Diesel engines

[ghostlymoron]

I've often wondered why a boat engine needs so much attention. For example it's recommended by some authorities that the injectors are overhauled every few years despite having relatively little use during that period. I'd guess that a sailing yatch engine runs for about 50hrs a year which is equivalent to about 2000 miles (car equivalent). By contrast, my Merc has done 154000 miles and has never had any attention to the injectors or injector pump. Mind you having said that, the Merc does blow out some smoke on accelerating which suggests that the injectors need some attention now. I'm going to try an 'Italian tune up' as recommended by Vyv Cox before booking it in to the tuning bay.

 

[Sandyman]

I've often wondered why a boat engine needs so much attention.

I would have thought the answer to your question was quite obvious.

 

[ghostlymoron]

Sandyman,
If the answer was obvious, I wouldn't have asked the question.

 

[Rivers & creeks]

What's an Italian tune up?

 

[Stork_III]

What's an Italian tune up?

An italian tune up.

 

[theoldsalt]

Here we go again.

Why can't people on here be polite and sensible. I really do get fed up with unnecessary and quite rude responses to sensible questions.

And don't respond with "then leave the forum" beause occasionally I do get useful information and am able to pass on some of my knowledge and experience.

Shame the moderators can't filter out the idiots.

 

[emsworthy]

Sandyman,
If the answer was obvious, I wouldn't have asked the question.

My guess is that Sandyman was suggesting that if the engine in your old Merc failed to start or suddenly lunched itself mid-journey you might be mildly inconvenienced whereas on a boat the alternative modes of transport are a little more difficult to arrange.

Yes, I know you can always sail (if you've got them) but it probably wasn't in your passage plan to sail into your berth!

Just my guess though.

 

[snooks]

Shame the moderators can't filter out the idiots.

Oh but we can

Have you found the ignore button??

 

[macnorton]

An engine which is not regularly ran under high load will develop acids in the oil and will be full of carbon, this clogs the injector needles and makes the fuel "hose" into the chamber rather than spray as it needs to.
It is not expensive to have these checked and is preferable to having engine problems whilst at sea.
I use re-vite in the fuel to minimise this.a good thrash (Italian style ) will also help.

 

[Rivers & creeks]

Must be nice to have such insight, bet you can look right up your own arse

That kind of casual rudeness is unacceptable, you owe the OP an apology.

 

[sailorman]

My guess is that Sandyman was suggesting that if the engine in your old Merc failed to start or suddenly lunched itself mid-journey you might be mildly inconvenienced whereas on a boat the alternative modes of transport are a little more difficult to arrange.

Yes, I know you can always sail (if you've got them) but it probably wasn't in your passage plan to sail into your berth!

Just my guess though.

I would suggest that most modern cars, never, have the injectors serviced.
the problem with my 6 spd car is cruising rpm is about 2200, so running at 1/2 revs. to thrash it one has to keep / hold it in lower gears

 

[ghostlymoron]

Here we go again.

Why can't people on here be polite and sensible. I really do get fed up with unnecessary and quite rude responses to sensible questions.

And don't respond with "then leave the forum" beause occasionally I do get useful information and am able to pass on some of my knowledge and experience.

Shame the moderators can't filter out the idiots.

Oldsalt, I find this forum a mine of useful information generally and I'm prepared to accept the odd unhelpful response. Sometimes the abusive threads are quite entertaining. The response time on here is quite phenomenal unlike other forums I belong to where it is common to wait for weeks for a response. That's why I sometimes post non-boating type questions.
Still waiting for a sensible response to my origonal question though.

 

[macnorton]

Oh but we can

Have you found the ignore button??

Er! No. Where is it.

 

[snooks]

Sandyman,
If the answer was obvious, I wouldn't have asked the question.

How many miles has your merc done? in how long?

How many hours has your boat done? in how long?

Once a diesel is going, as long as it has fuel, air and water, unless there is a catastrophic failure it will keep going...Why do you think they don't turn the engines of Greyhound coaches off????

 

[Stork_III]

Er! No. Where is it.

Click on User's name, view public profile, user list, Add to ignore list.

 

[snooks]

Er! No. Where is it.

View someone's profile (click on their name) and when the next window opens up...you'll see a menu bar under their name that says "User Lists" in there will be "Add to ignore list"

 

[knuterikt]

I've often wondered why a boat engine needs so much attention. For example it's recommended by some authorities that the injectors are overhauled every few years despite having relatively little use during that period. I'd guess that a sailing yatch engine runs for about 50hrs a year which is equivalent to about 2000 miles (car equivalent). By contrast, my Merc has done 154000 miles and has never had any attention to the injectors or injector pump. Mind you having said that, the Merc does blow out some smoke on accelerating which suggests that the injectors need some attention now. I'm going to try an 'Italian tune up' as recommended by Vyv Cox before booking it in to the tuning bay.

With regards to the injectors I think the answer is that this depends on the engine - diesel is not diesel..
Modern car enignes as you (probably) have in your merc have a different type of injectors than the older type found in most marine engines.

Most cars have a service interval of xxxx km/miles or yearly.
Boat engines run with a effect of 80% most of the time, the load on a car engine is far less.
My car has a max rpm of 6000 but it rarely run over 2000 rpm
In the boat cruising speed is normaly only some 200-300 rpms under max...

"It's not running the engine that kills it - it is standing still that kills the engine"

 

[Tranona]

I've often wondered why a boat engine needs so much attention. For example it's recommended by some authorities that the injectors are overhauled every few years despite having relatively little use during that period. I'd guess that a sailing yatch engine runs for about 50hrs a year which is equivalent to about 2000 miles (car equivalent). By contrast, my Merc has done 154000 miles and has never had any attention to the injectors or injector pump. Mind you having said that, the Merc does blow out some smoke on accelerating which suggests that the injectors need some attention now. I'm going to try an 'Italian tune up' as recommended by Vyv Cox before booking it in to the tuning bay.

Nothing sure it is common advice, but already suggested many of the issues to do with engines in boats is related to the pattern of usage. Infrequent running for short periods without fully loading the engine is not good. Hard running is what they like which is why a regular Italian tuneup is a good idea.

 

[rob2]

Ther are, of course additional problems with the low usage of a marine engine. Diesel fuel doesn't go off like petrol, but most tanks will have fuel stored in them for months if not years. As an example, my boat has a 100 litre tank. When we started the trip home we decided it would be prudent to fill the tank - that was 2005 and I haven't topped up since. The fuel is old, probably has some condensation in it so vulnerable to the bug. It's been in there over several winters and it was a summer grade so it may be prone to gumming which can mess up the fine tolerances of the pump and injectors.

As already mentioned the frequent oil changes are to compensate for the fact that motoring on and off the mooring will not get it hot enough to stay clean and it will have condensation and acids in it.

Lastly, if I didn't do some maintenance on the engine on a regular basis, I wouldn't be up to speed should I need to effect a repair whilst at sea.

Rob.

 

[maxi77]

An italian tune up.

Interestingly it is also recommended by my local mechanic here to rejuvenate catalysers on cars where heat and high gas flow gets rid of various deposits. Certainly my dear old Thorneycroft engine ran a lot better after a few long motor sails