Universal M25XP in Koinonia is a success

[Koinonia]

Today I got the last of things buttoned up and slid Koinonia back into the water with her new engine.  It was a tight fit but it worked out well.  The old 12X9 2 blade prop was removed and a 13X13 3 blade put on.  At idle I was doing 3.5 knots leaving the sailing club, out on open water at around 2000 rpm I was making around 6.2 knots and with the motor reved up to around 2800 she was running at 6.9 knots.  I live inland so I didnt have surfers gathering to get on my sternwave which was huge.  I will post again later this week with pictures as well as more information.

[Koinonia]

One of the pictures with the teak step in place was corrupt so I couldnt show just how close the fit was.  To start this project I started with a find on craigs list.  A guy had a kubota motor advertised that was coming out of a golf course lawn mower, this happened to be a D950 engine and was rebuilt by Engine Power Source in Charlotte NC.  The motor was clean and showed little use as the guy had gotten the mower but the hydraulics were to far gone to save the whole mower, short story is it was mine for $500.  Originally I had noticed part numbers for the transmissions, raw water pumps, ect were the same from the M12 to M25xp motors.  So I had thought about taking my motor out and taking the needed parts off and putting them on the larger D950 block.  One part that has a differant number is the transmission bell housing.  I dont know for sure if it will fit or not and it would still leave short the heat exchanger and exhaust manifold.

I was searching around on craigfind and found a M25 motor, complete but in parts since the guy had Westerbeke look at it. They had torn the engine itself apart and deemed it not worth the rebuild.  Price was $200 and everything was there, and since the M25 is a D850 block which has an almost identical exterior I know the water pump, trans, and other parts would bolt right up.

Everything got bolted up, test run and painted, before starting this project I took ALOT of measurments to ensure a fit. I knew it would be close, while I had the engine area clear I pulled the prop and shaft off the boat and replaced the shaft log hose.  When replacing the hose I made it about 2 inches shorter knowing the flange on the engine would be further back in the boat.  While out I also hit the shaft with emory cloth to clean it up and repacked the stuffing box. 

Initial installation had the motor sitting to high with the back two mounts at their lowest position.  I solved this by pulling the motor back out and removing the adjustment nut and using two stainless washers to shim the motor.  This along with proper adjustment on the front mounts got me the proper alighnment to the shafts flange.  After the install the prop is now about 1.5 inches further away from the boat.  I was curious about this and have another shaft that I can cut short to length and machine the flange end but I decided to give the boat a shot with the prop further back.  The original prop was a 12X9 two blade.  Gerry Hutchins informed me that in 94 they were using a 14X14  2 blade with the newer Westerbeke engines.   My concern with the prop so close to the boat is wondering how its ability to get good water behind that fiberglass skeg is.  My new prop is a 13X13 2 blade, I also did some looking around and found out catalina 30 owners like to use an extendo prop to get a bigger blade on their boats, if they can do this why cant I?  I wasnt looking to get bigger on the blade but liked the idea of getting more distance between the blade and the boat.  This also would appear to get it better water being further back. 

The rest of the motor install was pretty strait forward, I had to relocate my grounding buss bar and as you can see I had to cut a hole to give the alternator clearance.  As seen in my earlier post the results are pretty good and am getting my speed that I want at about 2/3rds throttle so if we need that boost of power we have it.  We will be heading to south Florida again this June for a month and will be cruising the keys mainly.  We will launch out of Laishley marina again in Punta Gorda and making the crossing down.  If there isnt alot of wind the new iron genny will take care of things.  Also if anybody noticed the heat exchanger isnt stock.  Its from a Perkins 4108 that I got a good deal on and I feel assured I wont have any overheating issued if I were to need to run at maximum operating RPM for an extended time as the original exchangers are prone to overheating when run hard.

I thought about using a large 2 cylinder Yanmar but there is the initial cost and then spare parts get pricey.  The great thing about universal engine is their reliability and spare parts are easy to come by at a great price.  Alot of people recomend the kubota tractor dealers for parts, the industrial rout is much cheaper and I use engine power source out of Rock HIll SC.  All you need is the engine code, I usually check my pdf files so I already have the part number ready.  There are a few differant shops around the country and a google search will help you get the closest one.  When traveling I will have a good selection of spare parts on board.



100_2365 by koinonia27, on Flickr



100_2366 by koinonia27, on Flickr



100_2367 by koinonia27, on Flickr


100_2368 by koinonia27, on Flickr



100_2369 by koinonia27, on Flickr

[MacGyver]

Good job!
Looks great!

Did you have any trouble lining up the shaft?

Mac

[Koinonia]

Took a long while and would be so much easier with two people.  I was going from the cabin, to the lazarette and back again so many times to get it just right.  The odd thing is having to cut the holes in the front of the two engine beds to stick a hand up the hollow space to put a wrench on the nuts to keep them from turning, never have seen this before.  There are backing plates on the bottom side of the fiberglass engine beds.

[Allure2sail]

Nice job...
Have played with idea of doing an engine upgrade but think I will most likely move up to a bigger boat. You definitely made a few great buys to get you there, and the bigger heat exchanger was a good idea as well. The only engine I've run across was an M18 (which was 15 hp) and the consignment shop wanted $1,200 for it. Couldn't justify 4 or 5 horsepower for that price. You absolutely correct in your getting your parts from Kubota dealer I learned that a few years back, what a savings  (as long as you can identify the engine model number from Kubota). Good job...enjoy the peace of mind knowing you can push through what gets thrown at you.

[Koinonia]

I just remembered something, I had to use my original alternator on the new engine setup.  This effects the RPM guage since thats where it gets its reading from.  Now the variable comes into play, the M12 has a 4in diameter crank pulley.  The M25xp has a 4.5in diameter crank pulley and no they arent interchangable.  If I remember right the M12 has a spline that the pulley is on and the M25XP is a keyway.  so I did some math and at my rpm guage reading 2500rpm I should actually be turning 2200 roughly, its 2222 if you want to be technical.  At 3000rpm on the guage im turning 2666rpm which is just barely above peak operating range.  I wont be doing this very often though since when I opened it up the boat will get up to 6.9 knots pretty quick and thats it, though from what Ive read that is the theoretical hull speed.  Im very happy to be on the lower end of operating range and makeing 6.4 knots on GPS.

[Koinonia]

Finally got some strong winds and some chop on our inland lake today.  My wife and I took the boat accross the lake to a nice place on the water for dinner, winds were gusting to 35 and waves were around 1.5ft with the occasional 2ft and bigger.  On our lake this is rough as it gets.  At 2200 the boat was able to maintain 5.8 knots going strait into the wind and waves.  Throttled up to 2800 and could still make a steady 6.2 to 6.3 knots.  The boat had no trouble splitting through the waves, if it wasnt for our dodger we would have been soaked.  I dont recall at the moment if I mentioned it but to be correct on the prop Im a little overpitched.  I cant get up to redline though I can operate though my operating range fine.  I like that I can make good speed at the bottom of my operating range.  To try and run the engine any higher in rpm would be pointless since the boat already makes hull speed.  Docking even in the wind is also easier with the propwalk  being almost non existant.  If anybody has any thoughts on going with this engine setup feel free to PM anytime.

[Allure2sail]

Hi;
I noticed your alternator bracket had the adjustment slot on the engine end, is that the M-12 bracket flipped around or is it the M-25 bracket. I know you ended up using the M-12 alternator, is there an output difference between the two? One of the things that I am not able to get right on Allure is the alternator belt fit. A new belt adjusted properly has the alternator at the end of the adjustment slot on the bracket. It's fine at the beginning of the season but by the end of the season it is looser than I like and I put a new one on every spring. I have never thrown off or destroyed a belt. The next smaller length belt available is a little to short to get on the engine (believe me I've tried) and nobody list a belt in between the them two sizes. I'm considering elongating the slot in the bracket on the engine end to get the smaller belt on initially, at least I would have some adjustment on it as they always stretch a little once you run them awhile. Has any one else had this problem with a belt on a M-12?
Thanks
Bruce
S/V Allure

[Koinonia]

I just flipped that top adjusting bracket around, I liked the fit better on my particular install.  I'm not really worried about the amp output of my alternator since its a diesel and the only power required for running is for the electric fuel pump supplying the high pressure pump. As far as charging goes my solar setup takes care of me.
   Where are you getting your belts from?  Napa has a better size selection than anybody else by far.

[Allure2sail]

Hi;
I've tried NAPA and all of the local autopart chains and the next smaller (shorter) belt it is almost good but I can't get it over the pulley. I'm going to remove the bolt that goes through the slotted bracket and see if I can get the alternator to pivot over just a little bit more. I think if I can get the belt on and sitting in the groove on the two pulleys I might be able to get the bolt back in and tightend up. Once I run the motor for a short time I think it will be fine. They usually stretch a small amount at the beginning and that's all I really need. Honestly if the belt new was a 1/4" to 3/8" inch longer it would be perfect. I'm going to get the spec's on the belt (I've got a few of them) and list the Length, width, and part number here. Like I was saying in the previous post they get installed with the alternator at the end of the adjustment slot so as the get stretched I can not adjust them anymore so I just put a new one on every spring.
Thanks
Bruce

[skip1930]

A squeaky tight drive belt is going to work a bearing to death.

skip.

[Allure2sail]

Hi skip1930:
After an hour or so of running it will have stretched out enough to not be a problem. All drive belts have a"set" time of a few hours which ends up adding 1% to 2% to their manufactured listed overall length. That is why all drive belts whether it be automotive, industrial, marine or any other applications have an adjustment on what they drive in the form of a slotted mounting bracket or a spring loaded idler pulley to take up the slack due to not only wear but the stretching as well.
Thank you for your input.....always appreciated.
Bruce
S/V Allure