Engine - refurbish or replace ?

[K2MSmith]

My original 1982 M25 engine still runs reliably but it obviously is not a new engine. The paint is peeling off and the diesel mechanic recommends a general refurbishment at some point. I just had alternator rebuilt to fix a tach problem - that was over 800 (but also included adjusting stuffing box).

When I bought the boat I was a bit naive as far as engine replacement costs (especially in this area). I knew the diesel might have to be placed eventually. no big deal how much could a 25 hp diesel engine possibly cost to replace - 5k-10k ?. . Well, I was off by orders of magnitude. A new Yanmar 30 repower with new transmission, panel and controls is going to run about 20-25K depending on prop, shaft etc.). that's almost what I paid for the boat. Not prepared to do that right now.

So my options are :

1) maintain the engine that I have and keep it on life support and make a decision in a year or two (or 3) - maybe even electric or hybrid an option at that point

2) spend money to refurbish (or rebuild ) the engine I have. I can't wait to hear how much that will cost.

3) just get a new engine eventually

Honestly, I don't want to do 3) yet as I've only had the boat less than a year and it still runs fine - budget considerations also put that out of contention if it really costs 20-25K.

Would appreciate any thoughts from owners who have gone through this scenario....

 

[Frank Langer]

Can you give us a bit more information on why your mechanic feels it needs refurbishment? How many hours on it, if you know. How was it maintained by previous owners--oil changes, valve adjustments, etc. Diesel engines seem to last best when they are run at normal operating speeds regularly, for long enough to get to operating temperature, burn off any excess carbon, moisture, etc. Is it showing any symptoms--clouds of black, blue or white smoke, or hesitating and stalling or any other abnormal sounds?
I have learned to be a bit skeptical of mechanic's advice, and usually want a second and third opinion, though there are some very good and honest professionals as well. Maybe you could ask around in your marina as to the reputation of your mechanic, and any others that you could have take a look and listen to the engine, before you decide what to do.
Keep us posted on what you find.
Frank

 

[K2MSmith]

Can you give us a bit more information on why your mechanic feels it needs refurbishment? How many hours on it, if you know. How was it maintained by previous owners--oil changes, valve adjustments, etc. Diesel engines seem to last best when they are run at normal operating speeds regularly, for long enough to get to operating temperature, burn off any excess carbon, moisture, etc. Is it showing any symptoms--clouds of black, blue or white smoke, or hesitating and stalling or any other abnormal sounds?
I have learned to be a bit skeptical of mechanic's advice, and usually want a second and third opinion, though there are some very good and honest professionals as well. Maybe you could ask around in your marina as to the reputation of your mechanic, and any others that you could have take a look and listen to the engine, before you decide what to do.
Keep us posted on what you find.
Frank

I need to talk to mechanic and get more details. I don’t have any exhaust smoke . There is no Hobbs . Previous owner maintained the boat well but I have no records from him other than a new exchange system was put in a few years ago . There were cooling issues but that seems to be rectified . The temp is stable and runs in the middle of the range on gauge . Given the reliable wind conditions and the fact that the boat was used exclusively in the bay ( it may have never gone offshore) , most likely the engine hours are low for its age. ( 38 years ) .

 

[Alan Gomes]

I need to talk to mechanic and get more details. I don’t have any exhaust smoke . There is no Hobbs . Previous owner maintained the boat well but I have no records from him other than a new exchange system was put in a few years ago . There were cooling issues but that seems to be rectified . The temp is stable and runs in the middle of the range on gauge . Given the reliable wind conditions and the fact that the boat was used exclusively in the bay ( it may have never gone offshore) , most likely the engine hours are low for its age. ( 38 years ) .

If it starts quickly, doesn't smoke, and doesn't consume oil, I don't know why you would want to replace it. Those are great engines. You could run a compression check on it, which is not that hard to do, and that will give you some idea of the engine's overall health. I think there's every possibility that you'll be dead before that engine is.

"Low hours" is not necessarily a selling point. You can put thousands of hours on these engines if you maintain them and run them properly. It's much more important how the engine was run in the past--and that's not something you'll likely be able to know. Though it might sound counterintuitive, diesel engines hate being babied. Run it at about 80% of its max rpm, under load, and it will be happy. Let it idle for hours at a time--not so much.

My advice: Just run it and don't worry about it. Keep up with the maintenance. Don't baby it. And don't worry, be happy.

 

[K2MSmith]

If it starts quickly, doesn't smoke, and doesn't consume oil, I don't know why you would want to replace it. Those are great engines. You could run a compression check on it, which is not that hard to do, and that will give you some idea of the engine's overall health. I think there's every possibility that you'll be dead before that engine is.

"Low hours" is not necessarily a selling point. You can put thousands of hours on these engines if you maintain them and run them properly. It's much more important how the engine was run in the past--and that's not something you'll likely be able to know. Though it might sound counterintuitive, diesel engines hate being babied. Run it at about 80% of its max rpm, under load, and it will be happy. Let it idle for hours at a time--not so much.

My advice: Just run it and don't worry about it. Keep up with the maintenance. Don't baby it. And don't worry, be happy.

I did a major service on it back in August and so far it has not needed any oil. it starts easily even if it’s been sitting a week or two. If it’s been started on the same day, it starts again instantly at the end of the sail. The factory paint is flaking. I’m wondering if I should plan to have it painted to avoid corrosion ? That came up in the survey when I bought the boat. I like the ”don’t worry be happy” advice I need to do more of that.

 

[Loren Beach]

Alan provides some good perspective.
Also, the cost of the replacement can vary quite a bit, depending on how you split up the labor with a professional.
Reference our experiences in my blog entries here. For one, I can not imagine wanting more HP than the Betamarine25, that I installed in 2018.
My new engine was just about $10K, on a pallet, with the upgrade alternator and connections for the water heater, and also the upgrade instrument panel.

That's quite a bit more oomph than your old 21 hp.
As you noted, there are multiple correct answers and costs to ponder.

Blog link: https://ericsonyachts.org/ie/ubs/engine-replacement-olson-34.616/
and there are 9 other entries in that series.

Further: the new engine is a lot quieter than the old one.

Regards,
Loren

 

[clayton]

As far as a refurbish/rebuild goes, the main question is how do you like to learn? As in, if you’re not already experienced working on an engine, are you willing to teach yourself? A friend I crewed for on his 38 pulled his engine and took it home and rebuilt it in his garage. He had experience working on car engines. Our diesels are pretty bulletproof, they’re tractor engines and built to withstand decades of hard work. Why not get the mechanics maintenance manual for your diesel and read through it and decide if you could do your own refurb. You should be able to find the Kubota block number designation by the injectors. Is there a Kubota dealer in your area you could go make friends with? Don’t know anything about your situation- time available, tools, experience. Just the direction my brain would go - “can I do this?. If you chose to repower, how much of the work could you do yourself? There are some recent threads on repowering that I’m sure you’ve seen. Keep us posted, not an easy choice.

 

[Alan Gomes]

By the way: The one thing you need to do YESTERDAY when you own an M25 is make absoutely sure that you do not have the old alternator bracket that attaches to the timing cover. If you do, don't run the engine again until you replace it! Those are prone to break the timing cover, and if that happens, you won't be able to find a replacement for the cover and your engine may become useless!

Read more about this upgrade here. Fortunately, this is not an especially difficult or expensive repair.

On the other hand, perhaps your M25 has already had the bracket upgrade. Just make certain yours does, and if not, fix it immediately!

 

[Alan Gomes]

I did a major service on it back in August and so far it has not needed any oil. it starts easily even if it’s been sitting a week or two. If it’s been started on the same day, it starts again instantly at the end of the sail. The factory paint is flaking. I’m wondering if I should plan to have it painted to avoid corrosion ? That came up in the survey when I bought the boat. I like the ”don’t worry be happy” advice I need to do more of that.

A can of Rustoleum from Home Depot is much cheaper than an engine replacement or even a rebuild.

 

[Alan Gomes]

As far as a refurbish/rebuild goes, the main question is how do you like to learn? As in, if you’re not already experienced working on an engine, are you willing to teach yourself? A friend I crewed for on his 38 pulled his engine and took it home and rebuilt it in his garage. He had experience working on car engines. Our diesels are pretty bulletproof, they’re tractor engines and built to withstand decades of hard work. Why not get the mechanics maintenance manual for your diesel and read through it and decide if you could do your own refurb. You should be able to find the Kubota block number designation by the injectors. Is there a Kubota dealer in your area you could go make friends with? Don’t know anything about your situation- time available, tools, experience. Just the direction my brain would go - “can I do this?. If you chose to repower, how much of the work could you do yourself? There are some recent threads on repowering that I’m sure you’ve seen. Keep us posted, not an easy choice.

To take a bit of a contrary view here: Unless there is something that hasn't been shared, why rebuild an engine that starts right up, doesn't smoke, and doesn't consume oil? Painting some places where the paint might be flaking off--sure! He could always check the compression for peace of mind I guess. And maybe it should have a valve adjustment done, just because. (He probably doesn't know when it was done last so that bit of occasional maintenance may be overdue.) But before pulling it to rebuild it, I'd at least wait until it starts consuming oil and smoking, which would suggest that it might need rings.

 

[K2MSmith]

By the way: The one thing you need to do YESTERDAY when you own an M25 is make absoutely sure that you do not have the old alternator bracket that attaches to the timing cover. If you do, don't run the engine again until you replace it! Those are prone to break the timing cover, and if that happens, you won't be able to find a replacement for the cover and your engine may become useless!

Read more about this upgrade here. Fortunately, this is not an especially difficult or expensive repair.

On the other hand, perhaps your M25 has already had the bracket upgrade. Just make certain yours does, and if not, fix it immediately!

In looking at photos in the link you sent me, the bracket looks similar on top but different on the side....I just realized I had this photo. Should have put it in my original post.

 

[Christian Williams]

Your engine is not on life support. Your diesel mechanic is on life support, trying to make a living.

Most of us have found that diesels are well within our capacity to maintain ourselves, and that passing that off to an actual mechanic is expensive and repetitive. When you need a mechanic you need him, but 95 percent of the time the issue is resolved by study, time and the reassurance of the people here--since all of us have been there.

 

[Alan Gomes]

In looking at photos in the link you sent me, the bracket looks similar on top but different on the side....I just realized I had this photo. Should have put it in my original post.

Based on the photo, it looks to me as if you have the original bracket. If so, you should replace it STAT. The consequences for breaking that cover likely would be catastrophic.

MaineSail's info is always great. I believe the Catalina 34 forum has a bunch of info on that replacement also.

 

[clayton]

I concur that if nothing indicates a rebuild is necessary why do so. My questions were based on the info being presented to K2M by a mechanic, and if he decided to rebuild how comfortable would he be doing it himself. Certainly not suggesting he pull it, take it home and rebuild it just because... My friend did his because the gasket for the oil pan was leaking and trashing his bilge. He chose to do the extras of a rebuild over a winter when he had that chance. Kubota diesels have quite a history of reliability and long service life.

 

[Rocinante33]

My original 1982 M25 engine still runs reliably but it obviously is not a new engine. The paint is peeling off and the diesel mechanic recommends a general refurbishment at some point. I just had alternator rebuilt to fix a tach problem - that was over 800 (but also included adjusting stuffing box).

When I bought the boat I was a bit naive as far as engine replacement costs (especially in this area). I knew the diesel might have to be placed eventually. no big deal how much could a 25 hp diesel engine possibly cost to replace - 5k-10k ?. . Well, I was off by orders of magnitude. A new Yanmar 30 repower with new transmission, panel and controls is going to run about 20-25K depending on prop, shaft etc.). that's almost what I paid for the boat. Not prepared to do that right now.

So my options are :

1) maintain the engine that I have and keep it on life support and make a decision in a year or two (or 3) - maybe even electric or hybrid an option at that point

2) spend money to refurbish (or rebuild ) the engine I have. I can't wait to hear how much that will cost.

3) just get a new engine eventually

Honestly, I don't want to do 3) yet as I've only had the boat less than a year and it still runs fine - budget considerations also put that out of contention if it really costs 20-25K.

Would appreciate any thoughts from owners who have gone through this scenario....

Kevin,

Definitely #1. These little engines are amazingly dependable and long lasting! It ain't broke, so don't fix it.

As far as the chipping, peeling paint, that is business as usual for any older boat. You can take care of that without much problem like this:

Go to an autoparts store or Home Depot near you and buy a spray can of engine enamel which is the correct color to match your engine (Universal Bronze, perhaps). Also get a brass detail brush like one of these..... cheapo is fine but don't use a regular metal, steel or iron wire brush.

Brass Detail Brush

Amazing deals on this Brass Detail Brush at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

3 Piece Soft Grip Wide Brush Set

Amazing deals on this 3 Piece Soft Grip Wide Detail Brush Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Take this stuff and some old newspaper and masking tape to your boat. Spread newspaper under the engine, up the sides of the engine compartment (mask/tape some up to hold it in place) and protect from general paint flakes, dust, corrosion bits, etc, Go to work on the engine with your brass wire brush. Knock off the loose, flakey paint chips and expose the metal or old paint underneath. Wipe off as much as you can with paper towels. Then paint it with your spray can. A little bit of overspray on the hoses or other engine compartment contents is no big deal. If you missed a couple of spots, spray some paint into your paint cap (do this up on the dock) and while its still wet use a small brush to dab some of the wet paint onto those spots. Clean up the paper (without spilling the crud out of it, and admire your work! It will look 100% better and will be protected from corrosion again. Repeat once per year.

Go sailing and enjoy!

Make sure you change your zincs regularly to minimize corrosion.

 

[clayton]

Mine has the bronze Universal paint peeling in places, showing the original Kubota blue. Runs like a champ, no idea as to how many hours are on it. most significant service I’ve done was to replace the fresh water/coolant circulator pump. Bought a Kubota pump for half the price. This site is a wealth of knowledge and experience with these diesels.

 

[Frank Langer]

Kevin,

Definitely #1. These little engines are amazingly dependable and long lasting! It ain't broke, so don't fix it.

As far as the chipping, peeling paint, that is business as usual for any older boat. You can take care of that without much problem like this:

Go to an autoparts store or Home Depot near you and buy a spray can of engine enamel which is the correct color to match your engine (Universal Bronze, perhaps). Also get a brass detail brush like one of these..... cheapo is fine but don't use a regular metal, steel or iron wire brush.

Brass Detail Brush

Amazing deals on this Brass Detail Brush at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

3 Piece Soft Grip Wide Brush Set

Amazing deals on this 3 Piece Soft Grip Wide Detail Brush Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Take this stuff and some old newspaper and masking tape to your boat. Spread newspaper under the engine, up the sides of the engine compartment (mask/tape some up to hold it in place) and protect from general paint flakes, dust, corrosion bits, etc, Go to work on the engine with your brass wire brush. Knock off the loose, flakey paint chips and expose the metal or old paint underneath. Wipe off as much as you can with paper towels. Then paint it with your spray can. A little bit of overspray on the hoses or other engine compartment contents is no big deal. If you missed a couple of spots, spray some paint into your paint cap (do this up on the dock) and while its still wet use a small brush to dab some of the wet paint onto those spots. Clean up the paper (without spilling the crud out of it, and admire your work! It will look 100% better and will be protected from corrosion again. Repeat once per year.

Go sailing and enjoy!

Make sure you change your zincs regularly to minimize corrosion.

Keith,
Most of our older diesels will also have some oil, coolant or other contamination on them. Painting, without thorough cleaning to remove that, will likely fail. Do you have any suggestions for how to clean before painting, without damaging any sensitive engine parts?
Frank

 

[K2MSmith]

Based on the photo, it looks to me as if you have the original bracket. If so, you should replace it STAT. The consequences for breaking that cover likely would be catastrophic.

MaineSail's info is always great. I believe the Catalina 34 forum has a bunch of info on that replacement also.

I’ll investigate further . It looks like the top part of the bracket has been replaced. I would hope with steel . It’s definitely not the replacement new bracket design though shown in that site . Is the top part the source of the failure?

 

[bigd14]

It sounds like the engine is in pretty good shape. I had similar worries when I purchased my boat because I knew nothing about diesels. Once I started looking through the manuals and learning how everything operated I got more comfortable that the engine was solid. I replaced all the hoses and wiring, did the alternator bracket mod, completely replaced the fuel system, installed some new motor mounts and I now have great confidence in the engine. In fact it started right up with no issues this past Sunday after sitting since October.

It's rarely the engine itself that causes problems, its all the systems associated with it. There are millions of Kubota tractors with thousands of hours on them that are worked much harder than our marinized diesels and they are still running. Fix up the cooling, electrical and fuel systems and you will have an engine that will run reliably for years. If it really needs extra deep cleaning and paint removal, you could move the engine into the cabin so you can access everything really well. I found it very easy to move my engine into the cabin onto a custom frame using an old mainsheet setup on a 4x4 across the companionway. https://ericsonyachts.org/ie/ubs/1984-e30-strut-replacement-part-3.497/ This also allows you to clean out the engine compartment and replace stuff back there that hasn't seen the light of day for nearly 40 years. Big job, but way better than $$ for a new engine.

Good luck!

Doug

 

[Alan Gomes]

I’ll investigate further . It looks like the top part of the bracket has been replaced. I would hope with steel . It’s definitely not the replacement new bracket design though shown in that site . Is the top part the source of the failure?

It's been quite a few years since I owned an M25. (Mine was an XP.) But based on that picture and on my (fading) memory, I don't think you want the bracket to be attached at all to that timing cover. It looks to me as if yours is. Should that timing cover crack, you are in deep doo doo. But I repeat myself!

Find out what you have to do to get the bracket shown on MaineSail's site.