Hydraulic fluid color

notop

Seaman Apprentice
Joined
Feb 24, 2011
Messages
37
I have a 1986 Force 125, runs like a charm, but I hit a log and burst the tilt lines when the leg kicked up. Replacement parts in hand, and I?m almost ready to put it back together.
Now, from what I know, the tilt system uses either traditional hydraulic fluid, which tends to be brownish, or it uses power steering fluid, which tends to be reddish. And never the twain should meet, or seals will rot, so I?m told. Fair enough, I can live with that.
But the fluid that came out of the system when the lines burst was GREEN. I?m talking bright green, almost fluorescent, just two shades from some engine coolants that I?ve seen. It was definitely oil though. Anybody know what kind this might have been, or what I can replace it with?
I?ve seen some bio-degradable hydraulic oils on the ?net listed as ?green?, but I think they?re referring to its environmental qualities, not its color. Any ideas?
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
flush whole sysstem, 30W NON detergent oil is what you need.

Power trim/tilt systems are about the simplest of hydraulic systems.

Back in Mercruiser #1 days they recommended using Mercury Power Trim oil or "MS" oil which was an engine oil (that doesn't exist today of course)

Nowadays, They still suggest their own power trim /power steering oil or as the Mercruiser Service manual says:
IMPORTANT: If quicksilver Power Trim and steering fluid is not available, SAE 10W-30
or 10W-40 engine oil can be used in the system.

They don't mention anything about non-detergent. It likely doesn't make any difference....... Just about ANY light oil can be used in the system. I probably wouldn't use Marvel Mystery oil though......(That stuff is probably only good for starting bon-fires!)

Regards,


Rick
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,075
30w oil is what you use.
Some put in power steering fluid.
It's supposed to eat the o-rings.
Some use tranny fluid.

Make sure you flush out the old oil.

MMO has saved an engine or two for me.
I've freed a few locked up motors with it.
But it does help getting fires going too. :)
 

notop

Seaman Apprentice
Joined
Feb 24, 2011
Messages
37
Okay then -- thanks guys. Will flush with mineral spirits and fill ?r up with 30W non-detergent.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,075
What do you use to flush out the mineral spirits? :)
Just open one line at a time and run the motor as you add oil.
It will eventually flush out the old oil.
 

fisheymikey

Chief Petty Officer
Joined
Jul 30, 2012
Messages
450
i bought it from walmart. i had the same situation like Notop, i forget not sure which one i think its the 3rd from the transom. you remove the line and the engine should drop almost instantly. and i pumped it by hand a few times then ran the pump a few minutes like suggested. then i filled the resevoir again ran the pump again.did that a few times until i saw the mineral spririt almost perfect. then when i felt it was as good as possible. i did the same steps with actual 30w 2 times.then after a season repreformed the same steps without the mineral spirits. maybe its overkill but heck it worked for me.

maybe JJ5 is going to rip me a new one... lol
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,075
You cant over flush.
Flush until you think it's all out then flush some more.
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Okay then -- thanks guys. Will flush with mineral spirits and fill ?r up with 30W non-detergent.

Guys, I really think you're way over-thinking this.

ANY type of motor oil is OK. ATF is also OK. ATF mixed half and half with oil is OK. ATF does not "eat" seals. (there'd be a LOT of screwed up power steering systems, Mercruiser trim systems, John Deere tractor hydraulic systems etc etc etc out there if it did...............)

Putting solvent in a hydraulic system and running the motor is NOT OK. You do not have to flush it out.....a little remnant of ATF, PS fluid or other light oil mixed in with motor oil will not make any difference at all.

Just put oil in it and run it up and down enough times to purge the air out of the pump and cyls. It will foam for a while as you do this. If you use anything heavier than 30w, it will take longer to purge the bubbles. That system is no different than Mercruisers trim system. (I used Dexron ATF in my Bravo trim pump because it's red and I wanted to easily identify it if there was a leak)

You can use just about any light oil, PS fluid, ATF , JohnDeere Hygard, or any other hydraulic oil, detergent or otherwise.......

If it's contaminated with water, you should blow the system out with air where possible. If it's contaminated with other particulates (sand/dirt etc) , you may have to remove the pump and disassemble to clean it out. You can actuate cyls manually to clear them but if they have particulates in them, you'd need to open them up and manually clean. if they only had a little water in them you could connect hoses and manually push-pull with supply hoses immersed in oil or hyd-fluid that was diluted with a little solvent.

Regards,


Rick
 
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