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Topic: small leak from hose attached to tank at rear of engine (Read 898 times) previous topic - next topic

small leak from hose attached to tank at rear of engine

Not sure which tank it actually is, but on my u320 with the M11 I have a small leak from a hose at the bottom of the large black tank located at the left rear side of the engine (right behind the U320 label on the outside cover) There are two hoses coming from the bottom of the tank and the right one is leaking. Doing the "taste" test of the fluid on the ground, it appears to be MAYBE hydraulic(??) fluid not engine oil.
Is this just a matter of tightening up the hose or am I looking at something major. Also the question is, is it safe to drive with the little leak I have noticed?
What is the tank for?
Advice whould be appreciated. Sorry could not provide pictures right now as the coach is parrked baked right up against a fence in my RV parkjng space.
Peter
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #1
Hydraulic reservoir, Peter. The oil in there is the same as engine oil.  If the hose is leaking it needs to get fixed.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: small leak from hose attached to tank at rear of engine

Reply #2
It looks like it is leaking right from the attachment to the tank not the hose. Hopefully just a turn to tighten?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #3
Absolutely try tightening it first, using two properly sized wrenches, one on the tank fitting and one on the hose fitting. It could also be the threaded fitting in the tank or a failed crimped fitting on the hose which will require replacing the hose.
Try the simple stuff first, good luck. 👍
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: small leak from hose attached to tank at rear of engine

Reply #4
If you need to add any fluid, verify what is in that tank. It could be oil, hydraulic fluid, ATF........
Alan Fink
Waupun, WI
2000 Blue Bird Wanderlodge  LX40
2018 F150 4x4
2020 Jeep Wrangler Unlimited  Rubicon JL

Re: small leak from hose attached to tank at rear of engine

Reply #5
If it's a black tall round tank on the left it is the hydraulic oil tank, holds oil used for power steering and hydraulic cooling fans. Delo oil is fine.
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: small leak from hose attached to tank at rear of engine

Reply #6
HDFF
Yes that is the tank. I am going to attempt to tighten the one fitting and hope that is the issue. Hopefully
I do not have to replace a hose as I think that is beyond my capability as I do not have the place to put the fluids or the tech stuff about replacing it or such... 
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #7
I am going to attempt to tighten the one fitting and hope that is the issue.
I hope you find the connection loose, and tightening it solves your problem.

The hoses used in the Foretravel hydraulic system are typically fitted with JIC 37 degree flare connections.  The seal is achieved through metal-to-metal contact between the finished surface of the male fitting nose and the inside diameter of the female flare connector.  The threaded portion of the fitting simply holds the two sealing surfaces together.  You should not use any type of thread sealant on JIC connections.

JIC fitting - Wikipedia


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: small leak from hose attached to tank at rear of engine

Reply #8
Do you know exactly where it is leaking. Clean the area with brake clean to find the exact location. Hopefully
it is the JIC fitting is loose and do what Chuck says. If it is the pipe threads that are leaking they can't be
turned much with out draining the oil and removing the JIC fittings. If that is the case take the fitting apart
and apply a good pipe dope and Teflon tape over the pipe dope. Pipe dope by its self is ok but I never
trust Teflon tape by its self. Those are the pipe threads I mean.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: small leak from hose attached to tank at rear of engine

Reply #9
If I have to take the fitting off to re seal with pipe dope ( I have Rectorseal Tru-Blu...hope that is ok)  do I just carefully remove the fitting and let the fluid drain into a pan?  Can I re  use the fluid and just top up?  How much does the canister hold??    Sorry...all amateur questions..

Also from experience does anyone know the wrench size required to remove the fitting.? It definitely is larger than any wrenches I have and I will have to borrow or purchase one
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #10
If you can keep the oil clean it can be put back into the tank. The fitting size is 1 3/4" borrow a 20" crescent no reason to buy a wrench that size. I don't think that will be your leak though. If it is you will have to clock it and the 90 to align with the hose.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: small leak from hose attached to tank at rear of engine

Reply #11
First make sure where the leak is. If the filters haven't been change in a while it would be a good
time to change them and just add new oil. It probably hold at least 3 gallons but I am not sure
I have changed the filters and oil in the Monaco I owned. It had the same filter canaster.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: small leak from hose attached to tank at rear of engine

Reply #12
Ok perfect info all...being this tank by the looks does not have a fluid level indicator how do you tell how much oil to add?

Also being in Canada geese  that type of oil is hard to find...
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #13
Ok perfect info all...being this tank by the looks does not have a fluid level indicator how do you tell how much oil to add?

Also being in Canada geese  that type of oil is hard to find...

There is dip stick in the lid.

If, like most Fortravels is uses Delo 400 15-40, should not be hard to find. I guess Shell Rotella T 15-40 could also be used if you can't find the Delo.
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: small leak from hose attached to tank at rear of engine

Reply #14
...how do you tell how much oil to add?
See photos of the dip stick in thread linked below:

1996 hydraulic tank dip stick won't tighten
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: small leak from hose attached to tank at rear of engine

Reply #15
Thanks again. I presume I measure the fluid level when warm.  Maybe there is cold and hot level
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #16
I think there is a hot and cold level.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: small leak from hose attached to tank at rear of engine

Reply #17
So good news and thanks to all.... just a slight tightening of the right hose at the canister stopped the leak.  Or at least that is the impression I have after running it for about a half hour. The fluid was just a tad below the full at hot level so I left it alone.

PS. Crescent wrench would not work as the head was too big to fit in between the hoses. I eventually had to buy a 1 3/4 wrench which slipped in well.
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #18
Quick note
I thought everything was well with my fix but seems to be seeping again. Does anyone know a figure as to how much to replace these two hydraulic hoses?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: small leak from hose attached to tank at rear of engine

Reply #19
Not in your area but if there are any oilfield supply stores around they will know where you can get hoses made,get swivel ends
on both ends,will be easier to install.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: small leak from hose attached to tank at rear of engine

Reply #20
Are both hoses really bad? Neither hose is under real pressure-- one the return line from fan motors/power steering gear and the other to the suction side of the hydraulic pump.

Have you identified the actual source of the leak? Hose or fitting?
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: small leak from hose attached to tank at rear of engine

Reply #21
On the hydraulic hoses, the ends can be reused and just outside of Edmonton there
is Newline hose & fittings or in Edmonton there is Greenline both of those companies
will have the hose.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport