Re: SM leaking ATF fluid #solution

Mike Longcor (SV Trilogy)


I'm having the same issue with my HBW250. I'm guessing the repair will be similar. Just wondering if anyone has changed this seal before and has any tips/suggestions? Also, can anyone confirm the seal dimensions? I found online it might be SD 20x26x4 radial. Would be nice to have the correct replacement on hand and do the job in one go.


On Wed, Jan 15, 2020, 5:13 AM Rob Smith <robfromcornwall.1966@...> wrote:
Many thanks for your speedy reply. I believe it's the seal that has gone as that is where it is leaking from. I will have a go at changing it. 

Many thanks for your help. 



On Tue, 14 Jan 2020, 16:25 CW Bill Rouse, <brouse@...> wrote:

I have not personally experienced this issue. Your ZF 25 holds 0.75 liters of fluid. Is it possibly overfilled? You do not screw in the dipstick to check the level.

If not, it probably is a worn sealing ring. If so, maybe this will help you:

5.2 Removing and disassembling the
actuating lever cover plate

5.2.1 Always set actuating lever to neutral
5.2.2 Remove hex nuts (22) from cover
plate (9), using 13 mm spanner (wrench),
and take off spring washers (4).
5.2.3 Remove cover plate assembly (12),
lever (6) and actuating cam (11).
5.2.4 Remove screw (7) from lever (6).
Pull off lever (6). Remove actuating cam
(11) and needle bearing (70) only in
models ZF 12 M - 15 M - 25 M - 30 M.
Remove actuating cam sealing ring (8).


6.3 Assembling the shifting fork in
gearbox section side shifting cover

6.3.1 Insert shifting fork (15) into gearbox
section (1) side the actuating lever
in such a way that the long arm of the
fork points downwards.
6.3.2 Insert shifting rod (16) through
bores in gearbox and shifting fork.
6.3.3 Fit screw plug (17) to gearbox,
making certain that the clearance between
shifting rod (16) and screw plug
(17) is min. 0.5 mm (0.02 in).
Seal screw plug with Loctite 242 (ZF 3
M - 5 M only O-Ring).
6.3.4 Check shifting fork for easy
6.4 Pre-assembling the actuating
lever cover plate

Use punch tool to press sealing ring (8)
into cover plate (9). Spread antifriction
bearing grease between sealing lips.

6.4.1 Insert actuating cam assembly (11)
into cover plate (9).
6.4.2 Fit actuating lever (6).
Clearance between actuating lever and
cover plate 0.5 mm (0.02 in).
6.4.3 Clamp actuating lever by means
of retaining screw (7), using a 13 mm
spanner (wrench). Screw in with torque
of 20 Nm.

CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
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On Tue, Jan 14, 2020 at 8:28 AM Rob Smith <robfromcornwall.1966@...> wrote:
Hello I have ATF fluid leaking from the gear lever on my gearbox.
Any suggestions?

Rob smith

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