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Topic: Slobber Tube Catch Can (Read 1801 times) previous topic - next topic

Slobber Tube Catch Can

Last fall I mounted a can/ rubber hose/ two hose clamps/ steel wool/ and one 5/16-18 bolt & shake proof nut on the "slobber" tube on our 8.2 DD engine. Last nite I took it off to check how it was doing. Turns out the steel wool was wet with oil residue and, after pulling the wool out, there was almost 3/4" of what looked like water in the can. Now where did THAT come from? Condensation?

This liquid has convinced me to go the 1" ID hose out the back end! Then I can quit worrying about the water can affecting the engine.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Slobber Tube Catch Can

Reply #1 –
Quote from: nitehawk –
Condensation?
That would be my guess.  Hot moist air from engine venting out the tube into a cold can - perfect conditions for condensation in the can.

I put one of those catch cans on our coach 'bout a year ago - made it out of a aluminum welding rod container - guess I need to check ours!
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Slobber Tube Catch Can

Reply #2 –
Condensation or road splash depending on where the can is located.

And, it would take VERY little water to get your attention, as it would never evaporate because of the oil on top of it.  Very normal.
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: Slobber Tube Catch Can

Reply #3 –
Not road splash in our case, as we do NOT drive in the rain if at all possible.
I wonder if putting a 1/8" diameter hole at the low point in the slobber can would let the condensate drip out? It would be covered with the steel wool and yet let moisture seep thru. Might be better for those of us that "forget" to check.
This way we would help communities maintain their roads by oiling them. It would also contribute to preventing burnouts and squealing tires. >:D  >:D
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Slobber Tube Catch Can

Reply #4 –
Why are you putting a can there? Does it help anything?
Rick Barna
St. Petersburg FL.
1998 U270 36'
Build # 5232
1972 CJ 5 Jeep

Re: Slobber Tube Catch Can

Reply #5 –
Quote from: barndog –
Why are you putting a can there? Does it help anything?
Rick,

Some members believe putting a catch can on the crankcase vent tube reduces the amount of oil residue that builds up on your towd.  I have had one on our coach for a couple years, and don't really notice much difference in the "dirtiness" of our towd.  Unless you run your engine oil level too high, you shouldn't get much oil out the vent tube.  I think most of the trash on our towd comes from road grime, oil and other fluids thrown up by the tires, exhaust pipe emissions, and "stuff" blowing out the purge valve of our air dryer.  Others may have different thoughts...
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Slobber Tube Catch Can

Reply #6 –
Excess blowby from the crankcase vent is an indication of engine wear. If you are seeing oil on your toad find out why sooner than later.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Slobber Tube Catch Can

Reply #7 –
I have the 8.3 cummins 12 valve engine,my vent tube runs down the engine to near give or take where the oil pan gasket is.

Now think for a moment,it would take a whole lotta air and wind to get oil from the end of that tube to your toad vehicle
under normal circumstances.If you have oil from the tube getting on your toad you have a problem of excessive blowby.

96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Slobber Tube Catch Can

Reply #8 –
Catch cans are mostly done on coaches that have rear radiators.
The selected media item is not currently available.Bill&Doris 97 U270 36'
University of Parris Island Class of 66
Semper Fi  Build# 5174 MC#17094

Re: Slobber Tube Catch Can

Reply #9 –
When I built my catch can made of pvc I also added a ball valve on the bottom. I drain it about every 10,000 miles. ^.^d
Bill
Wild Bill Colston
1997 Class A Towing 2016 ford F150 XLT extended cab with Golf cart in 8 ft bed or a 2004 Jeep Grand Cherokee
Retired Aircraft Maint Tech A&P Line Crew Chief
Pilots lisc--------Commercial and Multi Eng

Re: Slobber Tube Catch Can

Reply #10 –
Quote
Unless you run your engine oil level too high, you shouldn't get much oil out the vent tube.
I put one on this rig before our trip. The 8.3 uses some oil and I wanted to make sure that it was not overfilled. After about 1,800 miles there's just a bit of residue on the bottom of the can. On another rig, I also used one to determine proper calibration of the dipstick. Turned out it was off by quite a bit.
jor
93 225
95 300
97 270
99 320

Re: Slobber Tube Catch Can

Reply #11 –
The catch can's main function is to capture any--ANY-- oil that comes out and that may be sucked up into the engine fan and then blown into my rear--REAR---radiator. Oil in the REAR radiator will cause dirt to stick to the fins of the radiator and hence higher temps when the radiator air flow thru is restricted.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Slobber Tube Catch Can

Reply #12 –
My 6/92has a factory one that Foretravel must have put on, 92series motors have vents on the side of the blocks and any oil that comes out of those vents is pushed out into solbertubes and is sent down to a catch can underneath the rear cross member. The older natural motors pre sliver 92's leaked oil like a sieve if left under a 1'000 RPMs.at idle.
Andy & Eileen
MONTROSE COLORADO
1992 U300  40' 6V92 TA
2016 4 Runner
1998 Jeep Grand cherokee

1998 Jeep Grand Cherokee) Build # 4135 Skp# 122921

Re: Slobber Tube Catch Can

Reply #13 –
I have a Dwyer digital manometer we used to check crankcase pressures with.Think I will get some specs and check pressure.
Am curious to see if the engines that have alot of "slobber" have higher pressure.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Slobber Tube Catch Can

Reply #14 –
#1 cause of excessive oil in crankcase breather hose is overfilling the crankcase.  Too much oil and it gets blown out!

Calibrating the engine oil dipstick will solve the vast majority of "oil consumption" issues in RV's.
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