VW diesel marine conversions

[moTthediesel]

Anybody here have any experience with converting these engines for marine use? I have had several in cars and have found them to be well engineered, economical, and long lasting.
Here in the States they are surely the most readily available and least expensive source for diesels in the 40 to 60 hp (normaly aspirated) class, and yet I can find almost no information about their use in boats.
moT

 

[SeaSpark]

Volkswagen Marine

VW came with the same idea:

http://www.vw-marine.de/index.php?id=33&L=1

Their marine engines are based on blocks used in cars, perhaps you can find a dealer somewhere near and spy on how they did it.

 

[dougfrolich]

If you are talking about70's,80's vintage then they were called Pathfinder Diesels

 

[antonfourie]

And there I had been thinking that car engines were not robust enough for marine use .......

 

[SeaSpark]

Marinising diesel engine:

Converting a diesel engine for marine use is mostly known as marinising.

Good source for parts and information:
http://www.lancingmarine.com

 

[sal's Dad]

I have similar questions with respect to a Datsun Diesel - seems like the trickiest part is converting to a wet exhaust. If you can stick with a dry exhaust, and a keel-cooler, it should be relatively straightforward!

Sal's Dad

 

[moTthediesel]

I really would like to stick with a conventional wet exhaust. I've thought of using a copper tubing wrap around the manifold, but the VW is not a cross flow head, so there is not a lot of room between the two manifolds. Heating the intake air by "cooking" the intake manifold is deff not good practice.
Are you talking about using the 6 cylinder Maxima engine? If memory serves, that's also not a cross flow head, so you may have the same problem?
moT

 

[sal's Dad]

A cousin has offered the motor from an '82 Datsun pickup - 4 cylinder SD22, as I recall. this and the sister SD33 (6 cyl) are used in forklifts and the like.

As it will be in an aluminum boat (no combustible material ), I was thinking to just run it hot, and maybe put some insulation around it if required.

In any event, I've scaled down the project for now, and the diesel is WAY too big for the 19' Atkin Rescue Minor. "She whose whim is law" has told me that if RM works, I can build a bigger one next year! So I have some time to figure out the diesel installation.

Sal's Dad

 

[moTthediesel]

Funny that you should mention that old Atkin design --
I take it you saw the piece about the "Rescue Minor" in the current WB? I must say that artical is food for thought, -- I was mightily impressed.
I was thinking of a larger version of that bottom under a light and simple raised deck pilothouse cruiser of around 28'. Something that could be powered by a cheap and light diesel of around 40 hp, like - say, a 4 cyl VW?
And so a thread is born --

Re: The Nissan 4 pot diesel
I have no personal experience with them, but I've heard good things about'm. If I'm not mistaken, they were used in some mid-eighties Fords (Escort, Tempo, Ranger PU) as well.
moT

 

[sal's Dad]

Yes! That's exactly my thinking - scale up either Rescue Minor, or "Shoals Runner" (WA's last tunnel design, very cool underbody) unless Mrs Atkin has another design in the mid 20' range that she's keeping secret....

http://www.boat-links.com/Atkinco/Utilities/ShoalsRunner.html

I don't have time for a full discussion now - but will be back Monday!

 

[lucas12]

There are many ways to disipate heat from a hot source, they usually involve copper as being the most conductive, cheap, and maliable material.
If it is easy to copper plate the manifold, at a plating plant, (I'd have it bead blasted first) then further down the mainfold on the straightest section as close as possible to the exhaust ports, braze on a copper jacket with the water pumping through.
On the hot end where you can't fit the jacket, insulate it with ceramic wool that's used in furnace building, it's rated to 1260Deg C, the heat build up will transfer to the heat exchange further down.
Another way would be to leave it all alone and leave on the viscous fan to take in cooling air through a grill in the engine box and duct it out of the stern.
Another idea would be to simply cool the air in the box with honey comb aluminium lining the box and aluminium or copper tubes running through the honeycomb (just like a radiator) but very thin and with plenty of room for the surrounding air to circulate around.
Trust me an engine bay in a car doesn't get alot of air cooling, constantly cooling the surrounding air to 20deg C will be plenty.

 

[Poida]

Trust me an engine bay in a car doesn't get alot of air cooling, constantly cooling the surrounding air to 20deg C will be plenty.

G'day Lucas
Should we trust a man who can't spell the name of his country properly?

An engine in an engine bay may not get a lot of cooling, but it gets enough. One area that tends to get forgotten is the cooling of the oil sump which gets a lot of air circulation. Also the radiator fan is not only there to cool the radiator but to blow air over the exhaust manifold.

The exhaust manifold on my boat is rather crude. The water return from the engine is sprayed inside the manifold and blown out of the exhaust.

One of the problems of this, evident from the top overhaul I am doing at the moment, is if your exhaust valves are not seating properly you can suck salt water into your combustion chamber.

 

[lucas12]

So I did spell Australia wrong, who cares, we have the highest tax rates in the world, and the rest of the revenue collection which as around every corner, the last thing I could ever be is patriotic enough to care whether I spelt the name of a country that rips off it's residents and spends it on, fat pay checks, for people with the talents and skills of monkeys.

Ok, I don't quite get the water return system injected into the manifold, (sounds like a bad idea) I would get rid of it.
I'd say without having seen it that the water is ingested into the chamber when it cools down and creates a vacuum, sucking in the salt water that is strangely injected.
On my project, I'm going to have the radiator in a ss tank that has the salt water pumped in and out, in this tank will also be the trans cooler and oil cooler, with temp monitoring and water level alarm on the dash, That's pretty easy you just use a proximity switch and use the water as the completed circuit, when the circuit is broken the switch is activated to the alarm.
The Viscous fan will draw in air from the deck area via holes in the cover, the other end of the cover will have ducts to the transom under the decks. with slight rise to create a flue effect in drawing out the air, the longer the flue the better the draw about 8 feet is ideal.
Simon.

 

[Poida]

Well Lucas I'm not the patriotic type either. All a country is basically, is a lump of dirt. So somebody's discovered a lump of dirt, called it a name and expect you to die for it.

My pay cheques not bad, but I spend most of it on bananas.

Yeah, pumping water into the manifold is not uncommon and I see your point in the cooling engine sucking the water into the combustion chamber if it was possible but the exhaust is vented to open air so a suction couldn't exist.

Incidentaly not all of the water from the engine is pumped into the manifold just enough to dissipate the heat. Most is pumped into the exhaust, the main benifit of this, is it helps to keep the exhaust fumes down.

Cheers
Poida

 

[AShley5031]

Problems with marinized VW diesel

My BRazilian converted Retipar VW diesel 1.6 is overheating and I really have tried everything I can think of.....reconditioning the head, putting in an orginal (and hard to get) head gasket, changing the fresh water pump and overhauling the Jabsco water pump, with a new rotor, overhauling the heat exchanger, checking the temperature dfference between the inflow and outflow of the heat exchanger...and lots more. It starts fine and then begins to throw water out of the cooling system when it has been running for about five minutes. THis saga has been going on now for 7 months. I have got to the point when I am about to take the engine out of the boat, a 35 ft Bruce Roberts sailboat, and throw it over the side into very deep water!

Before I take this drastic step, please do you have any suggestions?


regards

Ashley