Linkage adjustment on ZF 25ma

[TrailerCruiser]

I'm having a transmission engagement issue related to installing new ZF 25ma. The problem is periodically when shifting into forward the transmission doesn't go into gear. It seems to stay in neutral. I have no problems going in reverse.

I am wondering if my issue is related to my shifter cable travels further when going into forward more than it does when going into reverse.

Any thoughts on cable distant travel and transmission shifting much appreciated.

[skipperpete]

Originally Posted by TrailerCruiser

I'm having a transmission engagement issue related to installing new ZF 25ma. The problem is periodically when shifting into forward the transmission doesn't go into gear. It seems to stay in neutral. I have no problems going in reverse.



I am wondering if my issue is related to my shifter cable travels further when going into forward more than it does when going into reverse.



Any thoughts on cable distant travel and transmission shifting much appreciated.

ZF take this issue very seriously and there’s 3 pages of adjustment instructions in the ZF 25MA workshop manual. Here’s a screenshot of the basic angles, (these are important if you wish to avoid clutch slippage and selector wear

[FPNC]

Disconnect the cable. Shift the lever by hand. If the transmission slips, you are in for a rebuild. Your only chance would be to adjust the side plate bolt up position of the shift lever assembly. But it's not a good chance. You can try running Type-F ATF fluid which is a bit less 'slippery' than Dex III. Good luck.

[BjarneK]

Originally Posted by TrailerCruiser

I'm having a transmission engagement issue related to installing new ZF 25ma. The problem is periodically when shifting into forward the transmission doesn't go into gear. It seems to stay in neutral. I have no problems going in reverse.

I am wondering if my issue is related to my shifter cable travels further when going into forward more than it does when going into reverse.

Any thoughts on cable distant travel and transmission shifting much appreciated.

We had the same issue with the same transmission. It started after about a year from new.

I was never able to solve the issue and ended up replacing the transmission.

It would shift fine when the transmission was warm (after motoring for a while), but not when cold.

[TrailerCruiser]

The transmission is brand new. It was working just fine the first couple of times I used the boat. I hope it doesn't already need to be rebuilt.

I've removed the cable and run the motor. When I shift it into gear the shaft starts spinning but slowly. Some times it never goes clunck and engages fully, some times it takes a while and then goes clunch and starts spinning faster.

Hope it doesn't already need a rebuild.

[TrailerCruiser]

Skipper Pete,
do you have a link to a PDF where you got the diagram?

[skipperpete]

What engine is this gearbox attached to ? If the idle is too slow you might have problems because of that. The oil needs to be an ATF as posted by FPNC and the level is checked with the dipstick NOT screwed all the way in, just sitting loose in the hole.
I’m wondering what the alignment between the propshaft and gearbox is like? but try bumping up the idle speed and do the test with the lever again.
If all else fails, you have reasonable grounds to make a warranty claim.

[skipperpete]

Here are the relevant pages for the ZF25.

[Lightspeed85]

So I'm having this exact same issue on a new to me Bavaria 47 with VP TMD22P-C engine. Gearbox is certainly not new and probably has some wear and tear, but I'd like to attempt this before considering rebuild or likely replacement.



The ZF workshop manual references a special bracket used for the alignment. I can't find this part number anywhere on the web. Is it necessary for the adjustment procedure? Thanks!

[FPNC]

p/n 20.4039.02 I use to work for ZF and I have never actually seen this part /tool. Mechanics that use it just make one. It is just a flat plate that allows you to mark the swing of the lever. It can be cut from sheet metal. I may have the dimensions if you PM me I will send it.