TMC 40 gearbox problem

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andrescel

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I have a TMC 40 gearbox in a BetaMarine 30 Hp engine mounted in a Dufour 31.
I just bought the boat a month ago and sailed some 1000 NM many of them motorsailing (like 400).
The last days I found difficult to engage the forward gear. Once it goes in it works perfectly the whole day. Reverse works great.
The engine is ten years old and ok maintained. When I bought it I changed the oil, ATF, filters, hoses...
The weird thing comes today when I start to look for the problem. Before checking the morse cable or anything y decided to check and change the ATF. Check: The dipstick comes with clean (really clean) fluid and between the max and min marks. Then I open the drain screw and, surprise! The fluid that comes out, is very dark, almost black and dirty.
I haven´t had more time today to do anymore checks, I just refilled the gearbox with 200 Ml new ATF. But I guess I should open the gearbox to see what´s going on inside¿?
A month ago when I first changed the transmission fluid I didn´t find the drain plug, so I just succtioned it from the "filling hole".

The engine works great and even the gearbox when it´s hot it works flawless.

Any toughts?

Is the first time I post in this forum. I´ve read a lot, but never written... I hope I didn´t forget to introduce myself or something like that...

Thanks!
 
I suspect the morse control isn't set up correctly and the revs are starting to rise before it is properly in gear. That will burn out the cone clutch and produce the black fluid you're referring to. Definitely worth checking and very easy to remedy. The trouble is you may have already worn out the clutch if it won't now go into gear, although the reduction in revs might help

Worth checking before going further. You just need an assistant or two to watch the gear level and throttle (at the engine end) when engaging forward and reverse gear. It should be fully in either forward or reverse before the throttle starts to move. Stick the details of your morse in Google and you should find details of how to adjust it - it's not difficult and you should be able to figure it out even without the manual

I'm guessing you have something like this?

http://marineparts.ie/images/detailed/17/TX172103.jpg?t=1425054564

You can also adjust the travel at the gearbox end and a combination of the two should sort it out
 
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andrescel said:
I have a TMC 40 gearbox in a BetaMarine 30 Hp engine mounted in a Dufour 31.
I just bought the boat a month ago and sailed some 1000 NM many of them motorsailing (like 400).
The last days I found difficult to engage the forward gear. Once it goes in it works perfectly the whole day. Reverse works great.
The engine is ten years old and ok maintained. When I bought it I changed the oil, ATF, filters, hoses...
The weird thing comes today when I start to look for the problem. Before checking the morse cable or anything y decided to check and change the ATF. Check: The dipstick comes with clean (really clean) fluid and between the max and min marks. Then I open the drain screw and, surprise! The fluid that comes out, is very dark, almost black and dirty.
I haven´t had more time today to do anymore checks, I just refilled the gearbox with 200 Ml new ATF. But I guess I should open the gearbox to see what´s going on inside¿?
A month ago when I first changed the transmission fluid I didn´t find the drain plug, so I just succtioned it from the "filling hole".

The engine works great and even the gearbox when it´s hot it works flawless.

Any toughts?

Is the first time I post in this forum. I´ve read a lot, but never written... I hope I didn´t forget to introduce myself or something like that...

Thanks!
Click to expand...

I believe this is a known problem with this gearbox but there seems to be little written on the causes, cure or prevention. Just that it slowly gets worse until it does not engage forward gear at all. I suspect a slight mall adjustment causes wear on the internal selector dog.
 
Any particles generated in a wearing clutch would soon settle out, explain the dark dirty oil at the bottom, yet a clean dipstick.

If you can get the parts and ideally a manual replacing a clutch isn't that tough an ask, but will require an experienced mechanic, and possibly some special workshop tools like a press.
 
I had similar trouble with a TMC30 on my son's little open boat. Problem was that there was no replacement available for the double cone; they are not made anymore. In the end he decided to replace the box with a PRM.
 
Thank you all for the answers.
I hope is not that bad. It happened just twice or three times... Today I´ll check the morse controls and hopefully sort it out!
Thanks!
Cheers,
Andres
 
I'd still put money on the morse adjustment causing the problem. Whether or not this recoverable will depend on how far out of adjustment it's been and for how long. Here's another thread you may want to take a look at:-

http://www.canalworld.net/forums/index.php?showtopic=16929

Try disconnecting the cable from the gearbox and operating the lever by hand. Hopefully it will go into forward but if it doesn't it still could be the morse setup up that was at fault as the damage may already have been done. Or it could be something else completely :-) But rule this out first

I get the feeling that people slap the morse or new cables in and leave well alone if it works, which causes problems down the line, rather than setting it up correctly
 
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Your Morse may have been a bit slack, and adjusting may get you going well enough. But ...

We had a TMC40M gearbox installed in April 2005 with a Beta 28HP. After 30 hours I changed the fluid, using Comma ATF fluid. The fluid was rather black.

The gearbox worked well for the first 3 years - ie past the warranty. In the 4th year the gearbox became a problem. After not using the engine for many hours, for example after resting at night, it wouldn't turn the propeller shaft for forward motion. Selecting reverse was good, but forward was bad. By selecting reverse, then forward and reverse again etc, it was sometimes possible to move into forward gear. At other times the engine was run fast, and the gear would suddenly enter.

Next winter I asked an engineer to inspect the control levers, and adjust the clutch if necessary. He adjusted the clutch by 0.75 of a turn. But the problem was there again when the boat was put into the sea, and the old fluid was black. I changed the fluid again. It didn't remove the problem.

Eventually we had the gearbox out for inspection. The item that failed was part ref 27, Clutch, code 2056129. I call it a pair of bronze friction cones. They are coated with a black high friction surface. The cone for forward had worn down, but the reverse cone was OK. The worn off black material had been mixing with the fluid.

I got a replacement from Italy through JBJ Techniques Limited, 28 Trowers Way, Holmethorpe Industrial Estate, Redhill, Surrey RH1 2LW.

It's been fine since. Hardly anyone reports problems with these gearboxes. I guess that I was unlucky with a badly adjusted or poorly coated cone in the factory, and it may have been slipping and wearing since installation without us realising.
 
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andrescel said:
I have a TMC 40 gearbox in a BetaMarine 30 Hp engine mounted in a Dufour 31.
I just bought the boat a month ago and sailed some 1000 NM many of them motorsailing (like 400).
The last days I found difficult to engage the forward gear. Once it goes in it works perfectly the whole day. Reverse works great.
The engine is ten years old and ok maintained. When I bought it I changed the oil, ATF, filters, hoses...
The weird thing comes today when I start to look for the problem. Before checking the morse cable or anything y decided to check and change the ATF. Check: The dipstick comes with clean (really clean) fluid and between the max and min marks. Then I open the drain screw and, surprise! The fluid that comes out, is very dark, almost black and dirty.
I haven´t had more time today to do anymore checks, I just refilled the gearbox with 200 Ml new ATF. But I guess I should open the gearbox to see what´s going on inside¿?
A month ago when I first changed the transmission fluid I didn´t find the drain plug, so I just succtioned it from the "filling hole".

The engine works great and even the gearbox when it´s hot it works flawless.

Any toughts?

Is the first time I post in this forum. I´ve read a lot, but never written... I hope I didn´t forget to introduce myself or something like that...

Thanks!
Click to expand...

Hello my friend,

I have the exact same problem on my Beta 30 with TMC40 transmission. My problem came alive after only 500 hours and while I was sailing around Sicily from Malta. I can assure you it's not the cables but it is a defective gearbox. This problem seems common on TMC40

While I was sailing around Sicily during the last weeks, I noticed that the engine is slightly revving up (100rpm or so) without me touching the throttle, and I could see the rev counter playing and also hearing the engine revving up. The gearbox engages and disengages or slips, so it revs up when disengaged and then back to preset revs when engaged. And I confirmed this problem because when I entered Palermo marina with reverse to park, then the forward didn't engage in order to stop the boat from bumping into the dock. The problem only occurs when the gearbox oil is hot and on forward only. Once in Palermo, I checked that the throttle cables and linkages are still in place. I also checked the gearbox oil and it was on max and reddish on the dipstick, however when I changed it, it was pitch black. Please note that I change the gearbox oil every year according to the manual, and I use Automatic Transmission Fluid (ATF) 0.2 litres precisely. The problem was that I was in Palermo and needed to return to Malta. What I did was changing the gearbox oil in every marina I stopped, and each time I changed it, it was always pitch black, even after 4 hours of working.

The gearbox failed me completely and I felt so frustrated that all went well but I had to return to Malta due to the transmission. One time the gearbox stopped completely in the middle of the sea and didn't want to engage at all. Thank God the sea was calm so I had the chance of changing the oil again. Then it works fine until the oil loses its properties and becomes like water without any viscosity.

And now that I know that the gearbox is slipping, I think it was defective from day one cos I always heared a little whistle noise between 1300-1800rpm and I always thought it was coming from the shaft bellow or vibrations cos it always moved forward without problems and never slipped or revved up until lately. Never occured to me that I might have problems with the gearbox, never!
 
Best solution is a replacement PRM, should be an easy swap but never done one.
Ask PRM, they are very helpful
Calcutt Boats in Napton were the best priced agent for PRM last time I needed one.
 
This is the oil after few hours of working ... pitch black
 

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