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Topic: What is this? (Read 681 times) previous topic - next topic

What is this?

Can anyone identify the tubing that runs next to the oil filter in the attached picture? In addition to the oil in the photo, oil is venting out the end of the tubing beside the oil pan. My first thought is it looks similar to the PCV system on other engines, but that is just a guess.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: What is this?

Reply #1 –
Are you talking about the two in the foreground or the ones background that have oil all over them.

If there is an open tube that is the crankcase vent.  If you overfill the oil it will throw all of the excess oil out that pipe.  Also if  the rings are going south you will get excess blowby out that tube.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: What is this?

Reply #2 –
I meant the one covered in oil.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: What is this?

Reply #3 –
It look like the vent tube to me.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: What is this?

Reply #4 –
Commonly called a slobber tube.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: What is this?

Reply #5 –
Over the last 8 years, I have periodically had the tube slobber more and then less.  At one time, I thought it was because of the dipstick mis-calibration (do a quick search on the forum).  Started filling to mid-range on the dip stick but last oil change interval (about 4000 miles), I lost 3-4 qts.  This current one, after 4000 miles and filling to the upper line I've only used about 1 qt so I'm confused.  Will continue to monitor.

If it gets to be a problem, some of us have added a catch can or extended the tube lower in the engine compartment.  Helps cut down on any oil dripping into the jet stream and ending up on the toad.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: What is this?

Reply #6 –
Normal crank case vent tube, I've never seen one without oil on it because that's what they do. If it ever puts oil spots on your tow zip tie A 16 oz pop bottle to it with a bit of foam stuffed in the bottom, if the hose fits tight in the opening drill or cut some holes in the top of the plastic bottle. May be tmi for you but may help someone.
Dub McBride 1996 270

Re: What is this?

Reply #7 –
Quote from: Dub –
Normal crank case vent tube, I've never seen one without oil on it because that's what they do. If it ever puts oil spots on your tow zip tie A 16 oz pop bottle to it with a bit of foam stuffed in the bottom, if the hose fits tight in the opening drill or cut some holes in the top of the plastic bottle. May be tmi for you but may help someone.
That sounds like some good old fashioned red neck engineering, except you didn't mention using baling wire or duct tape. Those are usually my go to repair supplies.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: What is this?

Reply #8 –
Short cut for catch can and does the same. Country folks can make a way..
Dub McBride 1996 270

Re: What is this?

Reply #9 –
Quote from: Dub –
Short cut for catch can and does the same. Country folks can make a way..
That sounds like a good topic for a thread. ""Country Folk Fixes"
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: What is this?

Reply #10 –
Quote from: dbennett9 –
That sounds like some good old fashioned red neck engineering, except you didn't mention using baling wire or duct tape. Those are usually my go to repair supplies.


Yup, but it WORKS.  Just make sure the surface area of the holes for the exhaust are larger than the diameter of the OE hose.  You can certainly catch oil vapor, but do NOT restrict air flow.

And, yes, overfilling the crankcase is the #1 cause of excessive oil from the crankcase vent.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: What is this?

Reply #11 –
Back when Detroit introduced the 2 cycles, the slobber tube(s) just dumped the airbox (below the blower) oil on the ground. It was one thing to do on the road but on a boat, it got the bilge dirty. Detroit solved this by installing a catch tank that can be emptied. They also made a drain system with check valves to allow the oil to dump back into the oil pan. Ours has the drain system, others have the catch tank.

The same thing can be done to a 4 cycle on the breather pipe/hose. Care has to be done in the design so it can't be blocked/restricted and build up pressure in the crankcase. Excess pressure will blow oil out the crankshaft seals. High mileage engines will have more blowby and will need to empty the tank more frequently.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: What is this?

Reply #12 –
Any oil that makes it's way into the radiator fins will act like a dust magnet and plug it up fast.
I had that problem in my 1981 Foretravel with a 3208 cat. 
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: What is this?

Reply #13 –
Start by thoroughly cleaning the black grease and oil from the whole area and see where the oil comes from,use water soluble
degreaser and or a air powered syphon gun with mineral spirits,yours looks like its been seeping and leaking for years.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: What is this?

Reply #14 –
You have a C8.3. vent tube is on the other side of the engine. The hose with 2 clamps is the turbocharger oil return line.

1994 U280
Build #4451
"If everyone is thinking alike, then somebody isn't thinking"

Re: What is this?

Reply #15 –
Once upon a time, in a world now mostly gone by, almost all internal combustion engines had a crankcase vent tube and they were equipped with a check valve so air only went out.  We also had a strip of oil and dirt running down the center lane of our roads and highways.  When positive crankcase ventilation, with the slobber re-introduced for be burned, it was amazing how fast the black strip on the road disappeared.  I'm not sure about the Cummins, but my other four vehicles have crankcase breather tubes.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: What is this?

Reply #16 –
I had 2 on my old 6v92.. was a major mess. Of course, there was never any rust.

Re: What is this?

Reply #17 –
Think you should get your serial number and check the Cummins web site and register your engine so you can look at a diagram
of the engine and identyfy the parts,its hard for us to tell you what it exactly is when we don"t know what engine it is,some in that
time frame and a 270 had a 400 hp engine.
96 U270 BUILD 4810
85 380SL
Drummonds TN.