Identify this engine-

NickRobinson

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Volvo? circa? output? Thanks.
 
Looks like my MD2B from 1973 except that on mine the belt goes to the flywheel. Power was supposed to be 25hp.

I forgot that mine also has a starting handle.
 
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Age is not significant; it is how it has been cared for that matters. Properly treated these engines can go on for ever
As I wrote earlier, mine dates from 1973 and is still going strong. The previous owner mainly used it for leaving and entering harbours; in my case it takes me around 20 minutes to go from the pontoon to open water. He also had a whole lot of spares that came with the boat. Spares can be a problem and, if you do find what you need, chances are that they will cost an arm and a leg. Some replacements can be made if you have the facilities. When the original exhaust elbow split, the genuine casting would have cost me a small fortune, IIRC around STG700. I fabricated a replacement out of stainless steel; less than €50 for the material. Some parts are simply unobtainable. When I had an old MD6a (or 7a?) on the Centaur that I had at the time and some valves were unobtainable I replaced it with a modern Lombardini with fresh water cooling.
Today I would go for an engine that is based on the Kubota, something like Nanni, Beta or one of the many others. The reason is that there are Kubotas all over the world being used for non-marine duty and spares are interchangeable, readily available and tend to not have the 'marine' price tag. Another factor to consider might be the weight of the replacement and its effect on the boat's trim; old Volvos tend to be heavy beasts!
Just my thoughts, of course. ;)
 
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Thanks all-
So pretty old- Anyone wish to compare with the BMC 1.5 diesel? Four cylinder opposed to two, c.35hp instead of 25hp
Spares/consumption/maintenance/noise.

No comparison as they are completely different kinds of engine and unlikely that there would be a choice between the two in the same boat.

fuel consumption is a function of power demanded and essentially is much the same irrespective of the make. So, my 30hp engine uses the same amount of fuel for a given speed as the standard 20hp but runs at lower rpm to deliver the same power.

The Volvo is a low speed large capacity engine that is saltwater cooled. The basic mechanical bits potential last indefinitely in terms of hours, but in yacht use the weakness is corrosion from being full of saltwater and failure of the ancilliaries, particularly electrics and fuel systems. Spares are becoming scarce and expensive.

BMC 1.5 is a high speed automotive diesel marinised with freshwater cooling through a heat exchanger. Many thousands still in use world wide and spares for the basic engine relatively easy and cheap. Standard UK made electrics and fuel system from the period. Know for poor starting from cold, a bit noisy and rough by today's standards.
 
No comparison as they are completely different kinds of engine and unlikely that there would be a choice between the two in the same boat.

Actually at the time they were both new it was a common choice between these engines!


fuel consumption is a function of power demanded and essentially is much the same irrespective of the make. So, my 30hp engine uses the same amount of fuel for a given speed as the standard 20hp but runs at lower rpm to deliver the same power.

The Volvo is a low speed large capacity engine that is saltwater cooled. The basic mechanical bits potential last indefinitely in terms of hours, but in yacht use the weakness is corrosion from being full of saltwater and failure of the ancilliaries, particularly electrics and fuel systems. Spares are becoming scarce and expensive.

BMC 1.5 is a high speed automotive diesel marinised with freshwater cooling through a heat exchanger. Many thousands still in use world wide and spares for the basic engine relatively easy and cheap. Standard UK made electrics and fuel system from the period. Know for poor starting from cold, a bit noisy and rough by today's standards.
 
""
Originally Posted by Tranona

No comparison as they are completely different kinds of engine and unlikely that there would be a choice between the two in the same boat.""

I've been toying with elderly IP and Colvic motorsailer projects and yes, both engines and others figure in these.
Good point about difficult starting on the BMCs- I'd not come across that.
 
You say you couldn't get valves for a MD6A?

What am I doing wrong?
https://www.volvopentashop.com/epc/...42080_21/7742080_001B/7742080_000/7742080_001

Not sure if it was the 6a or the 7a (this was twenty years ago).
What I remember is that one of the valves (inlet? outlet?) was not available while the other one was priced at £47! The total quotation for what I needed from Valspec was around £850. Adding the shipping costs to that (Malta), I was fast approaching half of what a new engine would cost me. I opted for changing for a new Lombardini, fresh-water cooled, FOCS system, extras, etc., not to forget the three-year warranty.
That was twenty years ago and that engine is still running smoothly. I sold that boat around six years ago and she is in the same marina as my present one. She had been brought over from some place near Aberdeen and came via the French canals.
 
""
Originally Posted by Tranona

No comparison as they are completely different kinds of engine and unlikely that there would be a choice between the two in the same boat.""

I've been toying with elderly IP and Colvic motorsailer projects and yes, both engines and others figure in these.
Good point about difficult starting on the BMCs- I'd not come across that.

OK, with DIY type installations you might get more diversity. expect, though that the Volvo would be a bit short on power for anything bigger and heavier than the 20' versions. The BMC was a popular choice as there were very few 35hp engines on the market other than BMC or Perkins 4/107 or8 at the time, and you could do your own marinisation. so look carefully at who did the marinisation.
 
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