Yanmar 1GM10 to Beta 10hp replacement

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engineer54

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I've got salt water ingress problems with my Yanmar 1GM10 diesel inboard and due to the extremely high price of spare parts for a rebuild I am (reluctantly) thinking about replacing it with a new Beta 10hp. I'm not keen on getting involved in major modifications to make it fit and I wondered if anyone has experience of doing this swap? My boat is a Sadler 25.
All advice will be very welcome.
Thanks,
Ronnie
 
If you are going for it, buy the new engine during the forthcoming LIBS. Discount is much easier to negotiate, even if you order by 'phone.
Beta fit 50mm exhaust as standard, ask if they have same size as Yanmar, ( 45mm? ) they supplied mine with a non-standard size to suit my existing system.
Check that the cooling water inlet is OK, Yanmar might be 12mm, Beta standard is larger.
 
Beta are excellent - they will also make the engine bearers to the same width as your bearers. Also I strongly suggest you go for the 14HP - it's the same capacity as the 10HP and I got an upgrade to the larger engine from the one I'd originbally asked for. Definitely go to LBS and you should get a good sicount. Also check prop rotation, you may need a new prop, also consider non-drip stern gland, new/extra sound insulation, check exhaust size, you may need new water trap and gooseneck.
 
Changed my 1GM10 for a Beta BZ482 13.5hp, and would recommend it. The 10 and the 13 are the same physical size. If you have a 12 x 9 prop you will be able to use it with the 13.5 as the gearbox reduction is less.

Exhaust is on the opposite side of the engine, so you will need to plan how to manage this during the installation. Beta do a swap over exhaust if you want to keep it the same side.
 
Yes, I'm thinking of going to the LBS next month. I like what I hear about the Beta engine but the fitting is made more complicated and expensive by the amount of other changes which need to be made, as you have mentioned above. It would be much simpler to buy a new Yanmar 1GM10 but I have been put off by the eye-watering price of their spares and the fact that it is now an old design. Ideally I would rebuild my old engine but the spares I need could easily come to £1000 just to get it running again.
 
Thanks Pye-End. I was wondering about the prop situation. I've been looking at the overall size of the Beta unit. It's slightly higher and wider than my Yanmar, which is already a tight fit in the Sadler 25.
 
engineer54 said:
Thanks Pye-End. I was wondering about the prop situation. I've been looking at the overall size of the Beta unit. It's slightly higher and wider than my Yanmar, which is already a tight fit in the Sadler 25.
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Have just done it - but with a Nanni 14 essentially the same engine. Would recommend you get a 14 (either Beta or Nanni). Dimensions are virtually the same. 10mm longer, bit bulkier at the top aft for the extra cylinder and the engine mounts slightly further apart fore and aft but virtually the same distance apart across. Bit higher. I put a 15mm packing piece on my bearers to avoid having the mounts at the top of the adjustment. As already said the exhaust is on the other side and it is 50mm diameter on the Beta or 40mm on the Nanni whereas the Yanmar is 45mm. I used an adaptor on the inlet to the water trap and used the original exhaust. The control cables come in at different angles and on the opposite side. You will need a 3/4" water inlet rather than the 1/2" you have now and worth fitting a water strainer if you do not have one.

You have to be careful with props as it depends on what gearbox ratio you have. The Yanmar has a choice of 3, whereas the TMC box has only 2, with the 2:1 and a 12*9 prop being the most common. There is a 2.6:1 if you have a larger prop, but not an equivalent to the Yanmar 3.1:1. However, it is unlikely that you have that as it is usually used to swing a 14", or even 15" fine pitch prop.

If you are going to buy new definitely worth going for the 2 cylinder as it is much more refined. However you are looking at around £4k minimum which buys a lot of spares, even at Yanmar prices - and you won't find Beta/Nanni spares much cheaper, although hopefully you won't need them.
 
engineer54 said:
I've got salt water ingress problems with my Yanmar 1GM10 diesel inboard and due to the extremely high price of spare parts for a rebuild I am (reluctantly) thinking about replacing it with a new Beta 10hp. I'm not keen on getting involved in major modifications to make it fit and I wondered if anyone has experience of doing this swap? My boat is a Sadler 25.
All advice will be very welcome.
Thanks,
Ronnie
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We replaced the 1GM in La Roca (SM Sailer 23) with a Beta 16 a year ago and are delighted.
 
No. An old Eventide, but similar space constraints, particularly length. Maximum height comes out a few mm higher at the front. Overall it is the easiest swap as the engine was configured to be a replacement for the Yanmar.

I changed to the 14 for the extra power. The Yanmar is still going strong in another boat.
 
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selling the yanmar

Tranona said:
You should be able to sell the Yanmar quite easily even if not perfect.
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I actually replaced a 2GM20 with a Beta 20. just so much better and smoother. the head on the yanmar was corroded, the injector pump needed overhaul and the cost would have been 50% of a new beta.
Beta were brilliant, and I sold my old engine to a man who never paid for it or collected it. Three months later I stripped down the engine and made almost 1500€ on bits and pieces.
Yanmar's are old technology, very expensive for bits and noisy compared with a new beta
 
Thanks. You are right, I could get back some of my costs by selling Yanmar as spares. I think my best course of action would be to go for a Beta 14hp. It would give my boat a new lease of life.
 
engineer54 said:
Thanks 25931, that's encouraging. Was the Yanmar giving problems or were you just wanting a newer, more powerful engine?
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The Yanmar had been giving problems which appeared to have no probable end it sight. Whilst my pal and I both enjoy the occasional challenge the novelty had worn off. Fitting the new engine was fiddly rather than difficult because the dimensions were remarkably similar. We have only needed full power once (but it was good to have it) when crossing the Faro/Olhão bar against the main ebb on springs which can reach six knots.
 
Yes you are right about the additional power. When it is working correctly the little 1GM10 Yanmar drives my boat along quite nicely under normal conditions. However I always feel that it's working at the top end of its power range and there's not much in reserve for punching against a tide or strong head-wind. Last season I didn't go anywhere with it because the compression was so low it wouldn't even start!
 
One day I expect my 1GM10 will have to go. When it does, I may give Beta a miss. It seems to me that there is general doubt about them on these forums ... a suggestion that they may be a bit cheap and cheerful. Perhaps I'm wrong, but on the whole it seems that I see good reviews from people who have just fitted Betas and worries about, for example, heat exchanger longevity, from those who have had them longer.
 
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