Anything wrong with rebuilding?

[Saltyhog]

Originally Posted by JOHNMARDALL

Whatever you do yourself, it will still be an old engine, with another part just getting ready to break or freeze up and let you down. Re-manufactured could be all right, if you thoroughly research the company doing it and if they have a suitable engine in stock, but if you don't want to spend your time being an engine mechanic, I recommend going straight to what will probably be the end of the process anyway, and getting a new engine now. Yanmar and Beta are the companies to talk to for sailboat engines and your main concern should be finding an engine of the required power that fits your engine beds.
Anytime I don't take my own advice and spend time and money repairing old equipment, I end up regretting it, especially fiddling with ancient diesels.
Good luck
John Mardall
Vetus Maxwell Group

This! Although you'll find plenty of folks chiming in on how they rebuilt their engine in their cockpit for $1000 in parts, the truth is that it's rarely that simple or cheap. Finding the (correct) parts for your particular engine is the first and often overwhelming challenge. Even engines of the same model will have different revisions with different BOM's (Bill Of Materials), and so the new part that is listed to fit your engine may or may not fit. What do you want to do: Become an expert on your particular engine's build history and it's nuances of part availability, or do you want to get sailing? Old engines are old and use old tech. Just on soft parts alone, the seals on modern engines are far better designed and use better materials. If you need a reliable engine you can count on for service in out of the way places, just buy new. If you are sailing local, all you really need is an engine that starts and runs today. Keep your old engine and fix as needed.

[tmason]

I got a new Beta 30 for 10K four years ago, also Kubota based, but based on the D1150. Bulletproof and easy on fuel. It replaced a M25. Still not cheap, but you know what you've got. Otherwise DIY so you know what's in there. If you go the new engine route you will have to go to a 2" exhaust system as the new engines are set up with 2" risers to satisfy some recent reg. or other- extra expense.

Good luck.

[tmason]

Sorry, that is a D1105

[wannago]

I've taken engines apart and put them back together again. And they've still worked when I was done.
But for a proper rebuild, you have to be proficient in using a micrometer to even get the correct parts ordered. Bearings and rings have to fit pretty exactly, and should be checked with plastic gauge.
Without understanding how to do this correctly, you can pretty easily sink $500 to $1000 dollars into parts, hours of work into taking it apart and putting it back together again, and have an engine that runs fine for 100 or so hours, but it really in worse shape than you started and dies pretty quickly after that...
You'll need a bunch of tools that just aren't that common, ring compressor, valve spring compressor, accurate torque wrench (assuming you've very familiar with how to use one of those), and an engine stand, at least.
If you wanted to go cheap, DIY, but aren't confident you can do this to machine shop standards, just swap the rings and hone the cylinders. Once you start replacing main bearing, you have to make sure everything fits, to like .01 inches or so (probably better), or your just wasting time and money.

[Cheechako]

As I mentioned earlier, nothing wrong with rebuilding if the engine isn't such high hours that the peripherals like the injector pump etc aren't going to last.. But for many people it would be worth having an real mechanic rebuild the short block and head. There is a learning curve in rebuilding. I would think a mechanic could do a basic overhaul on that little engine for.... $1500-2000 Assuming you take him the basic block and destall/install yourself.
Could you do it? yes, Should you do it? Maybe not.

[a64pilot]

Originally Posted by Terra Nova

Though I agree that there's no good reason not to overhaul, it is common knowledge that an overhauled engine is NOT better than (nor equal to) new.

Any engine that I have overhauled is better than it was new,
Reason is I hold tighter tolerances and essentially " blueprint" the motor by CCing the head and having the crank balanced and balancing the pistons and rods myself. If I do the head I clean up and match the ports and do a three angle valve job, install bronze valve guides and ream to fit, but I no longer have the facilities to do valve jobs, so I would out source that.
Now this isn't common and in truth may be of little value on a relatively slow turning Diesel, but I maintain if done right by a knowledgeable person an overhaul is better than new.
Even the gaskets you get can often be better than OEM.
As with most things, a Craftsman who isn't on the clock that can spend extra time, can often produce a product that is superior to something mass produced.

Many years ago when I built drag bikes, I honed each cylinder to give 1.5 thousands clearance to the piston that was going into that bore, as opposed to honing to a set size for instance. You don't get that in mass production.

I do it as I enjoy it, and get a sense of satisfaction in making it as good as I can.

[Cheechako]

Well.... I think for the typical "rebuilding" of anything... or maybe "refitting" of boats too, or Vintage cars, They seldom come out as good as original. Of course there are people who are detail oriented enough and fastidious enough to do it near perfectly, but for the average layman... no. Many marine diesel are not worn out though, they get rebuilt at very low hours. Probably because of lack of use, or short term use as much as anything. SO when you rebuild one of these, many components like the cam, rockers etc are likely in very good condition, although the rings may not be. So there's that thought also.

[bcboomer]

Based on my own experience, rebuild it yourself if you have a place to do it. My only concern would be finding a machine shop that has lots of experience with that exact engine. Otherwise they may not get the correct clearances on things (like pistons).

[bcboomer]

One more thought.
If only 1 cylinder is down, maybe you just have rings stuck into the grooves due to dirty oil and carbon build up. I've seen a number of gasoline engines rejuvenated to perfectly acceptable performance by running a strong engine flush solvent.
I even did it successfully running straight ATF under a light load for a couple of hours then changing oil and filter.
For the price of a couple of filters, oil and a can of whatever oil solvent is available you might save a lot of money.

[Sailmonkey]

Originally Posted by bcboomer

One more thought.

If only 1 cylinder is down, maybe you just have rings stuck into the grooves due to dirty oil and carbon build up. I've seen a number of gasoline engines rejuvenated to perfectly acceptable performance by running a strong engine flush solvent.

I even did it successfully running straight ATF under a light load for a couple of hours then changing oil and filter.

For the price of a couple of filters, oil and a can of whatever oil solvent is available you might save a lot of money.

How about an "Italian tuneup"? Maybe even with some power service or similar in the fuel.

[captlloyd]

Yes you can rebuild your engine and save tons of money. Good advice to find a tractor shop that does rebuilds if you do not want to take it on yourself. Or you might find a decent mechanic on Craigslist under ''Services''. Then you provide the parts (very available for your engine) and he does the work, or better yet, you work with him and learn. One thing I have noticed on CF, the folks with lots of money discourage doing and learning on your own, they just throw money at the problem. They also say you don't get the same quality, but that is not always true. Sure, if I have the money setting in the bank I buy a new engine. And keep my hands clean. That is just not me.

[Stu Jackson]

Originally Posted by bcboomer

One more thought.
If only 1 cylinder is down, maybe you just have rings stuck into the grooves due to dirty oil and carbon build up. I've seen a number of gasoline engines rejuvenated to perfectly acceptable performance by running a strong engine flush solvent.
I even did it successfully running straight ATF under a light load for a couple of hours then changing oil and filter.
For the price of a couple of filters, oil and a can of whatever oil solvent is available you might save a lot of money.

Pretty good thinking there. ^^^^^^^^^^^^^^^

Engines 101 - The BIGGEST & BEST collection of M25 Series Universal Engine Information on the Internet, plus some M35, too

Diesel Engine - c34.org

[CoolBeans]

Having rebuilt several automotive engines and doing a serious refresh of my atomic 4 in my sailboat. . .my own experience is that if you can get your little diesel rebuilt (with warranty I'm assuming) for $2000, I would go that route.

[Terra Nova]

Originally Posted by a64pilot

Any engine that I have overhauled is better than it was new,
Reason is I hold tighter tolerances and essentially " blueprint" the motor by CCing the head and having the crank balanced and balancing the pistons and rods myself. If I do the head I clean up and match the ports and do a three angle valve job, install bronze valve guides and ream to fit, but I no longer have the facilities to do valve jobs, so I would out source that.
Now this isn't common and in truth may be of little value on a relatively slow turning Diesel, but I maintain if done right by a knowledgeable person an overhaul is better than new.
Even the gaskets you get can often be better than OEM.
As with most things, a Craftsman who isn't on the clock that can spend extra time, can often produce a product that is superior to something mass produced.

Many years ago when I built drag bikes, I honed each cylinder to give 1.5 thousands clearance to the piston that was going into that bore, as opposed to honing to a set size for instance. You don't get that in mass production.

I do it as I enjoy it, and get a sense of satisfaction in making it as good as I can.

It is irrelavent because this is not what the op (or anyone else) will get with an overhaul.

[a64pilot]

Originally Posted by Terra Nova

It is irrelavent because this is not what the op (or anyone else) will get with an overhaul.

Why? Anyone who will do their own bottom job or their own teak, why would they not do their own overhaul?
If for example it s worth anything my boat is being pulled next month for me to pay someone else to do a bottom job, but I would never pay for an overhaul.
Why? Because the overhaul is likely less work, and yet way more money in labor if you pay someone else.
A small Diesel is really very easy to overhaul, especially if it has wet liners. Anyone can use plastigauge, a micrometer does require a little practice using the vernier scale, but plastigauge, if you have good eye sight, your in.
The head you take to a shop, as you do the injectors.

I am pretty sure Sailor Chic overhauled hers in the boat, or at least with very little assistance and few if any special tools, and did so for a whole lot less than a repower.