Cost of Overhaul

[Paradise1]

I'm looking at buying a boat with John Deere 6.8L that has 3000 hours on it. Anyway, the boat is otherwise in amazing condition, and my wife loves it, but she wants the JD overhauled. I know about all the arguments about JD and other engines (Cummins, Yanmar, etc.) reaching 10,000+ hours. This statistical data means absolutely nothing to my wife, and she is willing to walk from the deal if it is not overhauled. My question is not whether the JD needs overhauled, but how much will it cost me? I have no idea... I want the boat!

[rbk]

Most likely doesn’t need any work outside some bolt on parts being replaced IF it has been properly maintained. Check the heat exchanger, water pump(s), loft pump, injection pump, hoses, exhaust, compression etc for leaks, corrosion and general neglect. Do and oil sample and see how it fires from cold. If any are questionable and you get the boat you can replace those parts yourself rather easy (even with little mechanical experience. At that point adjust the top end. If you really have to do an ‘overhaul’ just do the top end. Unless there is known damage (prolonged submersion) or oil sample shows major wear, the bottom end is barely broken in yet and you’ll easily be able to double your hours without any major work. Only reason I suggest the top end is clearances don’t get adjusted, too many additives, old coolant, bad fuel and dirty engine compartments can carbon and gum up valve seats and clog galleries; it’s a fairly easy job that you can do mostly yourself and reduce labor costs by doing removal/install yourself and take the head and valve train into almost any automotive shop and they’ll grind and set everything to spec for you to bolt it back on at a very reasonable cost. I don’t know your engine so take the above as it is.

[Lepke]

A good mechanic doing a compression test or better yet a leak down test can give a very good indication of the engine condition.
Having the engine rebuilt in place could be 10 grand. Considering the usual hours put on a recreational engine, you could buy the boat, use it for several years and find the engine in almost the same condition as when purchased.
I realize "you can't tell a woman anything".

[Hesti]

Well, an overhaul is not a rebuilt. An overhaul is what a good mechanic makes it to give again years of trouble free service. Things like impellers changed, pump bearings checked or pumps replaced, alternator brushes replaced, ... ... ...

There may be an inspection manual for that engine, a big inspection should already take care of most of the points that need taken care of and then a bit of brainstorming on "beyond".


And: Have the fuel tank cleaned! And the engine feet and bearers checked. And the prop shaft, bearings and seal checked and if needed done. Seacock and cooling water hoses may need attention ... ... ... .


If looked for, you will likely be able to invest an x kUSD sum for added peace of mind and that is your overhaul.


:-)

[boatpoker]

All the various interpretations of "overhaul" leave you a very wide latitude.
Filters, fuel lines, new flashy blue silicone hoses and fresh paint ... there .... done

[Compass790]

Originally Posted by boatpoker

All the various interpretations of "overhaul" leave you a very wide latitude.
Filters, fuel lines, new flashy blue silicone hoses and fresh paint ... there .... done

Yea! good approach. Think of it as 'makeup'

[skipmac]

Originally Posted by Compass790

Yea! good approach. Think of it as 'makeup'

[skipmac]

Originally Posted by boatpoker

All the various interpretations of "overhaul" leave you a very wide latitude.
Filters, fuel lines, new flashy blue silicone hoses and fresh paint ... there .... done

Exactly. Overhaul doesn't mean take the block apart and install new main bearings, rings.

And there is an argument for "overhauling" an older engine. When I bought my boat with a 30 year old Westerbeke (which turned out to be a Perkins 4.154 with red paint and a huge markup on the parts). The engine had 2200 hours and ran like a top so didn't feel like it needed a rebuild. So I stripped it down to the bare block and installed:

- all new cooling hoses for engine, transmission, and oil.
- new alternator and wiring
- took the starter to the shop and had it overhauled.
- rebuilt the injectors
- new raw water pump
- rebuilt fresh water pump
- New dual Racor fuel filters
- pulled the fuel tanks and had them steam cleaned.

To me this removes 99% of the potential failure modes and is almost as good a new engine.

[Paradise1]

Okay, you good people are supporting the logical premise of my wife (which is really not helping me - regardless of how right you are!), but to make matters worse, to Skipmac's point, there are other important items beyond an engine "overhaul" that may need rebuilding, replacement, overhaul, etc.

I surrender and get what you are all are saying. However, to my wife's cynical point, she does not want to rely on finding an "honest and competent" surveyor in an unfamiliar area buying a boat with high hours, but would rather just negotiate an engine top overhaul (and now other "Skipmac elements") into the price and start off boat ownership with things taken care of... Sounds to me like $10,000 may be a good starting value for these items? I get that this may not cover 100% of it, but would be a good effort towards mitigating issues...

By the way, I love the idea of clarifying the "obvious for the oblivious!"

[skipmac]

Originally Posted by Paradise1

Okay, you good people are supporting the logical premise of my wife (which is really not helping me - regardless of how right you are!), but to make matters worse, to Skipmac's point, there are other important items beyond an engine "overhaul" that may need rebuilding, replacement, overhaul, etc.

I surrender and get what you are all are saying. However, to my wife's cynical point, she does not want to rely on finding an "honest and competent" surveyor in an unfamiliar area buying a boat with high hours, but would rather just negotiate an engine top overhaul (and now other "Skipmac elements") into the price and start off boat ownership with things taken care of... Sounds to me like $10,000 may be a good starting value for these items? I get that this may not cover 100% of it, but would be a good effort towards mitigating issues...

By the way, I love the idea of clarifying the "obvious for the oblivious!"

First comment, as others have mentioned, 3000 hours isn't high hours for a heavy duty diesel. 3000 hours is roughly equivalent to 100,000 miles or so. Commercial trucks can expect several hundred thousand miles on an engine.

I would have an ace mechanic check oil pressure hot and cold, compression, leakdown, and maybe even an oil analysis. Also look at the condition of the exhaust system, mixing elbow, manifold, etc. If all looked good I would just do the externals and leave the block alone (assuming the wife agrees). That would get the cost down to a couple boat bucks instead of ten.

[Compass790]

Now that I've stopped laughing possibly best bet is to ring up a place that overhauls them & get a price so you know what to aim at.
Maybe you should get "she who must be obeyed" to do the negotiations around price armed with that information.
Doesn't sound like wether the engine is fine or not is going to be a factor so then work with what you can.

[masonc]

Originally Posted by Paradise1

I'm looking at buying a boat with John Deere 6.8L that has 3000 hours on it. Anyway, the boat is otherwise in amazing condition, and my wife loves it, but she wants the JD overhauled. I know about all the arguments about JD and other engines (Cummins, Yanmar, etc.) reaching 10,000+ hours. This statistical data means absolutely nothing to my wife, and she is willing to walk from the deal if it is not overhauled. My question is not whether the JD needs overhauled, but how much will it cost me? I have no idea... I want the boat!

3,000 hours is just broken in for a well kept diesel. I sell generators, and see 20,000 hour generators come up for sale. My little Yanmar 3GM30F has 5,000 hours and going well.

[kmacdonald]

The JD 6068 is a 15000+ hour engine. It has cylinder liners so can be rebuilt to like new. As diesels go, they are relatively inexpensive to rebuild. They are in a lot of tractors.

[Tillsbury]

You're not going to get 10k taken off for a spurious overhaul of a working engine. But if that's the number you would like to put out there, it will be plenty.

I second the plan above of telling a good engineer to replace all the hoses/pumps etc and do pretty much everything reasonable that can be done to make the engine look sparkling. That will be "overhauled", as much as the engine needs I'd say. A budget of 2-4k would be more than enough.

[jimbunyard]

If there is no problem now, to 'overhaul' that particular engine at 3000 hrs is ludicrous. Not to mention that there is a reasonable probability that an issue will be created in the misguided attempt at 'preemption' of future problems.

It is only half tongue-in-cheek that I suggest you learn to lie, and sock away the money saved for a real future problem...