BMW marine engine

ariel · Landlubber Joined: 28 Sep 2009 Posts: 1 Location: Alaska

Hi All, just aquired a Lord Nelson 41 , 1983 ventage with a BMW marine D 50 engine and Zf transmision. What are the weak points of engine & transmision? What is the expected life given proper mantiance? What upgrades should be made to this package? This is the original eng. with 2100 hrs . Thanks.

mimoza · Posted: Mon Oct 19, 2009 1:21 pm Post subject:

I'm not familiar with that tranny, but the D50 should last many, many more years. It would not be surprising to see this engine go well beyond 10,000 hours. 2100 is definitely a very low number for engine hours. However there are several things that will help it live to the ripe old age it deserves.

1) It's always good to have an analysis run on the oil in the crankcase. This will point out most deficiencies in the engine, and should be part of a full survey suite.

2) Proper maintenance. Oil & filter change every 100 hours or three months, whichever comes sooner.

3) Don't idle that engine too much. Diesels like to work hard. Charging batteries does not qualify as "working hard." Idling diesels tend to build up carbon deposits, and they are not good for the engine.

4) Run your engine at ;east every couple of weeks, even if it is only idling. Especially if it is in salt water all winter, the raw water must be flushed out periodically to keep the exhaust system from corroding. There are plumbing tricks that can let you flush the salt water from the raw water system before shutting down, replacing it with fresh water from your tanks. I recommend them, especially if you anticipate longer periods away from the boat.

5) Clean air and clean fuel: Use good filters for the air intake and the fuel system. Water separation capability is a "must" in the fuel filter system. In the U.S. clean diesel is not a problem, but in other parts of the world....

One more thing I can't fully address, and that is the effect of biodiesel and low sulfur diesel on this engine. There are fuel additives (Stanadyne is excellent) that fix most of the known issues with engines of older design, chief among these being fuel lubricity. Low sulfur diesel has less lubricity than high sulfur diesel, and lubricity is required for your high pressure fuel pump to have a long life. Don't get the 8 oz. Stanadyne. It is for cars and trucks and has less of the additive you need.

You should be good to go for many years - a good deal longer than this boat has already been around. Still, you should find a good diesel mechanic and have a chat. It's good to have someone to call before you need them - but my guess is that you will never need to make that call.

Congrats on your Lord Nelson.

warmrain · Posted: Tue Oct 20, 2009 9:24 am Post subject:

All good advice Mimoza!

Yes, a diesel should really be run at 80% of it's continuous rated RPM 80% of the time in order to assure full life span.

And of course regular oil changes, especially at the end of the season if the boat is not going to have the engine started all winter.

And yes, for older diesels designed in the era of high sulpher fuels, a lubricity additive (e.g. Stanadine Performance Formula) is essential to long (mechanical) injection pump life.

http://www.stanadyne.com/view.php?id=74

~Cars

jonehaze · Landlubber Joined: 13 Jan 2010 Posts: 3

I can't help you with the engine but some tips on the tank. You should drain and clean the tanks in order to inspect them. That is the only way you will know what shape they are in. If they have been kept clean and free of water they could be in excellent shape. If they have been neglected they could be rusting from the inside out. Much also depends on how they are mounted. If they are in the open and mounted on material that does not hold moisture they could very well be in good shape.However, if they are surrounded by foam or mounted against wood they could be in bad shape. Can't be more specific than that. You just need to inspect them very carefully.