Problem with inboard Betamarine 10hp

Crannog Rhod

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Hi all, I have a Shrimper 19 which has a Betamarine 10hp inboard engine. It's been fine all season but yesterday when I decided it was time to haul out for the winter, when I let go the mooring, I had no forward propulsion. Put it in reverse - no problem, back into forward and the propshaft started to move a little, back into neutral and forward again and it turned fine thank goodness! Luckily it was only 5 minutes to where the trailer was backed down a slip. Approaching the trailer I put her in reverse - again no problem. Forward again and no propulsion! We had enough forward momentum to take us onto the trailer and so the boat is now out of the water. But does anyone have any idea what the problem is? Can I fix this myself or is it a job for a marine engineer? Many thanks.
 

doug748

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Hi all, I have a Shrimper 19 which has a Betamarine 10hp inboard engine. It's been fine all season but yesterday when I decided it was time to haul out for the winter, when I let go the mooring, I had no forward propulsion. Put it in reverse - no problem, back into forward and the propshaft started to move a little, back into neutral and forward again and it turned fine thank goodness! Luckily it was only 5 minutes to where the trailer was backed down a slip. Approaching the trailer I put her in reverse - again no problem. Forward again and no propulsion! We had enough forward momentum to take us onto the trailer and so the boat is now out of the water. But does anyone have any idea what the problem is? Can I fix this myself or is it a job for a marine engineer? Many thanks.

Is it a Technodrive gearbox? If so it is a documented issue, give it a Google.

If it were mine (and I was intending to keep the boat long term) I would consider a new gearbox and swap it. You would then have a old gearbox to re-furbish....... sell or keep. These gearboxes are not expensive in the bloated world of boating finance, prob under £1000 even now.

.
 

Crannog Rhod

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Thanks for your quick response Doug. Interestingly I have a receipt that came with the boat that a new gearbox was fitted about 4 years ago. I certainly plan to keep the boat long term so it sounds like a new gearbox is the answer. Is there an easy way to tell if it's a technodrive?
 

Tranona

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It will be a TMC40 - standard fitment. If you do go down the new box route then make sure you get the correct ratio - there are 2 options and you probably have the 2:1. It will be marked on the plate. However, before you go down that route check that the adjustment on the operating lever and cable is correct as it may not be engaging fully. The problem with this gearbox is a rather weak clutch mechanism, but it rarely shows on small engines. The same box is used on the larger engines up to 30hp and it is normally on the 20hp and above that the problems arise. You should not need a new box after only 4 years of light use.

You don't say where you are based, but first step might be a diagnosis from a good Beta dealer.
 

Crannog Rhod

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Great info - thanks! I am in the Outer Hebrides where Beta dealers are thin on the ground! Very light use - it spent 2 years out of the water. There is a good marine engineer who has done work for me in the past - I'll ask him to have a look at it, check the adjustment etc.
 

doug748

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Thanks for your quick response Doug. Interestingly I have a receipt that came with the boat that a new gearbox was fitted about 4 years ago. I certainly plan to keep the boat long term so it sounds like a new gearbox is the answer. Is there an easy way to tell if it's a technodrive?

Here is the handbook with drawings:

TMC40P Gearbox Operators Manual

Yours is probably sprayed red and has an identification plate. Was it brand new or refurbished? It is seems important to change the transmission fluid every year as these boxes do tend to lose drive.....but usually after plenty of neglect.

.
 

oldharry

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I dont know this gearbox so cant comment on the clutch problems, but the symptoms are exactly those of an incorrectly adjusted control cable, which is (should be!) dead easy to check: Simply disconnect the cable at the gearbox end and operate the gear change control by hand. If its the cable, the gearbox will operate normally.

I said simple, except sometimes these things can be a pig to get to.....!

Always check the simple things first.... with the wisdom of one who as a youngster stripped down an entire car engine because the T/stat had stuck. :mad:
 

Crannog Rhod

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Thanks everyone for your suggestions. I have booked the marine engineer to have a look at it next week. This being the Hebrides it'll probably be in about a month but that's fine! 😄
 

alahol2

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This has come up several times before. The only possible solution I've come across was posted by 'Amlov' on this forum. He wrote
On the Beta Engines Facebook page there was a potential solution for this problem.

Apparently there was a technical bulletin issued in 2014 that gave some advice on how to set up the clearance for the cone clutch. Basically with the gearbox in neutral you slacken off the nut on the selector shaft. You then screw the allen bolt in until you are unable to rotate the output shaft. Then back the bolt off 3/4 turn and lock the nut back up.
The person posting this found it was a bit of a trial and error to get the bolt setting correct, but apparently it fixed the problem and it has been good for 100h since.

Sorry this is all second hand but if you speak to Beta I am sure they will share what they know about this procedure with you.
Apparently there was a technical bulletin TMC Technical Bulletin 019/2014 but it doesn't seem to be available on the web.
I'd second his suggestion of speaking with Beta, they are usually very responsive and helpful.
Good luck, let us know the outcome.
 
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