What is expected Genset Lifespan ? Onan 9.5kw

[Catapault]

Howdy,

What is the expected lifespan of an Onan Genset, assuming proper maintenance. (On a Yacht, salt water)

Looking at a boat with an Onan 9.5kw Genset with some 11,000 hours on it. It works now, but would like SOME feel for what it is going to cost in the future.

Unsure of maintenance history, but is in Charter, so prob 'ok'.

Comments on expected life of these devices on a Yacht ?


Appreciate any insights.

Regards

[Sailmonkey]

If used on a regular basis and serviced on a regular basis, I can see another 5-10k hours on it.

IMHO the number one killer of generators on boats is months on end at the dock without ever being used.


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[Zanshin]

I've got the same model (MDKBM) aboard my boat and it is a solid performer. 11K hours is pretty high and most likely it was run a lot overnight for A/C at a light load. If the engine was serviced regularly then it should run for a while a longer, but it is hard to estimate without having a pro look at the compression. The electrical components will most likely last longer than the mechanical parts.
I've found that my generator does go through more impellers than expected but it has reliably produced power whenever I needed it. For what it's worth - I have ~700 hours on it after 5 years, living aboard at anchor for 6 months out of the year.

[a64pilot]

With 11K its getting up there, if meticulously maintained and well run, it may be half life, or if not so meticulously maintained or well run, it may be run out.
On an older engine compression and oil pressure at idle when fully warmed up will tell a lot, you can make it idle and may have to temp install an oil pressure gauge

[marlinmike]

Not sure charter assures you of great maint, sometimes the opposite is true. I would agree with others in that the hours are up there, might want to factor in a replacement in a few years if it starts giving you trouble, but run it until it dies.

[sailon46]

I've got the mdkbl also got it out of moorings charter went in the 4 years I had it through fuel line problems had to soulder the fittings in Grenada and Curaçao to make it work. It was a hustle it now runs ok just shy of 10 k hrs.
Ernie on the Mary Jane

[seasick]

I would say that 11,000 hours is nearing the end of its useful life. If the genset is enclosed in a sound attenuating box it will tend to be in worse shape as problems with it tend to go unnoticed for longer periods.

A search of the web shows that few people expect more than 10,000 reliable hours out of these units.

I would factor in the cost of replacement and run it until it dies.

[Fishman_Tx]

Catapault,

I do power maintenance for AT&T and we use Onans as well as many others from 10kw to 1mw. 10k hours is a lot of use. One shouldn't worry about the alternator (generator portion) so much as the engine itself. The only problematic item for the alternator are the diodes breaking down from heat and use. These can be near impossible to find for older units if there aren't generic replacements available.

We have several Cummins powered gensets that are 40 years old but have only 2-3k hours on them, but even so, a regular maintenance program and logging what and when it's done becomes critical at this age to keep track of changes in the set. Good oil pressure is absolutely critical to the life of the engine. More frequent oil changes and maybe a change in the grade of oil used (i.e. 15w-40 change to SAE 40). Consult a Cummins certified engine shop (NOT ONAN) for the best way to keep up with the high hours. Does she use any oil? A preventative rebuild should be planned for in the future to change out rings, bearings, and seals and have the head worked over. The block should last near forever if the "wearable" parts are replaced in a timely fashion.
Don't wait til it dies mid-passage.

JMHO

Fish

[Catapault]

Thanks all !

Much appreciated

Regards

[evm1024]

One last thought is to get the oil and have it tested.

[Fishman_Tx]

Duh!!
Can't believe I forgot that! You can get a sampling kit for coolant, fuel, and oil for around $125 for lab analysis. They'll tell you everything you need to know.

[captainjay]

I manage charter boats. At 11,000 hours we would require an owner to replace it to stay in the fleet. While it may continue to run it will be finicky, leaky, noisy and require more "love" to keep running.