Water in gearbox oil - a cautionary tale

[FordnMassey]

Hi,

I just thought I'd share a story of the water in the gearbox oil of a Massey Ferguson 35. On purchasing the tractor, the gearbox oil was very milky, so the presence of water was obvious. A change of gear oil surprisingly only improved it. Despite not being left in the rain and parked under cover, it was slightly milky soon after the change. Recently the hydraulic pump failed, so I pulled the top cover and removed the pump. The pump failed as a circlip/spring clip on the top of the pump rusted until it failed. In doing this repair, I found the gearbox retains about 0.5L / 1 pint of oil. But here's the kicker, there was "free" water in the gearbox. Evidently the oil will only mix with a certain amount of water, and beyond that, the oil will float on the water. This means free water settles onto the bottom of the gearbox and any hollows like where the circlip was. When draining the gearbox, the portion that won't drain will potentially be water.

Moral of the story, if the gear oil is heavily water contaminated, remove the top cover to allow access for removal of all the oil or flush the box, (suggestions on how would be great).

Happy days.

 

[Halftrack]

I just drained and flushed a right angle gearbox. It has a top, side and bottom 3/4 inch drain plugs. Turned it vertical and drained from the side plug. What came out could best be described as brown gravy. Used a suction air wand to blow air and mineral spirits inside to flush box. Flushed till clear residue and filled with 80/90 gear oil. I have used cheap auto tranny fluid in the past to flush with but none on hand. Another option would be to use mineral spirits straight, 2/3 full, flush and drain. I plan to repeat next spring and see what it looks like then.

With your gearbox, and those cavities holding water, I can only suggest a suction or blow hose to remove the water, hopefully moving it to a drain hole. Another possibility is to use the high ethanol gasoline to flush with as the ethanol will absorb the water.

 

[FordnMassey]

I just drained and flushed a right angle gearbox. It has a top, side and bottom 3/4 inch drain plugs. Turned it vertical and drained from the side plug. What came out could best be described as brown gravy. Used a suction air wand to blow air and mineral spirits inside to flush box. Flushed till clear residue and filled with 80/90 gear oil. I have used cheap auto tranny fluid in the past to flush with but none on hand. Another option would be to use mineral spirits straight, 2/3 full, flush and drain. I plan to repeat next spring and see what it looks like then.

With your gearbox, and those cavities holding water, I can only suggest a suction or blow hose to remove the water, hopefully moving it to a drain hole. Another possibility is to use the high ethanol gasoline to flush with as the ethanol will absorb the water.

Hi,
Thanks for the input. I like the high ethanol fuel idea, as any ethanol/fuel that remains can evaporate away.
My gearbox is all cleaned up now, hopefully, but that's a tip I'll remember.