Anyone have knowledge or experience with BMW D50 to share?

[matan]

I would like to replace the oil pressure sender switch on my BMW D50. The onethat i am taking out does not have any markings. Harz diesel does not still supply this part. I can get others from the auto supply shops , but I NEED TO KNOW THE OPERATING PRESSURE of the engine. Anyone out there can help me?

[Oceanride007]

No I can't, but in general 2 Bar is normal operating pressure, would think oil warning low would be .5 Bar, max operating pressure would be 5 Bar.
Here a bar is 14.7 psi or 1kg/cm^2. Not sure what thread it is.
Think if you went to Hatz, would think any of there senders would be fine if thread size is correct. To be on safe side I would test it for operation, do not know if nc or no (Normally open) check it.

[newhaul]

Originally Posted by matan

I would like to replace the oil pressure sender switch on my BMW D50. The onethat i am taking out does not have any markings. Harz diesel does not still supply this part. I can get others from the auto supply shops , but I NEED TO KNOW THE OPERATING PRESSURE of the engine. Anyone out there can help me?

shoot an email to v12 engineering they are the bmw marine dealer fro north America they will be able to direct you .
Home - V12 Engineering
They have helped me a lot in the past.

[matan]

The water light andthealarm that i had fitted came on after 30 minutes of motoring. Again. This time there was water coming out of the exhaust. The motor gave no evidence of being hot. There was perhaps more steam coming out with the exhause. Or this couldhave been theafternoon sun. What wouldcause the wareralarm to sound if there was notan overheating problem?
How should i flush the engine in case thereis a blockage.

[Oceanride007]

Matan, Are you saying you have a Jacket water high temperature Alarm now?, whereas you previously had issue with the oil pressure sender.
Do you have one of those Infrared Thermometers to check around the Engine, should be about 60DegC at the JCW pump. Is your Fan belt in place. Is your sea strainer clear, if you have flow out the exhaust then you don't have issue with air lock at the pump. Anyway check the above, next step would be to replace the impeller. When you buy the impeller get several, my experience the supply is running low.
If you have a HW service would check the JCW in out temp to determine if JCW pump is a problem. All the above assumes a Engine with Closed circuit Jacket water.

[matan]

I checked the impeller before i posted but it looked like new. We have located the problem as being inthe wiring behind the board that has the ignition andwarning lights. Not sure which is loose but we can move the harness and get everything working.
I replacedthe oil pressure sender and that cured the problem on that side. I think that we might have a water blockage somewhere.. i will be back flushing the raw water system. Any suggestions as to where to disconnect the system and then attach a hose.

[Oceanride007]

If you asking me, no I don't, I don't know if your engine has treated closed circuit water or is raw water cooled. My Engine has closed circuit, the only place I can imagine that has blockage is on the connection to the exhaust. If your Engine is raw water cooled it would have Anodes and it is conceivable that a anode has fallen off and gone somewhere it should not have.
If you disconnect the outlet from SW pump, a little start of the engine should indicate if you have any issue before the pump. Taking the connection off the Exhaust pipe, may provide you with a way to back flush.


This message was written Yesterday, got caught in some kind of loop.

[matan]

When we took the thermostat out we found the housing to be half full of a black gunk. Now we would like to flush the entire cooling system. Any suggestions? I would like to fill the cooling system with vinegar and then circulate it with a pump from and to a bucket By filtering the intake ofthe pump the gunk should remain in the bucket. Where should I open the cooling systemto commect the pump, and where should the bucket be positioned to receive the outflow.

[Oceanride007]

Matan, Don't do it, not at all, that black gunk is your friend, its called plumbago, its largely carbon resulting from corrosion of cast iron. It is working like an insulating layer to stop more corrosion. At least pause, ask your friends down at Hatz, see what they reckon. Am more familiar with plumbago in Cast iron condensers, Heat exchangers and the like. Not sure about in a Engine. Removal of Plumbago will enhance internal corrosion till a passivating layer (of it) builds up again.

[matan]

Originally Posted by Jim Cate

OUr previous boat had a D-35, which is indeed just a two cylinder version of your D-50. Ours was raw water cooled, and that was the only issue we had with it: that is,salting up of the cooling passages. Ran reliably, had >6000 hours on it when we sold the boat.

At that time (2004) we were able to get parts in Oz from Hatz diesel. Dunno if that is still true... I'd suggest calling them!

Jim

How did you unblock the cooling system. I amhaving this problem right now. We removed the thermostat housing and found that area to be half blocked by a black sludge. This was shifted easily by soaking the housing in vinegar. I am wondering how to backflush the engine? Where would you connect the pressure hose and where would you open the cooling system for the water too exit.

[matan]

Wow, plumbago! This stuff was a thick gooy mess. It was enough to blockthe flow. The temperature alarm is sounding when we use the motor for a half hour or so. The new annodes are in place but that does not mean that bits fromthe old onesare not somewhere. I am hopingthat a backflush with fresh water will solve the problem. I wouner where is the best place to connect a fresh water hose and where to opwen the system to allow the gunk to come out? Any suggestions.

[matan]

Originally Posted by Jim Cate

OUr previous boat had a D-35, which is indeed just a two cylinder version of your D-50. Ours was raw water cooled, and that was the only issue we had with it: that is,salting up of the cooling passages. Ran reliably, had >6000 hours on it when we sold the boat.

At that time (2004) we were able to get parts in Oz from Hatz diesel. Dunno if that is still true... I'd suggest calling them!

Jim

I have a yacht with the D50. Raw water cooled It is sending theheat alarm after about 20 minutes running. We have replaced the thermostat and sender. Still have the problem. How did you cure the saltingup of thecoolingpassages.
Jim. Fremantle Western Australia

[Jim Cate]

Originally Posted by matan

I have a yacht with the D50. Raw water cooled It is sending theheat alarm after about 20 minutes running. We have replaced the thermostat and sender. Still have the problem. How did you cure the saltingup of thecoolingpassages.
Jim. Fremantle Western Australia

I did periodic acid (HCl) washes, circulating a pretty strong solution through the engine for a period... until the burbling noises from the engine innards stopped.

Kind of a PITA, did involve use of strong reagents with significant health and safety issues, but it worked.

I've heard that a product called Ryd Lime or sumpin like that will do the job with less hazard, but no personal experience to share.

Jim

[matan]

Did the HCL affect the oil cooler? I would like to do the flush but worry about any seals in the oil cooler. Also just how did you set up the flush? I have an idea to use a bilge pump so as not to run the engine. Did you do it withthe engine hot or cold? What concentration hcl did you use?

[Jim Cate]

Originally Posted by matan

Did the HCL affect the oil cooler? I would like to do the flush but worry about any seals in the oil cooler. Also just how did you set up the flush? I have an idea to use a bilge pump so as not to run the engine. Did you do it withthe engine hot or cold? What concentration hcl did you use?

No noticeable change in oil cooler.

I used a big (5+ gallon) drum full of (IIRC ~2:1 diluted swimming pool HCl. Raw water intake hose in bucket, exhaust water in bucket. Run engine ~30 seconds to circulate, turn off and wait for noise to diminish, repeat until burbling noise does not return. Lots of gunk will come out with the exit water and settle to the bottom of the drum.

Oh, BTW, be sure to remove the cooling circuit anodes first!

If you don't run the engine, you;ll likely need to remove the impeller from the raw water pump... I don't think a bilge pump will generate enough pressure to force water through the impeller.

I don't think my method is anything special... but I did it a few times over the years and had no dire results that I was aware of.

Jim