Changing transmission oil

[WindLove]

I'm sure everybody has different thoughts on this. I regularly change engine oil, but never transmission fluid. Is there a "rule of thumb" for how often I should change it? My engine is a Volvo, but I don't even know who made the transmission....

[Jim Cate]

Don't know about your specific installation, but
Hurth or ZF trannies, which have a reputation for fragility, recommend changing the ATF in them each time you change the engine oil. Folk wisdom agrees with this, as evidenced by many posts here and on mechanical subject fora. We've been doing this ever since we bought this boat (11 years now) and so far, so good!

Cheers,

Jim

[WindLove]

Originally Posted by Jim Cate

Don't know about your specific installation, but Hurth or ZF trannies, which have a reputation for fragility, recommend changing the ATF in them each time you change the engine oil. Folk wisdom agrees with this, as evide

WOW.. I had no idea it would be that often. I thought it was maybe every 500 hours or even more. After all, it's not a car where you are changing gears all the time. You go from neutral into gear and stay that for hours or until the wind picks up.

[Jim Cate]

In an automotive transmission you don't have the clutch mechanism included as is the case with marine "reversing gears". It is the clutch bits that usually fail, at least in the aforementioned Hurth/ZF units. And, in the case of our ZF10 box, there is only 375 mL of fluid, and it runs pretty hot. This likely speeds up the decay of the oil.

Other marques are likely less picky... once you discover who made your trannie you can do some rersearch via Google and get the lowdown.

Cheers,

Jim

[ranger58sb]

Our ZFs specify once/year at least, and I think there's also a "more, depending on how many hours run" option. Your manual will say (and there's likely a maker's tag on it somewhere).

Not all gears use ATFs; ours require straight 30W.

-Chris

[Maine Sail]

Originally Posted by Jim Cate

Don't know about your specific installation, but
Hurth or ZF trannies, which have a reputation for fragility, recommend changing the ATF in them each time you change the engine oil. Folk wisdom agrees with this, as evidenced by many posts here and on mechanical subject fora. We've been doing this ever since we bought this boat (11 years now) and so far, so good!

Cheers,

Jim

Bingo!! And changing the gear box fluid is less costly & even easier than an oil change.

Our ZF takes exactly 1 quart of ATF. It is changed at every oil change and takes all of three minutes.. First I suck the ATF out the dipstick hole, with a Moeller Fluid Extractor pump, then unscrew the drain plug and it empties the rest onto a oil pad (very little comes out).. I then re-install the drain plug and pour in a quart.... Three minutes max....

Different gears take different fluids and differing capacities but all are pretty easy to change, if you have good access.......

[Pete7]

Volvo manuals are on line including the older models:

inboard - Inboard : Volvo Penta

Our 2003 is every 200 hours or annually. We actually do it every two years.

Pete

[nigel1]

You'll need to find out the type of transmission. I have a VP engine(re-badged Perkins). Gear box uses 700ml ATF, I change it yearly.
There should be a makers plate on the gear box which will identify it for certain.

[Dsanduril]

And our Volvo 2003 manual says every 400 hours or annually. Note that the MS2 gear on ours calls for the same oil as the engine oil, not ATF. So, you'll really need the engine/transmission manual to determine the correct materials and timing.

[gjordan]

This depends on what model Volvo you have ? Early MD series Volvos dont have a separate oil sump. The engine oil circulates through the transmission, and gets changed every time you change your engine oil. Later models went to a more modern transmission with its own oil supply. Your manual should make it clear which you have. _____Grant.

[wingless]

The oil and filter in mine is changed per the manufacturer's schedule. I have both transmissions plumbed into my five-zone oil change system. Here is my oil change system.

[WindLove]

Originally Posted by wingless

The oil and filter in mine is changed per the manufacturer's schedule. I have both transmissions plumbed into my five-zone oil change system. Here is my oil change system.

Whoa.... I sure don't need my sailing life to get that complicated. Looks like fun though.

[Tynesider]

Hello Windlove

Like many others I have also had to change my Hurth gearbox to a now ZF 10 box and I had a few good conversations with them at the time.

ZF recommended some good point to watch to prolong the life of the gearbox, A) Always use ATF oil, B) change the oil every 100 hrs or 12 months whichever is the sooner, C) do NOT overfill the gearbox

[ranger58sb]

Originally Posted by Tynesider

Hello Windlove

Like many others I have also had to change my Hurth gearbox to a now ZF 10 box and I had a few good conversations with them at the time.

ZF recommended some good point to watch to prolong the life of the gearbox, A) Always use ATF oil, B) change the oil every 100 hrs or 12 months whichever is the sooner, C) do NOT overfill the gearbox

In the ZF 10. Other ZF gears use different lube...

-Chris

[ericlo]

Hi Jim, you seem to be the person who can help me out with the problem I have on hand. My boat has a Yanmar 3JH2E engine fitted with a Kanzaki KBW10 gear box. Two months ago, I had a mechanic changed my oil when I was going away from my boat. Just found out that the mechanic had put in regular engine oil into the gear box instead of the ATF oil specified. How can I correct the mistake? Can I just pump out the engine oil and put back the red ATF? What about the clutch which has been soaked in engine oil for months. Any problems there? Eric