Hurth ZF45 IV (SeaVee) gear box

[.NOBODY]

So............600 hours and 9 years of use, the gear box had milky oil caused by a leaking raw water cooler (integrated), but also caused s really loud screech after about 3 minutes of running (No load, on trailer, 2000 rpms).

It seems everything that doesn't normally fail, is failing this year, like my Teleflex clamp.

Since Dom @ Forte's hasn't seen any failures on the SeaVee gearbox, has anybody else seen bearing failures.

SeaVee gear box.JPG

[KoolAid]

I am surprised Dom hasn't seen one. That man has seen everything lol! I don't recall ever seeing one fail either. I'm sure the bearings went out because of the lack of lubrication (the water in the oil) and it was too late when you noticed it was milky. Did it make this noise after you drained and refilled the unit?

[.NOBODY]

ZF Hurth ZF-45-1 IV Transmission 20°

I am surprised Dom hasn't seen one. That man has seen everything lol! I don't recall ever seeing one fail either. I'm sure the bearings went out because of the lack of lubrication (the water in the oil) and it was too late when you noticed it was milky. Did it make this noise after you drained and refilled the unit?

Totally agree. Dom knows everything. He's the master.
So I just decided to pull it out and open it up. Your assumption is correct. The raw water got into the oil (SAE30 / 1 litre) through the water pipe and made it milky.

One of the bearings was indeed starting to go bad.

It took a good deal of searching but I found the repair manual.

http://www.bukh-bremen.de/files/346/...%2045%20IV.pdf


http://jerrysmarinecatalog.com/files...s/page0169.pdf

[KoolAid]

If you cannot find a supplier of the replacement bearings you should be able to take it to a local bearing supply place. They should be able to read the numbers and order you a replacement. I'm sure they were pressed on .002" tight so you may need to take both shafts to a machine shop to have them pulled. Or use dry ice on the shaft only and use a stout bearing puller. If you don't know how to pull them, leave it to the people who know best. On the seals if you can't find a source for them, your local hydraulic supply/repair facility should carry them and if not they can order them. Both the seals and bearings i'm sure ZF didn't design considering parts like that are readily available for manufacturers. Worked at a machine shop that repaired industrial gear boxes and hydraulics. I learned a thing or two ;-)

[.NOBODY]

If you cannot find a supplier of the replacement bearings you should be able to take it to a local bearing supply place. They should be able to read the numbers and order you a replacement. I'm sure they were pressed on .002" tight so you may need to take both shafts to a machine shop to have them pulled. Or use dry ice on the shaft only and use a stout bearing puller. If you don't know how to pull them, leave it to the people who know best. On the seals if you can't find a source for them, your local hydraulic supply/repair facility should carry them and if not they can order them. Both the seals and bearings i'm sure ZF didn't design considering parts like that are readily available for manufacturers. Worked at a machine shop that repaired industrial gear boxes and hydraulics. I learned a thing or two ;-)

Thanks for your help KoolAid. We took it apart and found a burn mark on one race and over heating on roller surfaces. I'll take photo's and give more details in hopes it helps someone else down the road.

[Jetdriver]

Nobody, I'm going to be taking my drive and tranny out in the next couple days and was wondering how you went about removing yours? Did you seperate each component or pull both the trans and drive out together? Any tips are appreciated. Thanks!