Air cooled diesel engine

[BChandler]

What are the negatives of fitting a air cooled diesel? Surely as long as there is a decent vent for the air from the engine driven fan to escape there should not be any problems. I was thinking of the small diesels fitted to generators and such like.

Bryan C.

ps. Sail boat installation.

 

[toad]

Noise,heat and a dry exhaust(fire risk).

 

[Avocet]

You'll be doing well to get enough air to it without making the installation very noisy! There will have to be big gaps in the engine bay to allow cold air in and hot air out. These will leak noise like nothing on earth!

Other comments about hot exhaust etc. are also likely to be true.

 

[spark]

Many years ago we fitted an air cooled 3-cylinder Lister into a fishing boat (fisherman had decided cheaper is better). Despite repeated attempts at sound-proofing fisherman had to wear ear defenders all day, every day.

Don't do it.

 

[aztec]

yep agree with the others, noise. that's it quite simply glad to get shot of my last boat, 18ft fishing boat with slanzi twin diesel. too bloody noisy.

get indirect water cooled, lasts better, and quieter.

 

[wpsalm]

Re: Air cooled engine good idea

for really small sailing boats. lighter cheaper hardly any maintenance. I use a 3 hp Yanmar to run an alternater for battery charging. a water cooled exhaust is simple to put together from stock parts. with exception of the exaust manifold which a competant welder could make in less than an hr. as for using the engine to drive the boat will have some thinking to do on that one. prop size shaft couplings do you need a reverse gear ? etc.etc.

 

[dickh]

Re: Air cooled engine good idea

Don't forget that if you use a small industrial engine like the Yanmar, you MUST fit a gearbox with an integral thrust bearing to take the prop thrust.
A possible gearbox is a Snow-Nabstedt - this is a Fwd/Rev Epycyclic gearbox of about 2½:1 reduction ratio, and they make a specific one for boats - and if I remember goes up to about 10HP - can't remember where you get them from in the UK, they are made in the US - always wondered why they were never used on small boats in the UK - would be ideal in a small launch. I used them a lot in an industrial application and they were good. Try a web search if you are interested or PM me and I might still have details at home.

dickh
I'd rather be sailing... /forums/images/icons/smile.gif