BMW D12 engine

domahawk

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Have recently bought a boat with a D12. Works well but needs some TLC such as a leaking water pump and control panel swithces. Any idea of a UK based BMW parts supplier? /forums/images/graemlins/confused.gif
 

Goldie

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I had one in a boat a few years ago but all I can remember I'm afraid, is that the engine was based on a Hatz generator engine, might that help? The only other thing I can suggest is trying to find what other boats had them fitted and then approach either the builders or any Owners Association. From memory, I think some of the Sadlers (25 or 26?) might have been fitted with the D12.
 

Avocet

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Welcome to the happy (and select!) band of D12 owners! (yes, me too)!

This is a good site for everything to do with small BMW marine engines:

http://wavelength30.zxq.net/BMWD7.htm

Also a Yahoo Group for them:

mailto:bmwmarineengines@yahoogroups.com

Official source for spares in the UK is PH Marine:

Peter Humphris at P H Marine,
Val Wyatt Marina, Wargrave, Berks RG10 8DY, UK, tel +44 (0)1189 404419,
fax 01188 404890, email peter.ph-marine@talk21.com

That said, any bearing factor should be able to get you replacement seals for the water pump. Make sure you get stainless or bronze garter seals inside the lips though!
 

TheBoatman

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Over many years of boating (40+ years) I have driven boats with many engine types in from 2Hp outboards to twin 1100 SHP in-boards , and I can confidently say, from direct experience, that the absolute worst engine I have ever had under me was a BMW (Hatz) D12!!!!

D12's leak (everything), rattle bits off, refuse to start, Strip Ali threads, sound rough, have less than 12 hp, despite manufacturers claims ~ in general, I wouldn't give this engine house room!

I would have willingly used it for a mooring weight if only it had been heavy enough!

The best thing I every did was to change it (exchange it) for a Yanmar GM20.

Peter
The Boatman.
 

T_C

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I second PH Marine. I used to have a D7 in my Sadler 25, it and I had several battles, most of which it won before I finally replaced it. PH Marine offered a very good mail order service, and if they had it, I normally got the bit I needed next day. The one exception being a week at Gweek once waiting for a new head gasket.
 

Avocet

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Must admit that while I don't much like it, I don't think they're THAT bad! Ours was fitted in 1989, then used for a few years before the boat sank. On raising the boat, the seawater was emptied out and it was given a few oil changes by the previous owner, but never stripped. We bought the boat in the early 1990s and since then, although I've had the head and barrel off, I've never fully stripped it!

It has never leaked and I've never stripped any of its aluminium bits. The alternator was knackered following its immersion but the alternators were lousy on them anyway and I don't think many of them still have their original alternators now. We bodged a car alternator onto ours.

For a marine engine, it has a number of good features. For a start, it has no oil filter or pump. There is a roller bearing crank and everything else is just splash lubricated. You also don't need many tools to take it to bits and it is capable of being hand-started (if you're strong enough or if it's already warm)!

I hate the fact that it's very heavy and I'm not at all sure it puts out 12bhp (more like 10, I think) but it has never let us down. It's horribly harsh and noisy, but I guess most single cylinder units won't be that smooth! The only real trouble we've had with it was when a faulty anti-sypon valve filled the chamber with water and the piston rings rusted into the bore, and I'm not sure I can blame the engine for that.
 

FullCircle

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[ QUOTE ]
I second PH Marine. I used to have a D7 in my Sadler 25, it and I had several battles, most of which it won before I finally replaced it. PH Marine offered a very good mail order service, and if they had it, I normally got the bit I needed next day. The one exception being a week at Gweek once waiting for a new head gasket.

[/ QUOTE ]

Thirded. My D7 was a pox on the ownership of my Evo 25. I eventually tracked down dumper parts, which broke just as often, but at 1/3 of the price. In he nd I sailed round for 2 seasons without it.
Not BMWs finest hour.
 

Sheerline

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My D7 was adequate in our 25ft yacht when new (although the specs show 6hp max, not 7).

But it was a right pain for the last 20 years.

Best thing I ever did was spend the money and get a new Nanni.

The BMW was one of life's mistakes.
 

davey

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Over many years of boating (40+ years) I have driven boats with many engine types in from 2Hp outboards to twin 1100 SHP in-boards , and I can confidently say, from direct experience, that the absolute worst engine I have ever had under me was a BMW (Hatz) D12!!!!

D12's leak (everything), rattle bits off, refuse to start, Strip Ali threads, sound rough, have less than 12 hp, despite manufacturers claims ~ in general, I wouldn't give this engine house room!

I would have willingly used it for a mooring weight if only it had been heavy enough!

The best thing I every did was to change it (exchange it) for a Yanmar GM20.

Peter
The Boatman.

Ah but if it is so bad that is a bonus as it is less likely to be cannibalised by thieving toe-rags. You know the type? Heroin addicts and drugs and booze come first so they do not do their shopping in the normal way. The Yanmar 1GM10 is IMHO only any use as a mooring weight because it is a first class thief-magnet. First the OEM elbow rusts through but remember that its owner puts drugs and booze at Priority One. Next the exhaust port rusts through. With a new head at £800 and the OEM elbow at £200 he goes on an alternative-shopping-trip. Whilst he's at it he steals the seawater pump, the lubricating oil pipes and banjo bolts (the banjo bolts cost £11 each and there are four of them!) Over £1500 worth of parts get taken which in effect puts the engine beyond economic repair. Now is the BMW really so bad? Maybe the answer is to have a little Dong-Feng engine or something really undesirable as when thieves are about worse is better! In Devon and Cornwall piracy and thieving are still a way of life for a lot of people and allegedly about ten years ago someone tried to wreck a bulk carrier at Bideford Devon (A false light was set and the real light was covered-up however the skipper was not fooled) Allegedly the police had a good idea of who had done it but nothing could be proved. The suspect was someone who should have known better but the laws of libel prevent me from saying who the suspect was. Normally he would wear a blue jumper, nod-nod wink-wink! Take care!
 

davey

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The base engine is a Hatz and the industrial engine parts can be obtained from Bryco at Daimler Road. The flywheel generator was extremely bad as regulation was achieved by shorting-out a tertiary winding with a thyristor. This created voltage spikes and radio interference. The late George Huxtable had a superb article on his website that showed how to adapt the engine to take a car alternator. The Renault Couach 11 HP marine engine was also based on a Hatz but it was not quite the same as the BMW D12. Allegedly the flywheel generator can be rehabilitated by using a different type of voltage regulator. As far as I know the new regulator regulates without using the tertiary coils. A small increase in horsepower is obtained as the tertiary coils no longer create a drag.
 

adamstjohn

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I had one too, ph marine is the place to buy bits, we bought all we could then gave up
And replaced it, I love old things but hated this one, always seemed to stop at the most inopertune moments, locks normally, the hand start was its best point and sadly missed, we have been known to use all battery power and not have enough left to start leaving a sail home, hey ho, lesson learnt.
 
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