitting to make sure that they are not clogged up. If it is, it will throw oil into the air filter.

If it’s not clogged, then unfortunately it’s probably blow-by.

 

fumann

Joined

Nov 26, 2005

Threads

22

Messages

520

Location

Phoenix, AZ

• Sep 14, 2006

• Thread starter
• #7

jcj_78FJ40 said:

Check the simple stuff first.

Take another look at the PVC hose and the manifold fitting to make sure that they are not clogged up. If it is, it will throw oil into the air filter.

If it’s not clogged, then unfortunately it’s probably blow-by.

Click to expand...

Thanks, I think I understand what is happening now. I found a good explanation of the problem here. http://www.misterfixit.com/blow-by.htm. Unfortunately, it looks like bad news for the 2F, which wasn't running bad and not smoking, or buring oil, as far as I could tell, so I hardly expected that the rings were shot. I'll take a closer look this weekend before I throw out the 2F with the bath water er ...bath oil.

It developed another problem last week, the throw-out bearing is squealing, another reason to have to pull the motor. I had planned to drop a 350 Chevy in it anyway,
all of this just accelerates the timing of that.

Thanks,

 

ecodan

Joined

Sep 9, 2006

Threads

18

Messages

113

Location

Perth, Western Australia

• Sep 28, 2006

• #8

I have a similar problem,
anyone made a cannister or device to trap the oil without removing the hose completely from the air cleaner (i dont like the idea of dropping it on the road or into the chasis rail). Meanwhile im going to change my vacuum hose (currently a new heater hose) as i think its collapsing under load and therefore rendering the pcv valve usless.

 

Last edited: Sep 28, 2006

Texx

Joined

Feb 27, 2002

Threads

168

Messages

2,891

• Sep 28, 2006

• #9

It could be as minor as a valve problem...you could pull the head and do an in frame overhaul for alot less hassle than a V8 swap. Compression test and cylinder leak down test will tell you which way to go.

 

JohnnyC

Long ago TLCA# 2231

Joined

Jun 17, 2005

Threads

300

Messages

18,030

Location

UpState Ny, Wells Me

• Sep 28, 2006

• #10

I’ve had a problem with the oil going into the air cleaner also...big time blow-by my truck also has over 430,000 miles on it. The quick fix is to disconnect the PVC breather hose that goes into the air cleaner and get a much longer one and vent it down next to the frame (droping it to the road as they say). This will buy you some time. I have been running my truck this way for the past 13+ years...over 200,000+ miles. No more oil in the air cleaner...and no more fouling plugs...no more smoke. Works for me. Not the best for the environment or my driveway

 

65swb45

Elder Statesman

Supporting Vendor

Joined

Apr 14, 2004

Threads

1,474

Messages

36,866

Location

818-953-9230

Website

www.marksoffroad.net

• Sep 28, 2006

• #11

ecodan said:

I have a similar problem,
anyone made a cannister or device to trap the oil without removing the hose completely from the air cleaner (i dont like the idea of dropping it on the road or into the chasis rail). Meanwhile im going to change my vacuum hose (currently a new heater hose) as i think its collapsing under load and therefore rendering the pcv valve usless.

Click to expand...

On my 45 [which has the PCV on a side passage of the oil filler tube] my simple 'fix' for the blowby problem, which bought me almost two more years of driving time, was to put a piece of fine mesh window screen, doubled over, against the passageway to the PCV valve. This trapped the vast majority of the oil BEFORE it could get to AND THROUGH the valve.

I have also seen a twin hose setup between the valve cover and air cleaner, with the two hoses plumbed into and out of a gallon detergent bottle with a rag stuck in it. 'IN' hose stuffed to the bottom of the bottle, where the rag is. 'OUT' hose closer to the top, and hopefully far enough away from the oil mist! Booty fab fo sho, but worked pretty well from what I could tell.

Best

Mark A.

 

grant5127

Joined

Oct 31, 2003

Threads

69

Messages

5,010

Location

Meridian,TEXAS

• Sep 28, 2006

• #12

Many people I know believe in" molybdenum disulfide" additives.. and they work for the most part.. depends on the over all motor condition ... example here--- http://www.bobistheoilguy.com/blowby.html believe it or not... I've seen it work.....