BMW 3 Cylinder Diesel Engine

[Forbsie]

Does anyone have any experience/knowledge of these engines. Any good? Are spare parts easy to get? Any idea about what hp it would be? I've been offered a marinised one for £1000 which would be versus another option of a BMC 1500 for £300 but which I would have to ship from Aberdeen and then marinise.

Any advice gratefully received.

BTW, I bumped into Boatone at the Trad Boat Rally today. He hasn't touched a computer for 48 hours and is looking very well for it ... apart from the twitch that is. ;o)

 

[Chris771]

Don't know anything about BMW 3cyls. However, I would think that a BMC 1500 is getting a bit long in the tooth and they prefer to wear their oil rather than hold it, not much power either you'd be lucky to see 30 bhp.

Why not marinise a small Ford? I did a 416 from an Orion 1600 about 10 years ago. Quite straightforward and I must have done a good job because it lasted me 6 years and the guy who has the boat now has never complained. The later 418 1800cc engine is also quite plentiful and similarly easy to marinise. The only downpoint is that the alternator in road form is mounted under the block, but there are 3 tapped holes on the upper starboard side and I made a plate and bracket to support the alternator and also made a threaded stud adjuster which allowed the fanbelt to be adjusted using just one hand (A great asset in a tight engine space). For purists the alternator now receives a secondary pull from the crank, not a primary pull as God intended, but that never seemed to make any difference, and it was nice to know that the engine could be well submerged before the electrics were lost.
The only other part that needed changing on the block was to remove the vacuum pump and fit a Ford made cover from Hendy Lennox at Havant. The flywheel was a bit light for low speed running so I made up a rotating mass (big weight) registered onto the flywheel to approximately double it's weight at about 18mm thick. The engine then ran smoothly at 600 rpm and would happily drive at 700 for gentle low speed manoeuvring. The remainder was just pipework, the only awkward thing was mounting the starter as the engine to gearbox adapter plate from Watermota was not drilled quite correctly. A bit of judicious filing solved that and it only ever came loose once in 6 years, cured by plain nut locked by a nylok on each bolt.

These small Ford blocks are a bit noisier than the latest generation of small diesels, but are cheap and reliable. Good engine soundproofing will cure noise. The Heat exchanger was by Bowman and the raw water pump a Johnson, on the front crank pulley which needed 3 holes tapping through it. The front pulley bolts on these engines are unbelieveably tight at a few hundred ft/lbs and need the flywheel locking and a 32mm socket and a long bar to undo. They usually come undone just after you have convinced yourself that you must have twisted the crank in the process. All the special tools required can be made at home (if you have welding gear)and are shown with dimensions in the Haynes Manual. (I made all mine).

Whatever you buy I don't think you want a BMC. AMC at Preston have just dropped them without even bothering to stock spare parts, and they were importing new ones from India as recently as 2 years ago. The small Fords should make about 45 and 50 hp at 4800 rpm respectively. I think mine made 40 hp at 4000 rpm, the low max revs ensuring a longer life.

Chris



www.impact-computers.net/boat/cruiser.htm

 

[Forbsie]

Thanks for the advice, Chris. The problem is where do you get these engines. I've been phoning around for weeks trying to get one. The engine in there at the moment is a 2.1 litre Ford (Peugeot) and as I've mentioned in previous threads, I don't think it's ever been run in the boat - too big and a total dog's dinner. I also have a Sonic 100 stern drive and so am looking for 40hp max. I also am no engineer (yet) and so will have to get a yard to do most of the work although I have a very good one at cheap rates right where I'm moored.