It has been some time since I was active on the forum as my sailing has been very very limited for some time now. I still have the boat however and am holding out for the time my circumstances change enough for me to get out regularly once again.
I thought I would pose this question to the forum as an interesting discussion point. I have reached my decision so I'm not seeking suggestions but rather the general thoughts of those on the forum. I suspect the following is a place many of us come to as some point with our boats.
I have an ageing (30+ years) old yacht that still has the original engine in her. The engine has been quite reliable but is requiring more and more TLC to keep it chugging along (its a Volvo penta engine but I'm not even sure of the model because I can't read the plate with the model number written on it any more). Most recently it started leaking fuel from the fuel pump which will cost $1000 minimum to have repaired. It is also pumping less and less water through the cooling system as time passes. Some time back I did have my mechanic remove the raw water pump and associated bits to give them a good service and clean out which did make a difference bit we are back there again.
Given the age and value of the yacht it would probably cost me as much (if not more) than the boat is worth to repower with a new engine so I have decided to just keep the old one going for as long as possible. Hopefully by the time it completely dies I will have won lotto or something.
So what are peoples thoughts? Would you bite the bullet and repower and have the piece of mind knowing you had a new reliable engine or would you keep the old one on life support knowing it was going to cost you a fair amount of $ in much smaller chunks to keep it going? Are there other options you would consider such as a reconditioned/rebuilt engine?
Depends on model and use
If a 2003 or similar for instance, the water problem is not the pump but the mixer where there are two small galleries which clog and need to be cleaned every few years,
If it is a 7MB then I have mate that has 12000hrs on one without a rebuild.
A few years ago I brought a boat for restoration with the expectation I would need to repower straight away.
With minimum work on the cooling system a few weeks later the engine was started and ran from Brisbane to Hobart with one stop and was completely trouble free.
The latest renovation was brought with the expectation that the existing engine could be made good quickly but the new 27hp got ordered earlier this week.
So depends on the facts.
I had the same issue last year,I do all my own work and have no problems tearing an engine down and rebuilding.when I went north I wanted a reliable engine and the old Volvo although still running ,was not in a trustworthy condition. I repowered with a beta 25 only because the critical parts for my Volvo are no longer made and if one of those parts failed I would be stuck . If all parts were available it would have been a rebuild.
Agree parts become a problem, in an old boat I had a Perkins V8510.
Great condition and ran beautifully, but the prospects of not been able to get parts or having them made was the problem.
Ive been asking the same question. My old Volvo 2003 goes well but its been doing that 25 years and I dont know whats happening inside it. It sounds good, produces its 28hp no problem, but something inside may be 1 hour away from breaking. Dont know.
I think the answer depends on how long you want to keep the boat. I want to keep mine so I will re-power it before long. If I sail it around for the next 15 years and it costs $15K to re-power it thats $20 per week and I think its worth that to know the motor wont die suddenly or refuse to start when I need it.
But if keeping the boat for only 1 year - probably not worth it. Thats $300 per week. Unless you're planning a trip where motor is critical.
Depends on the Volvo. If it's a real marine engine, large flywheel on the front like the Md7b for example then keep it. If it's one of the converted cement mixer type or automotive type of motor then it's a different story. I presume when you mean the fuel pump is leaking you are referring to the injector pump leaking! A $20 electric fuel pump off eBay will be a cheap alternative if the lift pump is faulty. I would also get your "mechanic" to check the thermostat is not stuck.
Post a photo here or check out a few YouTube videos till you find the same engine.
Yep 2003s defy all logic, most should have been landfill years ago but keep going on.
Light, raw water cooled and the only real defect is the gearbox spline which would let go at almost exactly 1000 hours but the replacement was heavier and was never a problem.
and you need to remove and clean the mixer galleries regularly
Longer you kept them running the better.
My boat is the same age as yours with it's original engine ( Bukh DV10 ). I had cooling problems and found
it was due to salt build up in the engine block. I took out the thermostat, isolated the water pump, drained the
block and filled it with a mixture of brick clean and fresh water 50/50. It bubbled and frothed for at least a couple
of hours and I left the mixture in there for 24 hours and then drained it. The water was bright green with disolved
salt and I've never had a problem since. If these old engines are in anything like reasonable nick...you can't kill 'em.
I have heard that the Nanni diesels are quite competitive now. I suspect if you were paying someone to refurbish an old motor, it would be cheaper to replace it with a brand new blue Nanni.
Which makes me then think there is nothing to loose if you attempt a DYI refurb !
A
It is a valid question and as time passes it becomes even more and more valid. Doesn't it?
When l bought my Adams, l threatened my son to spend his inheritance on a yacht. He laughed and said "good on ya, dad!" So, l guess, it would not be much frowned upon if l spent another 10 or 11 boat dollars on a new engine. Ha ha.
However, if l could help it, l would not.
I have a small twin cylinder Vetus engine, shaft, and a twin folding prop. Fresh water cooled with heat exchanger. About 1988-89.
Well, one always could have more power but it is working fine, no hours known, who cares, starts and stops in a flash and the only problem was in the last five years a pair of glow plugs beside regular maintenance.
I mean regular.
It does not use any oil, does not smoke at all, white or black, so l guess it is ok inside.
If it carks suddenly it would be something major which, knowing diesel engines all my life, doesn't happen too often without warning.
This boat engines are tough little bastards, hard to kill, and they are seldom abused which is a main point in a life of any engine if regularly maintained. (change the bloody oil in every three months, no matter what!)
Parts availability is good, Vetus Maxwell in Sydney is represented by Fenquins and as far as l needed a part it was always available. Thou, l did not need much.
I would try to rebuild it.
If that would not be viable, l would shop around and go up a few horses. Yanmar most likely as my son doesn't minds spending his inheritance 
and l love my boat more and more day after day.
Maintain your engine, it might save your life one day! 
I have a MD21a penta, it's old but good apart from the oil cooler needs replacing. I cannot find one but told it can be changed. Anyone have an old one to sell or know how to convert to an external cooler.
I have a MD21a penta, it's old but good apart from the oil cooler needs replacing. I cannot find one but told it can be changed. Anyone have an old one to sell or know how to convert to an external cooler.
Lots of money to repower. So if you do, then you should make sure you treat your new investment properly. Diesels engine do not like running unloaded. Running a diesel engine (in neutral) to charge your batteries is very very very bad for them. And doing it at high speed doesn't make any difference. Diesel engines require pressure above the piston head to help expand the piston sealing rings other wise they will not keep the bore clean. Glazing of the bore will occur, not good. But don't take my word for it, speak to an engine rebuilder.
It's a package deal. Buying a new engine (or rebuilding an old) is just part of the solution.
