The Hallberg-Rassy 31 Monsun Forum

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Have you changed your Monsun engine? - Engine and drive train - Monsun Forum

Have you changed your Monsun engine?

Author Message

Date sent: 2016/11/06 17:42:22
The original engines in Monsuns were Volvo Penta MD2B until 1976, and thereafter it was the Volvo Penta MD11C. These engines are now so old that many Monsun owners have gone about replacing them. It is interesting for us other Monsun owners to hear what kinda engine you have installed, and how pleased you are with the change...

Date sent: 2016/11/08 21:45:55
in 2005 we've installed a NANNI 29 HP.
until now we are very pleased with it.

grt. Compaen.

Date sent: 2016/11/08 22:09:05
Installed a Yanmar 3 F (27 hp) in 2000. Have been more than happy with this engine. Nothing done so so far except normal season service done by myself.

Date sent: 2016/11/08 22:13:21
Hi, yes I've changed to an Nanni 4.150 38hp and 4cyl. Approx. 12 years ago and still doing an fantastic job without any repairs so far :-) # 186 Sirona III

Date sent: 2016/11/08 22:27:18
We have a Beta Marine 30 hp, based on the same Kubota engine as Nanni. Just painted with red paint. Link: Our engine is the shallow sump version. With 30 hp and big propeller the engine gives more than enough power to Monsun in any wind. It fits well in the Monsun engine room and there was no need to make major changes in the engine supports. Just some aluminium shims under the engine supports.

Notice that the engine's original fuel pump may not be powerful enough to secure flow of diesel from Monsun's tank, which is deep in the bilge. You can add a standard electric fuel pump provided by Beta Marine or do as we did, instal an additional day tank in the port side locker. Our daytank in 40 litres and it also helps to maintain the fuel clean for the engine.

Date sent: 2016/11/08 23:54:01
Hi Albertina515
Would it be possible to show some pictures on how you did that?
I would be interested in the extra diesel tank.
Kind regards,

Date sent: 2016/11/09 08:29:58

we installed a Sole Mini29 (27 HP) in 2015 and a new feathering Prop (G-Prop). Works all very well.


Date sent: 2016/11/09 11:15:27
I can get some pictures when I will be at the boat next time. And of course the day tank is in the port side locker...
Mikko / Sy Albertina #515

Date sent: 2016/11/09 14:25:29
....I´m right at it these days regarding a new engine.. We did chose a Volvo D1-30 and are half way there. We had a few sailingbuddys in our homeharbour with this engine and they are very pleased with this little engine.


Date sent: 2016/11/09 22:36:55
I changed the original MD 11C. in 1998, with a Volvo Penta 2020 B in Västeras Sweden before start of an ocean cruise. When I arrived in Santa Cruz Teneriffe, Canary Islands, the engine lost power and smoked. Diagnosis; Faulty installation. Repaired the engine and Continued with the cruise. A year later when I arrived at San Francisco Bay, the same problem. Exchanged with a new Volvo penta, MD2020 D with modification in the exhaust system and addition of raisers. No problem since; however I wish I had gone for a larger and more powerful engine.

Date sent: 2016/11/09 22:38:27
removed - not answer to topic question

Date sent: 2016/11/14 12:59:37
removed - not answer to topic question

Date sent: 2016/11/16 11:06:22
Hello Jostrob, I was thinking of getting a Solé to replace my MD 11. Was there any difficulties and big jobs to do in the motorroom? What about shaft and propeller? I would be very pleased to get some answers:)
Kind Anna

Date sent: 2016/11/17 13:42:45
Hello Anna,
Nothing special. It was done by a shipyard in Lemmer (NL). The motor mounts have not been changed. Of course a new diesel return line to the tank needed to be installed, since the MD11 did not need that. Shaft and Propeller have both been replaced. The shaft was to short for the new motor and the propeller needs to be replaced because the direction of rotation of the Sole 29 Mini is right whereas the MD11 turns left. I took the opportunity to replace the old prop with a feathering propeller wich greatly enhances light wind performance.


Date sent: 2017/02/24 12:33:10
Replaced a rebuildt VP 2002 91 with a boxfresh VP D1 30 last season.
Also bought the brackett set from VP which supposedly should fit with the original 2002 holes. It kind of did:)
Did the operation myself with a somewhat more competent friend assisting. Did it in a marina where there was a crane for me to borrow for the lift.

Huge improvement. Made me more confident with the boat, and the extra power makes a huges difference. Also Im a lot more competent on operating and troubleshooting enginematters as well as general understanding of the boat. (only had her 2 seasons, prior to that never been on sailboat or laid my hands on an engine). Time spent crawling around down there brought a lot of new learnings and new competencies.
After almost sinking her in the marina, I Fitted new through hulls and changed the somewhat risky original cockpit dreneage solution while messing around in the engineroom.

Date sent: 2017/02/24 14:43:06
Hi Morten
Could you please upload som photos of your new engine..... I´m almost ready for installing our new D1-30 (next week) and would like to see how it look´s in your Monsun.


Date sent: 2017/02/26 20:59:03
Installed a Mitsubishi K3D 23hp a year ago, it runs like an orchestra with the 3 blade propellor

Date sent: 2017/03/17 13:24:00
Hi all,
after reading your posts I thought that maybe I´m a little underpowered.
In reality I did´t fell like this on the water with my Yanmar 21hp and 2bladed propeller.
Kind regards

Date sent: 2017/03/28 02:25:44
I also have a D1-30 installed. It is a great engine. I did have a problem with the anti-siphon valve. Which allowed water to come back into the engine a couple times. I have since moved the siphon break up, into the cockpit locker so it sits a little higher. But otherwise, the engine runs terrific.

Date sent: 2017/03/28 05:11:19
Hi Colmena.
Can you tell me what size tour propeller is for the D1-30 engine??

Date sent: 2017/03/29 11:49:29
Hi all,

This week I made the maiden start of the new VP D1-30 in our Monsun. I have made the installation on my own with help from the yard for the lift.

Peter, I installed a fixed 3-blade 16"x9" after recommendations from the supplier.

The boat is not in the water yet so I can´t say anything about the result but it definitely runs more sofisticated.

Date sent: 2017/03/29 18:07:05
Hi....I just checked the new propeller on Kris`.... it`s a 16"x12" and it is also a D1-30.... What a difference... excited to exchange my experience with you when we float again. Without knowing a lot about prop-sizes i think it sound´s like a huge difference.......


Date sent: 2018/01/12 23:20:53
Hello Jostrob again! My old md11 had to go with me one more season! But now I got a good price for the Solé. Are you still happy with yours?

Date sent: 2018/01/23 16:53:02

The Sole is a fine engine. I once installed one in our Skilsø 23 and was fully satisfied.... I still think you should check out the Craftmann.... I`m sure that i have read that the coolerunit is made from solid bronze... the basic engine is as far as i know the exact same as Sole...a Mitshubitshi.

Regards Peter

Date sent: 2018/01/25 18:36:46
Now Peter, where does the Craftsmann come from? Have you discussed that earlier in the Forum?

Date sent: 2018/01/25 18:58:35
..... I think the Craftmann is Dutch made but the basic engine is for sure a Mitsubishi.


Date sent: 2018/05/07 12:53:50
Some update regarding the installation on Linnea. We actually changed the propeller ta 16x12" after asking another supplyer. After that we are very satisfied.

Date sent: 2018/07/24 12:53:29
Hello Anna,
sorry for answering late. Haven't been here since some time.
Yes I am still happy with the Sole. It is a nice reliable engine. The only drawbacks are the accessibilities of Impeller, oil filter and oil dipstick in the monsun motor compartment. There are other Mitsubishi based engines where this is much better. If I remember right, the Craftman is one such example.

Date sent: 2018/08/17 15:33:59
It has become time to install a new engine in Isabell. The old VP MD11C has done enough. After contacting a lot of shipyards to try and get help for an engine change, I have decided to fit the Kubota engine Beta marine 30. According to the yard-technicians this engine is more easily fitted in the Monsun engine room than som of the alternatives. Costwise it does not make such a big difference what engine to choose, I find. This is going to be a major investment, that is for sure. I wil try and document the change if possible.
Thanks for all the great tips!

Date sent: 2018/08/17 17:28:23
Johannes, we have been quite happy with our Beta Kubota. Just pay attention to the fuel pump and return lines installation, they need to be in line with Beta Marines recommendations. Please contact me if you have any questions, I can try to help with pictures etc. if needed.
Mikko/ Sy Albertina #515

Date sent: 2018/08/20 13:58:08
Hello Johannes
I mounted a Nanni 3.30 which is build also on the Kobuto engine.
The gearbox is TMC40 gear, red: 2,6:1 and propeller 3bl 17x12 inch. The Monsun has very fine space for that size prop.
But there was a minor problem with fundament space - i had to cut some of the side of fundament, but no problem it is so solid build. Under almost all the fiberglas foundation there is 10mm steel plate.
With that size prop. the max rpm on engine is app. 3000 rpm.
But we never use that max rpm. when on engine (no wind) the speed is 6 kn at 1900 rpm.
Regards Thomas

Date sent: 2018/08/20 18:13:59
Thank you for the recommendations on the Kubota engine installation, it would be nice to see some pictures of the fuel pump installation and return line feed for the fuel, Mikko. I will have a shipyard in Sweden install the engine and do the alignment in the end of October 2018. But I can discuss with them the specifics of the installation.

Date sent: 2018/08/20 19:15:51
Hi Johannes.
I did the installation my self and chose a Volvo Penta D1-30.
At aprox 1500 rpm our speed is 5 nm.
I also had to make a return of diesel.
I did mount an extra double CAV fuelfilter to avoid changing the original Volvo fuelfilter…. two of these CAV filtres only cost 10 euro i Denmark.


Date sent: 2018/08/20 19:16:49


Date sent: 2018/08/20 19:20:57

At the last picture you can see the fuel return-line on top of the big cupperpipe. I had a guy attaching it on top of the big pipe along with the cupperpipe to the oilheater.


Date sent: 2018/08/21 10:30:14
When I installed the Nanni N 30.3 (kobuto) engine, As fuel returnline I used the existing copper pipe that goes to the hand pump, used to pump from the bottom of the diesel tank.
Just connected with a T-piece on the pipe in the engine compartment.
Although the engine manual writes that it may be necessary to install an electric pump, I would first give it a try without this electric pump.
The engine has now been running 55 hours since the installation in the spring.
The tank in the keel is now almost empty - about 20 liters left - and everything is still fine.
So if I were you I would try without an electric pump and a day tank.

Regards Thomas

AIOLOS # 626

Date sent: 2019/03/16 10:38:07
hey all , this is my first post in this wonderful forum. thanks for having me !

iI had a question regarding the MD2B which i have in my monsun which i bought last year. the motor has been petted and carefully serviced in all this 40 years by the previous 2 owners and it runs flawless. maybe abit smokey at start but it really works well.

so here my question:
so why wouldnt this motor last another 20 years?
and how can someone measure the risk of possible motorfailure in such an old machine ? (which would be the only dangerous point in keeping the MD2B...i guess)

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