411 engine replacements
I have a 411 with a Perkins 4.108 Marine Diesel engine which leaks a lot of oil (more than usual, has been looked at, doesn't have much power, will do in most cases for getting in and out of the harbor and charging batteries but not much more). I'm interested in any and all info about what replacement engines you have gotten, how they have worked out and why? Hope to hear from you soon, Pippo

Pippo

There are several possible engines in the 40 hp range if you consider that suitable, suggest you look at well known brands. They are smaller for the same hp now, and should fit in without problems. The recommendation is to choose a low rpm engine, and select the reduction ratio to fit a fairly big propeller diameter. Originally it was 21" and produced well over 7 knots top speed

Lars

Pippo

Lars, many thanks for your recommendation : 40 hp range, low rpm engine, and reduction ratio to fit a fairly big propeller diameter.
As you know there were 42 4.11s made, and 61 41s constructed, they all had the same Perkins engine. Together there are about 50 registered on the S&S site. I wonder how many have replaced engines. What they have put in and if they are happy with change. Is there some way of contacting the registered owners? Thinks again for your help, Pippo

Hello Pippo.

We have Swan 41 nb 22. So it might interest you to know that we have replaced our original Perkins 4108, by a rebuilt one, and are perfectly happy with it. I had the same questions as yourself, and after some discussions,  including with the professor, and also reading Practical Boat Owner (rather useful British magazine) I felt there was too much complications and costs involved to install a different engine. So, maybe it is noisy, and not fully "up to date" but we kept the same exhaust, water inlet and heat exchanger, gearbox, electric system, etc... And the weight distribution is unchanged.

Rebuilt Perkins 4108 can still be found I believe: I have one address in Cannes

SDM  (PERKINS)

158 av. Michel Jourdan

06150 CANNES LA BOCCA

Tel : 04 93 90 62 94

Internet : www.lasalledesmoteurs.fr

Mail : lasalledesmoteurs@wanadoo.fr

This was done in 1999.

I also never found a really nice way to install a proper wet exhaust due to the lack of space in the rear cabin where the water-lock and rubber exhaust should normally go. So I kept the original dry exhaust (adding some anodes, despite the fact that it never leaked - touch wood!) and replaced the original high temperature rubber by stainles steel flexible hose (50mm diameter) originally designed for trucks. For the time being everything is fine. I can give you informations on a supplier (french again!).

I hope this helps.

Kind regards and happy sailing!

Hello Pippo,
I know that substituting the old Perkins 4.108 with a new engine is possible and not too difficult. Not only, but the cost of doing this is comparable to a good overhaul of the old engine (in any case not larger than the double). Some of the people attending this forum did it and I hope that they will tell us about.
As far as I am concerned, I still have the 4.108 and would like to keep it for the entire life of the boat (or my own...) going through necessary periodical overhauls.
I know that there are pros and cons in both possibilities but, considering the overall sum, I tend to believe that the choice is a matter of mostly personal taste and not a real necessity given by a relevant difference in issues like, for example, costs, reliability and durability.
I would be very interested in a wider discussion and in analyzing such issues with more precise data.
Daniel, 411-004

Hello,

May I intervene in the discussion bringing about the general argument of keeping an old engine versus replacing it with a a new one.

I have tried both options.  I had a Volvo MD 21 sitting in my boat since she was build in 1980. In 2000, I did a minor overhaul replacing the exhaust system, the water pump and many other things. It worked satisfactorily for a season or two. Later, it started to smoke a little more than normal, and I must confess, it was a little embarrassing, especially in marinas! So, I decided for another overhaul, this time a major one. The top was dismantled and completely renewed for a substantial cost. During this process, I became aware of how crazy some of the parts are placed as if they are supposed to be hidden. Furthermore, despite this second overhaul, the engine continued to smoke happily and quite more than normal.

Some would probably say leave it to smoke as long as it works. Indeed, it worked fine and I could leave it be. However, I was very disturbed by the smoke and by the inaccessibility of things that needed attention. I became also more and more worried that my spending on an old rusty beast was not wise.

So, finally, I decided to replace it. It was an excellent decision and my only regret is that of not deciding for a replacement before the second overhaul. It would have saved me half of the replacement cost.

I do not know with precision about the distribution of the weight, but all the rest has worked perfectly well after some adjustments:

1-the electrical part was no problem at all since the new engine,  a Volvo D2-75 has this modern EVC system, a sort of plug and play electrical device which even includes NMEA.

2-The old exhaust (earlier overhauled) could be used with some adjustments.

3- There was no issue with the space since the new engine is a little smaller and a shorter than the old one. A little adjustment of the bedding was necessary though.

4- The new engine being shorter, I had to replace the shaft with a longer one.

All in all, the decision to go for a new engine was right and should have been taken before the second costly overhaul.

Cheers

/Philippe/ Swan47

I fully agree with the fact that "in situ" repair is not worth the cost. We also tried it, as the 4108 original engine had been quite overheated when delivered to us as we bought 41/022. It was expensive and only lasted for about two or three years.

Buying a rebuilt engine is an entirely different issue, as if properly done it is entirely rebuilt replacing all worn parts by new ones. It also gives the opportunity to test the transmission.

Buying new engine plus new transmission is certainly more expensive than a rebuilt engine.  At the end of the day: is it not a matter of budget you are ready to spend??

In any case, not a straighforward decision.