New to Diesel Engines, Advice me!

[mil1194]

If a diesel starts easily according to the expected procedure (not all have glowplugs) and the oil pressure picks up to spec within a few seconds there is nothing fundamentally wrong with it. If it revs up, out of gear, happily to the rated max rpm without sounding like a bag of spanners being shaken, and without immense gouts of smoke or steam, thats even better. Hard to check much more without a proper test run to look at operating temperature and so forth which need a more sustained run. Oil can be black but not thin or sludgy, no obvious oil or fuel leaks and coolant system should be filled to spec and stay there.

A basic diesel is a far simpler and forgiving beast than petrol, give it clean fuel and enough air and it runs, pretty much end of, its not fazed by some damp in the area. But, a very modern diesel with electronic common rail injection and emission control systems is just as complex as a modern petrol engine, simply in a different way.

+1

 

[mil1194]

Well done Andrew! Finally some real words of wisdom. Agree with everything you say.
If it starts easily from cold it's probably fine.

ps
We know there are idiots on this forum. It seems they all showed up at the same time today!

+1 - most sense I've seen on some of these boards in a long time!

 

[Andrew_Fanner]

<takes bow>

Should I have added something about petrol engines being the love child spawn of Beelzebub and a tax collector just to fit in?

 

[rafiki_]

<takes bow>

Should I have added something about petrol engines being the love child spawn of Beelzebub and a tax collector just to fit in?

No, but you might add that the lazy V8 petrols, are really only designed to operate between 1000 and 2500 revs. The cars they propel cruise at 70 mph at less than 2000 revs. Only the very recent OHC and 4V V8's are happy for extended periods above 4000 revs.

To countre, there are maintenance things on diesels. Mine have cam drive belts that need changing at 5 years. Belt failure can be catastrophic on any engines. Coolant systems for petrol and diesel can only really be checked under load, so a quick buzz up and down the revs would not show this.

However, diesels on anything ever 25 foot ish are prefereable for UK/Eu use due to fuel efficiency, and availability. My 33 footer does 6-8 gph at WOT, with petrols if would be nearer 20-30 gph.

 

[Rocksteadee]

I am currently looking into the transition from petrol head to diesel.
In the form of the Volvo Penta TMD40
They are 30 years old and at present know nothing else
So are they a good engine, reliable, any know quirks, problems?????????
Many thanks in expectation to the hundreds of replies to come flooding in

 

[hlb]

Well done Andrew! Finally some real words of wisdom. Agree with everything you say.
If it starts easily from cold it's probably fine.

ps
We know there are idiots on this forum. It seems they all showed up at the same time today!

Not sure I totally agree. Some engines just smoke, especially on start up.

Bad starting may just require an injector service, which may also cure the smoke.

 

[rafiki_]

Not sure I totally agree. Some engines just smoke, especially on start up.

Bad starting may just require an injector service, which may also cure the smoke.

Agreed. Mine smoke at idle, but clear as soon as the throttles are opened. Does not cause me any problems, and starting is fine.

 

[BartW]

Hi everyone!

We have been boating on Ribs and Motor Cruisers all using petrol outboard engines since 1996! So I feel quite confident about any make and model of outboards and their typical problems and how to rectify them.

But now we have been looking for some fishing boats (Arvor, Quicksilver etc.) and some use Diesel Engines i.e. VW, MerCruiser, Cummins etc.

Because all the boats which we are going to view are pre-owned packages, I appreciate if you could help me on this.

What do we have to look for in a diesel engine? what could go wrong and what usually goes wrong say after 2-3 years?

Any advice on this is very much appreciated.

when you're looking at a fish promenade boat, then you're probably not after the maximum performance nor speed versus weight.
and then you are in a interesting area for diesel engines,
heavy and solidly buyld lumps running in a very relaxed mode.

brands to look for are Yanmar, Nanni (Kubota), or Volvo Penta.
personally I would avoid mercruiser cummins diesel, but some on here will not agree on that.
can't give you any technical advice, appart from having a specialist / surveyor looking at it before you buy, and stay with a main brand (one of them mentioned above) for support, servive and experience reasons.

put Beneteau on your list; the bene 620 with nanni diesel is a nice package and will work forever !