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Topic: Hydraulic Oil is milky amber in appearance  (Read 488 times) previous topic - next topic

Hydraulic Oil is milky amber in appearance

Yesterday I noticed the hydraulic oil has a milky amber appearance. In the spring of this year I had changed the steering gear box along with the hydraulic oil and filters.

I thought it might be entrapped very small air bubbles, but leaving a small sample sit overnight did not change the appearance.

The engine oil and transmission dipsticks look fine.

How could water get in the hydraulic system?
2003 U320 4010 - SOLD
2014 RAM 1500 Ecodiesel

Re: Hydraulic Oil is milky amber in appearance

Reply #1 –
Has anything been pressure washed?

Re: Hydraulic Oil is milky amber in appearance

Reply #2 –
No pressure washing.
2003 U320 4010 - SOLD
2014 RAM 1500 Ecodiesel

Re: Hydraulic Oil is milky amber in appearance

Reply #3 –
This is a new occurrence correct, it was okay last month? Very strange. Guess you could get analyzed to help locate the source. Water would also separate setting over night somewhat.

Re: Hydraulic Oil is milky amber in appearance

Reply #4 –
After setting a few days if you have the chance, crack open the drain plug on the tank and see if you can drain some of the water out.
I had a '71 Mack truck with a Cummins 335 engine with a pin hole in one of the liners. Every morning before starting I would open the drain plug and let it drain until the oil showed up then screwed it back in. It was still that way years later when broken engine mounts put the fan through the radiator while low bedding my 977 Cat enough damage terminated the truck.
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: Hydraulic Oil is milky amber in appearance

Reply #5 –
Is there a cooler for the hydraulic system? I need to go down and trace the hydraulic lines.
2003 U320 4010 - SOLD
2014 RAM 1500 Ecodiesel

Re: Hydraulic Oil is milky amber in appearance

Reply #6 –
On my 99 there is a oil cooler for the hydraulics and it is oil to air. Maybe yours is oil to water.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Hydraulic Oil is milky amber in appearance

Reply #7 –
Oil to air cooler between CAC and radiator. No possible leakage in to oil. Condensation? Drawing moisture in during cooling cycle after shutdown?

Re: Hydraulic Oil is milky amber in appearance

Reply #8 –
Quote from: dsd –
Condensation? Drawing moisture in during cooling cycle after shutdown?

Possible, but have never seen/observed/experienced it.
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: Hydraulic Oil is milky amber in appearance

Reply #9 –
If the seal on the cover of the hydraulic reservoir is bad then a hard wind driven rain could blow water into the reservoir. I worked on one several years ago that the oil was milky too. It had also had the steering box replaced previously. I thought that possibly a different type of oil was put in, still think water. I drained it, replaced the filters and filled it with new 15w-40 engine oil and removed the return line and ran until clear, then hooked up the return line and refilled. No further problems. I also replaced the rubber seal on the lid.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins
 

Re: Hydraulic Oil is milky amber in appearance

Reply #10 –
I just had the same thing on my coach. Took cover off and found there was no gasket on cover.
Gary and Darlene
2008 Nimbus SE 4030 Tahoe
Build #6463