Repower or repair?
- Thread starter jibes138
- Start date
Here's another M25 that had a similar fracture to the port aft bell housing flange. This one was right through the hole for the motor mount. Note the comments from a professional welder recommending NOT to weld repair it. http://www.ericsonyachts.org/infoexchange/showthread.php?14630-Broken-Motor-Mount
Our M25 continues to serve us well - no idea how many hours on it, but I bet it's not low. I have never upgraded the heat exchanger, but I'm guessing our cold Lake Michigan waters are probably the reason we get by. I have actually considered a higher temp thermostat because it seems to run too cool - rarely above 165 according to the cockpit gauge. I have replaced the glow plugs, had the alternator rebuilt, (it has the upgraded alternator bracket) and I've replaced the Oberdorfer water pump and engine mounts - that's about it! Oh yeah - front oil seal also. I did re-wire the whole thing, eliminating the trailer plug.
@eherlihy, I am curious about your comment regarding the water heater hose routing - could you elaborate on that, maybe with photos?
@eherlihy, I am curious about your comment regarding the water heater hose routing - could you elaborate on that, maybe with photos?
have you looked into a Yanmar, they may cost more but its your decision at the end of the day. Knowing what other Catalina 310 owners that have problems, my yanmar idles at 800 rpm with no vibrations and is easy to start even in cold weather.
There are only two thermostats for these engines. 160 and 180. Your boat, your choice.
Actually doesn't really matter in the big scheme of things, I've run both on our M25 in the past 18 years, now have 3266 engine hours, bought her in 1998 with 888 hours.Not so hard, and I'm not eh! The takeoff to the water heater should come off from under the thermostat, not from the line to the HX.
Here's a picture:
http://c34.org/bbs/index.php/topic,4518.msg26462.html#msg26462
It's the 3/8" hose connections from the internal water pump to the thermostat housing. I've met a number of cruisers that have eliminated the hot water heater for one reason or another. In fact, all new engines come with that "jumper" hose and you have to remove it to connect it to a water heater.
Stu's reference from Maine Sail is spot on. You can see the 3/8" ID hoses on my O'day 35 in this photo;
Plumbing the hot water heater in this way gives you hot water faster (because it is always open). When the thermostat opens, the coolant is more effective because the engine coolant is not forced through a bath of pre-heated water (in the hot water heater) in between the heat exchanger and the exhaust manifold.
After a few days of internal debate I'm leaning towards replacing the bell housing to avoid the effort of mounting a new engine and having to modify the engine mounting arrangement in the boat. Plus to get on the water sooner with maybe a repower over next winter or so. Talking to the folks at Westerbeke I found that the bell housing has been superceded and the new model has an adapter plate that allows the transmission to be removed without removing the bell housing. The current design bolts the transmission from the inside of the bell housing. The new design bolts the tranny to the adapter plate then the adapter plate to the bell housing from the outside. Sounds like a big improvement in event of future R&R activity..
My M25 is working surprisingly fine. I'm sure the PO made various upgrades such as motor mounts, 120 volt Alternator, replace fuel injectors but if I had a good reason to replace or rebuild, I would replace. The Beta gives some added horse power with the same footprint (I think) but the Yanmar gives a little more horsepower. Not sure that a couple more HP is worth the change in footprint.
I've never had a problem with horsepower. If the motor gives you hull speed at about 70 or 80% throttle that's as fast as you are going anyway. More might be better punching through waves. The Beta options are 20 or 25 HP. I can't see going lower, and the Universal M25 XPB is higher horsepower also.
I believe that you mean 120 AMP alternator... or perhaps you don't have, or need, an inverter...
My perception of Yanmar vs the Beta is that they are both very reliable if taken care of. I have had my hands on a bunch of Yanmars, but not a Beta. The Beta, however, is a Kubota block, and I've worked on a bunch of these. The Yanmar has some more elegant engineering in some areas (like the heat exchanger), and kludge in others (like the raw water pump). You will also pay a "marine" premium for Yanmar parts. The Beta, while it is based on a tractor motor, appears to have been designed to be easier to service, and parts will not carry the "marine" premium, if you know where to shop.
I also agree that the M25 has plenty of horsepower (21) for our 11,500lb boats. More horsepower would likely increase fuel consumption, but not yield much increase in speed. My M25 burns about 1/3 gallon per hour at 5.5kt cruising speed.
Yes, I meant Amps. Thanks for the correction. Our M25's are 21 horse power and the new Betas are 28 I think. The equivalent Yanmar is 30. There are times, especially when I hit the C and D canal wrong that I wish I had a little more horse power. I'm probably doing hull speed with a foul current but over the ground, I've had elderly people with walkers on shore go faster. Not sure if an extra 7 hp would help. Although these motors seem to be very reliable and last a long time, I think they probably have their limits in time and hours. I really don't know how many hours are on mine. The meter stopped at 4,000.
Beta makes a 20, a 25, they made a 28 but I don't see it listed on their site, and they make a 30 - all of these are 3 cylinder, and I believe that any of which would be applicable for our O'day 34/35.
If I had the funds, I would probably opt for a Beta 25 with my own alternator upgrade (40A is too little, and so is 75A), I would have Beta install the hot water fittings on the thermostat bypass and I would opt for the CW control panel (with a recess).
If I had the funds, I would probably opt for a Beta 25 with my own alternator upgrade (40A is too little, and so is 75A), I would have Beta install the hot water fittings on the thermostat bypass and I would opt for the CW control panel (with a recess).
Well it looks like I'm going with a new motor. I fired up the Universal last night and it started right up. I put a 5/8 bolt with fender washers in the broken flange to hold it together and it seemed to work at idle or just above. Should get me to the marina. In checking for leaks I noted a large amount of oil in the pan under the engine, so it looks like it has a bad seal on the shaft. I might be parting out the motor when I get done, it has the alternator bracket upgrade kit and 3 inch heat exchanger, both within the last year or two. Still fires up immediately. I debated going with the beta 20 but cost isn't much difference. Our old Universals with wear are likely less than 21 horses and who runs WOT anyway? The 25 should allow cruising over 6 knots. An extra knot an hour is big on an all day run under power like on the ICW.
The extra horses will also enable a higher amperage alternator without affecting your cruising speed. I forget the formula but recall that I once calculated that my 90 amp alternator requires about 1.5 hp to produce 90 amps (which is rarely if ever).
Here's when, why and how I deal with it. Maine Sail prefers belt (or amp) manager on regulators.
Alternator heat, Regulator Controls, Small Engine Mode
http://c34.org/bbs/index.php/topic,4454.0.html
Small Engine Mode - discussion with link to the picture of the toggle switch: http://c34.org/bbs/index.php/topic,4454.msg27149.html#msg27149
Small Engine Mode - the picture of the toggle switch http://c34.org/bbs/index.php/topic,4669.0.html
I understand. And used this on the way up the coast last summer. I normally would cruise at 2450 but bumped it up to 2800 (3000 is WOT). I gained a half a knot.
Good luck, Dave. Good choice.
A knot is a speed of one nautical mile/hour. Thus, an "extra knot an hour" would be an extra nautical mile/hour/hour--i.e., an acceleration. At the end of an all-day run you'd be travelling at 15 to 20 knots!
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Too bad about the need for a new motor. In replacing it, however, you'll be confident in the engine for the next 30 years. You could probably sell the old engine on eBay (I may have already suggested this earlier in the thread).
In order to "limp back to the marina" I would use (or have as a backup) a pair of Vise-Grips to hold that motor mount together. While replacing the motor, you will probably have to remove and shorten the prop shaft. This means that you will also have to drop the rudder. (If it were me, I would simply get a new prop shaft. - in for a penny...) I would advise replacing the cutlass bearing while you're there. I started a thread about my adventure with this here; http://www.sailnet.com/forums/gear-maintenance/80089-contemplating-drive-line-overhaul.html
While I was at it, I also installed a PSS Shaft Seal, and am quite happy with it.
Here are the parts that I refurbished (propellor), replaced (prop shaft, cutlass bearing and coupling), or added (PSS seal):
Before:
After:
Stu - on my Leece-Nevill 90 Amp alternator, I have been using the 8MR (dumb) regulator, and it serves my needs with a 220AH house bank nicely. My energy needs are modest (all LED lighting. No windlass, inverter or refrigeration. SOC monitored by a SmartGauge. I have never dropped below 50% SOC.). Of course, I'm not using it to it's fullest potential, but the Leece-Nevill is FAR better and more reliable than the stock Motorla 55A alternator.
In order to "limp back to the marina" I would use (or have as a backup) a pair of Vise-Grips to hold that motor mount together. While replacing the motor, you will probably have to remove and shorten the prop shaft. This means that you will also have to drop the rudder. (If it were me, I would simply get a new prop shaft. - in for a penny...) I would advise replacing the cutlass bearing while you're there. I started a thread about my adventure with this here; http://www.sailnet.com/forums/gear-maintenance/80089-contemplating-drive-line-overhaul.html
While I was at it, I also installed a PSS Shaft Seal, and am quite happy with it.
Here are the parts that I refurbished (propellor), replaced (prop shaft, cutlass bearing and coupling), or added (PSS seal):
Before:
After:
Stu - on my Leece-Nevill 90 Amp alternator, I have been using the 8MR (dumb) regulator, and it serves my needs with a 220AH house bank nicely. My energy needs are modest (all LED lighting. No windlass, inverter or refrigeration. SOC monitored by a SmartGauge. I have never dropped below 50% SOC.). Of course, I'm not using it to it's fullest potential, but the Leece-Nevill is FAR better and more reliable than the stock Motorla 55A alternator.
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