Which Marine Diesel

[bg9208]

I'm afraid that this is a bit of a portmanteau question to which answers are only likely to be generalities and I apologise in advance for asking such an open question but any guidance would be read and inwardly digested (Another column of the spreadsheet filled!).
I am looking, in the not to far distant future, to buy a GRP/Steel centre cockpit cruiser of around 12-15 metres built in the region of 1970-1982 and I am busy doing as much homework as possible, I tend to look upon major purchases as almost a military campaign.
There are a finite number of types and sizes of engines fitted to boats of this size and era and I would be very interested an any suggestions of which are the best bet, ie. reliability, still have availability of spares for rebuilds etc. etc - and which ones are absolute dogs, to avoided where possible.

[James S]

Mine had a Ford Mermaid from england that lasted 30 years....probably would still be fine If I had been more careful...I replaced it with another Mermaid..however its a totaly different animal.
I like slow RPM (mine is 2200max) and naturaly asperated.
If you looking at a heavy old cruiser its likely to be similar...

[never monday]

Originally Posted by bg9208

There are a finite number of types and sizes of engines fitted to boats of this size and era and I would be very interested an any suggestions of which are the best bet, ie. reliability, still have availability of spares for rebuilds etc. etc - and which ones are absolute dogs, to avoided where possible.

This is true, but any of these could have been replaced over the years. I would focus on the hull first, then evaluate which engine is in it.

[Bloodhound]

Chances are the absolute dogs have already been replaced. Replacing an engine is a really major expense. A well maintained truck diesel should be able to run at least 10,000+ hours (500,000 miles) before a rebuild (and 1,000,000 miles is pretty common) but marine applications are tougher so maybe 5,000 hours is more realistic - depends on use, and on sailboats use is unfortunately very intermittent (bad) which IMHO is probably the greatest cause of premature failure.

There's no way to assess how well an engine has been maintained without a maintenance log that details everything. So rather than worrying about absolute dogs, I'd be looking for (1) a maintenance log, (2) an engine with reasonable hours (probably the least important factor and certainly no guarantee of anything at all) (3) one that passes a full running inspection by a qualified marine diesel specialist (compression, injection, transmission, etc.) and (4) one with a horsepower rating matched to the boat's weight and shape (avoid underpowered, which is pretty common). Buying a used engine really is buying a pig in a poke 'cause you can't inspect all the innards, but the cost of a detailed engine inspection isn't that great and may save a lot of heartache later.

Just my $0.00002 worth .

[knottybuoyz]

I noticed your location is France so you might want to look into "Nanni" diesels.

www.nannidiesel.com

Sorry, no personal experience to offer with these engines.

[Stillraining]

FWIW

Unfortunately...even a great mechanic dosent have x-ray vision...and he is giving you his best educated guess..My engine tested out fine during sea trial with him aboard with one or two minor electrical deficiencies...after our first home sail I noticed the belts were not lined up like they use to be..once the belt tension was relieved I found the crank bolt holding the mail pulley on had completely backed out and the pulley fell off in my hands..
I know this is a good mechanic I dealt with him personally for over a couple weeks and he seemed very knowledgeable and professional and came highly recommended..but he could not see it and there was no indication of what was about to happen... if that pulley would have come off at full RPM it could have went through the bottom of the hull...fortunately nothing was damaged and I installed a new seal and reinstalled to proper tork with a new bolt.

My criteria would be

1) does it start easily ( means good compression )
2) does it smoke ( should not have any blue some white ok while cold but should go away) There should not be excessive black smoke under load either.
3) any visible oil or coolant leaks ( black dirty messy engine )
4) stays in temperature ( run it hard and find this out ) I would rather have deficiencies any of the above over this condition )
5) corrosion ( outside and inside ) inside is hard to gage but a good indication is to pull a hose or two look at the goose necks especially on the heat exchanger..how bad are they eaten away.. if it has internal zincs pull them as well and peer into all the cavities you have opened as best you can.
6) Pull an oil sample if you have doubts about maintenance ( but with out a prior bench mark or if they just changed the oil...it may be meaningless )

A good mechanic can get fancy but the above will do 90% of your diagnosis for you..and unless you know Supper mans phone number you wont find out much more..


Bottom line for me...If it runs solid it more then likely is solid.......untill it isn't.

[oldtom]

Originally Posted by bg9208

I'm afraid that this is a bit of a portmanteau question to which answers are only likely to be generalities and I apologise in advance for asking such an open question but any guidance would be read and inwardly digested (Another column of the spreadsheet filled!).
I am looking, in the not to far distant future, to buy a GRP/Steel centre cockpit cruiser of around 12-15 metres built in the region of 1970-1982 and I am busy doing as much homework as possible, I tend to look upon major purchases as almost a military campaign.
There are a finite number of types and sizes of engines fitted to boats of this size and era and I would be very interested an any suggestions of which are the best bet, ie. reliability, still have availability of spares for rebuilds etc. etc - and which ones are absolute dogs, to avoided where possible.

Hi stilltraing in the year of build 1970 -82 you find the UK Ford OR the 4-236 Perkins with the perkins being one of the largest no of Diesel built used in tractors,truck you name it to boats can still get parts a round the world water pump $150 ,main bears $70 etc check heat excharger fresh&raw waters sides,and check these fuel lines for rust pitting and replace