Engine hours

We are looking to buy our first trawler and I have a question regarding engine hours.
I see engine hours low and high, I look to see how well maintain an engine is, but still unsure how many hours is to much. And how long will an engine least before requiring replacement of to be rebuilt.

Thank you
Henry

That's like asking how long is a piece of string!

Well maintained diesels can go 10K hours before a rebuild. Badly maintained or totally ignored engines can need major work under 2K hours.

Look for meticulous record keeping, especially if the work is mostly done by the owner.

Greetings,
Mr. hf. Welcome aboard in case I missed you. Engine life is dependent on numerous factors. Everything from proper break in, from new, to proper storage procedures as well as brand of engine as well so it's difficult to quantify life expectancy as X number of hours or Y number of gallons of fuel. The only anecdotal information I can pass on is I've heard from several sources a properly maintained Lehman 120HP (380cu. in.) should last in excess of 12,000 hours.

Henry


A base engine may last a long time, but not the stuff bolted on to the outside like water pumps, heat exchangers, exhaust elbows, after coolers, alternators, belts and hoses. It is failure of these hang ons that ultimately do most of our engines in, like one overheat caused by a water pump failure. Don't forget about the importance of correct propping for long engine life if you have a vessel that routinely runs above say 60% power.


Enjoy your purchase and maintain by the book for a happy boating experience.

hfmckevitt said:

We are looking to buy our first trawler and I have a question regarding engine hours.
I see engine hours low and high, I look to see how well maintain an engine is, but still unsure how many hours is to much. And how long will an engine least before requiring replacement of to be rebuilt.

Thank you
Henry

Click to expand...

There are a couple of threads on this subject that you can find if you search.
While 10 to 20K hours is always a goal, I recall not many of the folks here have anywhere near that many.
Mine (120 Lehman) is still a 4 digit midget at 4600+.

Remember that any one of us can be just an "oops" away from disaster.

I attended the Bob Smith workshop a few weeks back. Bob stated on more than one occasion, during the class, that a well maintained Ford Lehman engine could easily run in excess of 20,000 hours. The key is WELL MAINTAINED!

I think Sunchaser made an important point reference loading. If the boat you are looking at has highly loaded engines, your diligence is even more important. A Lehman is generally a lightly loaded slower turning diesel. They a not very heavily stressed running in the load range that they are installed in. Marine age is another consideration. Like he said, it is the accessories on the engine that wear out, not the engine itself, that can fail and cause bad things to happen. Not so coincidently, the less loaded engines do not have a lot of these accessories...i.e. Turbos and after coolers. So give us an application, boat married to engine, and we will likely be able to help you a bit more.

I bought a 2001 boat with 300 hours. Guess what piston liners do when they are not running? RUST.
Surveyed fine then cost me 30,000 when things started failing. Diesels like to be run and maintained. The engine manual will list hours & time intervals for cooler maintenance, valve adjustments, oil/zincs...

I would look for a moderately-used (hours) engine, not very low (as in under 50 hours per year) nor high for its age. Would want one having at least annual servicing. ... This is not an expert opinion, but it's the way I feel. My engine runs about 125 hours a year and is professionally serviced annually.

As an addendum to my previous remark, upon considering a used boat, I'd want to look over its log to see how often the boat was operated and maintained. No log? Uh, oh.

markpierce said:

As an addendum to my previous remark, upon considering a used boat, I'd want to look over its log to see how often the boat was operated and maintained. No log? Uh, oh.

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Further to what Mark said, anyone who is diligent with a log will usually have lots of receipts to back up logged maintenance and repair entries.

Hawgwash said:

Further to what Mark said, anyone who is diligent with a log will usually have lots of receipts to back up logged maintenance and repair entries.

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Got the receipts onboard. Nevertheless, will the cost of maintaining a boat scare away potential buyers?

markpierce said:

Got the receipts onboard. Nevertheless, will the cost of maintaining a boat scare away potential buyers?

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How potential is a buyer that hasn't crunched numbers by the time he starts asking to see log books?

Baker said:

So give us an application, boat married to engine, and we will likely be able to help you a bit more.

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This sounds like a fun game! I'll start...

1977 34 Californian LRC with twin Perkins 4.236 85 hp naturals. 38 year old engines with 3000 hrs. No history past 7 years/900 hrs ago when I bought the boat. How long will they last?

markpierce said:

I'd want to look over its log to see how often the boat was operated and maintained. No log? Uh, oh.

Click to expand...

I bought mine without logs or history, but felt comfortable with the engine reputation and the engine survey which I have come to learn was deficient. Even so, they have been as reliable and efficient as they are loud and shaky.

"I bought a 2001 boat with 300 hours. Guess what piston liners do when they are not running? RUST."

True , however IF the owner had followed Da Book and had the necessary work done for being out of service , this need not happen.

Too many folks use the owners guide , rather than paying for the service manual,,DA Book,,
to discover the required PM and service requirements.

Best $100. or so you can spend on the engine.

At least on the boats I have looked at over the last year or so the "trend" seems to be less and less detailed logs for anything.

Doesn't mean the work has or hasn't been done--just no log to show what & when.

1971 C&C Custom 37' FD with Perkins HT6-354, five ring version rebuilt at 20,000hrs.

It had a little bit of slap in one piston and would have lasted much longer but I had nothin' else to do that winter.