6000 hrs on volvo engine a concern?

davethedog

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Hi all, seen a nice sail boat we like and all sounds great and all the pics etc seem fine, but the only real concern i have at the moment is the engine has 6000hrs on it.

It is a VOLVO PENTA tmd31A and has had maintenance etc, such as new injectors, fresh water cooling but no major engine rebuild.

The boat is from 1989.

Is this a real concern, and something to fully expect to reduce a fair amount off the asking price for?

DTD
 
The asking price will reflect the hours on the engine - after all it is a known. It is only if you discover the engine is not what it is claimed to be that you stand a chance of getting a reduction based on new information.

6000 hours over 30 years is 200 a year - quite normal for cruising boats and maybe over half way through the life of the basic engine. If it is well maintained and does all the right things - starts, achieves near maximum revs under load, does not smoke or leak then little to worry about.
 
Mine is an MD 2020 year 2003 with nearly 5000 hours. New injectors 6 months ago & the tappets adjusted at the same time for the first time ever. 3 new exhaust elbows. 2 sets of seals to the water pump & a shaft once It is running like a sewing machine. Gets winterised every year prior to lay up,
If the one you are buying is in good nick & has been looked after ( mine does have good compression) you should be OK
 
Put it into perspective by comparing it with a vehicle. Not a particularly scientific comparison I know but vehicle engines are subject to constant and frequent extreme chages of power and are usually (always) goosed from stone cold while boat engines tend to be alloed to warm up and then run at constant revs (albeit often at high power - which is where a diesel is happiest)

OK, all very ballpark figures, but here's a comparison that I think stands some scrutiny:

My satnavs tell me that the average speed of my cars is about 35mph.Thus a thousand hours is 35,000 miles = 3000hrs per hundred thousand miles.

We all know that diesel cars can and often do easily run to 4-500,000 miles if well maintained. Ask your local taxi-driver...
The OP's 6,000 is (time wise) is thus the equivalent (ish) of a mere 200, 000 miles of road time, but at constant easy revs not being thrashed up and down gears all it's life. ie not all that much, imho.

I'd suggest that from mere running time alone and if properly oiled and serviced throughout it's 6000hrs it is probably a mid-life engine if even that and no reason per-se to assume it is anything but a good'un. If it starts reliably and cleanly, doesn't smoke or burn oil I'd be happier than if it were being touted as an unlikely 2,000hr engine in the same 20yr old boat. Bear in mind you're unlikely to get an engine sold to you as 6,000hrs if it isn't kosher (After all, who'd fudge hours to 6,000?) while a miraculous "2,000hr" engine in a 20yr old boat warrants (to me) very close examination...

Sure, marine engines have other specific issues, perhaps long periods of running at idle charging batteries that will eventually glaze the bores but that depends on the owner and his lifestyle of course and is difficult to factor in but can often be sussed by asking the vendor the right questions... Even so if it develops problems from that it is a very easy and not particularly costly thing to fix - a deglaze and new rings - which should exend life by several more years. Glazed bores says nothing whatsoever about the state of wear in the rest of the engine, and in a way might even be seen as a positive aspect in an older engine as it hasn't spent so much time developing power so the rest of is is less worn. Or am I being fanciful? I dunno!

Thrashed or brutalised engines are, I think, pretty rare in yachts (less so mobos) simply as it is rather hard to so - so given good maintenance they have a remarkable life expectancy.
A 6000hr engine in an underpowered mobo on the other hand...
 
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Imponderable; it might be good for another 10+ years or it might explode tomorrow. All you can do is look for evidence of correct maintenance and if possible have a test run to look and listen for clues.
 
If the oil has not been changed for a while you could send a sample off to make sure there is no metal in the oil. It will give you an idea of internal condition/wear. We use this process for large fridge compressors. The rest is down to viewing and listening and ease of starting/compression.
 
Just to add to the general consensus- my 30 year old boat is on its original engine and it runs perfectly. I knocked the seller down a hefty amount (the price of a new engine) and now feel a bit guilty about that.
 
Imponderable; it might be good for another 10+ years or it might explode tomorrow. All you can do is look for evidence of correct maintenance and if possible have a test run to look and listen for clues.
Indeed.
Any engine in a boat can go bang, I know people who lost relatively new engines.
The odds are obviously worse the older the engine.
But if one day you have to spend £6k on a new engine you will have a better boat. (by maybe £2k? £4k?)
With the boat I've just bought, the issued was also about the new engine being more powerful, quieter, smoother and indirectly cooled rather than just a like for like old/new comparison.
If the old engine is right for the boat, its age would not worry me so much.
 
Out of curiosity, if 200 hours engine use a year is typical for a sailboat how many hours are spent actually sailing? 200 hours at even 5kn is a fair distance every year.
 
The boat the OP is looking at is an offshore passage maker come liveaboard so would expect in some years the number of hours sailing would be pretty high.

The ratio of sailing to motoring really depends on the type of usage and location, but typical UK weekend sailing plus holidays is likely to average 150 hours motoring and 250 hours sailing (generous 40 days of 10 hours each).

My charter boat in the Ionian (20+ weeks a year) where not much wind averaged just under 500 engine hours a year over 7 years.
 
Out of curiosity, if 200 hours engine use a year is typical for a sailboat how many hours are spent actually sailing? 200 hours at even 5kn is a fair distance every year.
As ever, depends a lot on how you use it. A lot of our boat engine hours are not actually travelling anywhere near 5 knots. For example, a day anchor to anchor will typically put engine on before starting to lift anchor, so may not even be in gear for first 10 minutes or so until anchor up, clean and on board. Then perhaps 5-20 minutes pooling slowly to get out of anchorage. Reverse on return so 40-60 minutes each day doing under 2 miles.
Perhaps slightly less extreme sailing to/from pontoons, but still tend to start before start casting off ropes, and slow poodle out of harbour. 100 days sailing and get 50-100 hours even with sailing everything in between.
 
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