Small Diesel engine life-span - 120hp and 165 hp

[wildwords]

Hi guys

Eventually we have narrowed our search to a few possible vessels around our budget, but the reliability and life-span of the diesels is a bit of a question. If we go for a diesel we want it to last the 200 -300+ hours we will put on it annually for a minimum of 5 years. Of course we will maintain it to the letter etc.

If anyone has any experience as opposed to pillow talk on the engines below and their likely realistic life-span, their opinion would be greatly appreciated.

Engines

1998 Yamaha ME370STI 165HP (800) hrs done - driving a 7.4m redbay

2002 Mercruiser 1.7dti 120 hp (400) hrs done - driving a 6.5m humber

2006 Volvo D3 130 hp with 30hp chip ( 400) hrs done - driving a 6.3m humber

2007 Mercruiser 1.7dti 120 hp ( 200 ) hrs done - driving a 6.3m parker

Many thanks

Emo

[willk]

In his article (somewhere on here) John Price proposed that the average lifespan of a diesel inboard was c.1500hrs, depending on useage etc.

Your application will involve very low revs for a lot of the time and I think this should squeeze a few more hours. In fairness, he was suggesting 1500hrs as the time they started to have major failures.

[Mollers]

It's a bit of a 'peice of string' question. A lightly loaded, meticulously maintained deisel could go on practically forever. I had a 2.5ltr BMW that did 300k miles on regular servicing and a set of heater plugs.

However, a 1.7ltr lump in a 6.5m rib is going to be far from 'lightly loaded'. I'd go for as big a lump as you can sensibly find. A lazy big deisel probably wont burn as much fuel as a flogged tiddler.

[doggypaddle]

Originally Posted by willk

In his article (somewhere on here) John Price proposed that the average lifespan of a diesel inboard was c.1500hrs, depending on useage etc.

Your application will involve very low revs for a lot of the time and I think this should squeeze a few more hours. In fairness, he was suggesting 1500hrs as the time they started to have major failures.

Surely that incorrect? 1500 hours? thats equivalent to 45,000 miles in a car! Most diesels I have worked on wouldn't be considered fully run in at 1000 hours. our hire boats used to clock up over 1000 hours a year, and my mates tractor clocked up 12000 hours in 4 years,
The generator outside iceland in Monmouth ran for a year continuously,
thats 8000 odd hours!
in my plant experience we found heavily used plant engines generally got tired at 10-20000 hours, and generally got run out of oil by hirers, so were murdered rather than popping their clogs from naturel causes

wern't the lister generators sold to trinity house specced to run 52,000 hrs(six years) continuous ?

obviously engine load makes a big difference, and boat engines tend to be heavily loaded, but conversley in a vehicle application its the stop start that wears them out, marine engines tend to be more constant speed use and stopped/started less?

[doggypaddle]

i wonder how many ways diesel will be spelt by the end of this thread
we have 2 ways so far

[willk]

Personally, I have no idea if it's correct. I would stress that we're not discussing gp diesel engines, but rather small marine units. These are generally producing much more power than the original design allowed for. I'm guessing that the leg is included in the equation.

The opposite would be a 1500rpm "continuous/prime" genny, designed to run for ever...

Think about the 1500 hours though. What is the life expectancy of a small marine diesel, or indeed, medium sized outboard in hours?

100 hours a year for 15 years....?

[HUMBER P4VWL]

No actual experience, however willis estimates sound realistic. Two factors to also think about when estimating lifespan:
1. Boat engines generally float about on salt water as opposed to generators in dry sheds.
2. Like cars. 1000 hrs could be done oner 2 years or 10 years. The former is kinder due to less engine use at cold.

[willk]

Originally Posted by HUMBER P4VWL

however willis estimates sound realistic

Not my estimate but rather that of John Price.

Maybe not the day to call me willi either, thnx

http://news.bbc.co.uk/2/hi/americas/8535618.stm

[Erin]

Originally Posted by doggypaddle

i wonder how many ways diesel will be spelt by the end of this thread
we have 2 ways so far

Depends if gArf joins in

[Mollers]

Originally Posted by doggypaddle

i wonder how many ways diesel will be spelt by the end of this thread
we have 2 ways so far

Duckin Fyxlexia is a Bsatrad.