Brown Sugar in Diesel

[Ex-Calif]

The concern here is for the sugar to melt and then solidify in any oil passages.

After 40 hours of running this would have already happened were it going to. It hasn't. change the oil and filter again and move on with life.

I would vote strongly against pouring water in the oil filler. The only thing pouring any liquid into the filler will do is have that liquid drain into the sump. The only way to circulate that liquid is to turn over the engine. If you started the engine with water or any other solvent in the sump you are taking a huge risk IMO. Even turning the engine over with the starter is crazy.

If flushing the oil galleys is desired new oil seems as good an agent as any.

Oil and water don't mix
40 hours of running time is a pretty good test.

[bobox]

Sounds reasonable. I think I'll run the engine with the new oil change for a number of hours and then do another oil change and see if I find anymore grains of sugar. I can reach all the bolts on the sump so I think I have just enough clearance to get it off and clean out the strainer.

[Dockhead]

Originally Posted by bobox

Sounds reasonable. I think I'll run the engine with the new oil change for a number of hours and then do another oil change and see if I find anymore grains of sugar. I can reach all the bolts on the sump so I think I have just enough clearance to get it off and clean out the strainer.

If I were you, I would do multiple oil & filter changes -- as in many, many --in rapid succession, and I would by all means get that oil pan off and thoroughly clean it out together with the strainer. I would think that most of the sugar is probably lying on the bottom of the oil pan (sugar is very dense compared to oil), and/or stuck in the strainer. If you get an obstruction to oil flow because of the sugar grains, or an obstructed oil filter, you will have big problems. If the oil filter gets clogged with sugar grains, pressure will go up and a bypass valve will actuate, which could let the grains get into the pressure oil system, at which point all bets are off.

As you do your oil changes, you might consider cutting open the filters to monitor whether you're still getting sugar in there. You might also consider a follow-up oil pan drop or two. If you're lucky the sugar will disappear after the first clean-out.

I had not grocked before that you have already put on 40 hours. If you've got 40 hours on with sugar in the engine and it hasn't seized already, that is a pretty good sign, I think, that the sugar has not gotten further than the oil pan.

Good luck and let us know how it turns out.

[osirissail]

If getting enough clearance to be able to remove the oil pan is a problem, as it is my boat - I solved the problem by making an "A-frame" of two pieces of 4x4 wood beams bolted together at the top with a 2x4 wooden beam horizontally across to finish the "A." I placed that over the end of the engine with the clearance problem and used a "come-along" to life the rear of the engine a few inches to get the necessary clearance. *Of course I disconnected the prop shaft flange from the transmission, any affected engine mounts and loosened any wires that might be stretched too much.
- - The idea of using the "A-frame" rather than a cross beam was to not overload any vertical boat walls or other parts as the feet of the "A-frame" rest on the hull of the boat.

[daddle]

I'd pull the engine out and remove the oil pan. Inspect, clean, then do all the filtering and oil changes recommended above. Paint the engine room and replace all the hoses while the engine is out.

[Therapy]

I'd do the oil change and run it.

Especially since you state 40 hrs already.

[Yachts66]

Well, I feel like we've kinda beat this poor subject to death , but at least we can all agree sugar of any kind in your oil is not a good thing. I tried to find the normal operating temperature of oil in a diesel engine and came up short. It would appear to be somewhere between 120 and 140 degrees C. Certainly high enough to boil water, which stands to reason because you generally want to run your diesel long enough to get condensation out of the oil. Now, the question remains, will the brown sugar dissolve in oil at any temperature? To that I could not find a good answer. Certainly it easily dissolves in water and since condensation is common in the marine environment would that mean there would be enough water in the oil to dissolve at least some of the sugar? My guess is maybe, but given the value of a typical marine diesel do you want to chance I'm wrong? I wouldn't.

I think pulling the oil pan is a great idea and certainly no small undertaking in most boats. Makes a lot of sense to go ahead and paint the bilge while your at it too. Having gone to all that trouble, why not install a thrust bearing and CV drive link so you don't have to fool with precise engine alignment any more! Heck of an idea that.

Regards,

Thomas

[bobox]

I contacted Westerbeke and they were not overly concerned that it would damage the engine. They recommended, as others here have, to simply do a couple of oil changes. As dockhead pointed out the sugar is much denser than oil so it settles very quickly to the lowest point. I found no sugar in the oil I sucked up through the dipstick, only in the oil I took out of the oil filter.
I think I can get the sump off but not having done it before am worried I may not be able to get it back on for whatever reason (eg it may need a new gasket or something) so will probably wait till I'm in a Marina. I'm living off the hook at the moment so cant risk being in a situation where I'm dead in the water.
Thinking about the actual act of putting sugar in a boat engine its not far off cutting the brake lines on a car in my opinion. If the engine failed coming through one of the bars along the coast here the boat could easily come to grief and my young son and partners lives would have been put at risk.
Thanks for all the input and debate.