Oil change BMC 1.5 diesel

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Graham_Wright

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www.mastaclimba.com
The sump drain pump is totally inaccessible and there appears no way to make an access.

The dip stick tube bore is around 7mm diameter. I will try to suck through that but, with a Ø5 bore in the suction pipe, it will take forever and will doubtless be blocked by sludge.

Has anyone found the courage to create a new access plug with the engine in situ? The sump metal will presumably be too thin to allow a tapped hole although maybe there is an oval widget which would make it possible.
 
Run it until hot and suck it up through the dipstick.

The reality of sludge as such is not going to happen unless there's something very wrong with your oil change interval!

Push the tube until it stops and pull it out a centimetre so it doesn't suck on the bottom of the sump pan! You could try a flushing oil between draining and refilling with your new engine oil if you suspect there will be stuff left in the engine.
 
Do as No Regrets says. Getting the oil hot is the key.

The pump on mine was connected with a flexible pipe to an elbow which was screwed into the hole where the drain plug would be if the engine were in a vehicle. The sump metal is thin and the hole for the plug is actually a thick piece of metal which is internally threaded and welded to the sump.

EDIT: Oops, wrong motor. It is the Watermota Sea Panther that I had on my last boat that had the flex tube from sump to the oil change pump. The BMC Captain on the previous one had a rigid metal tube. After using the pump a few times, I bought a Pela (actually Seago) vacuum extractor and sucked the oil out through the dipstick hole.
 
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What oil are you using to have all this sludge?
Even if the oil is cold, the Pela should suck it slowly, once you have pumped the Pela to a vacuum, you should just have to wait.
If your oil is that relauctant to flow up a 5mm pipe, it is probably not ever so keen at getting around the bearings.
One of my yanmars, I took the sump off in situ, cleaned it out and then tapped a drain hole at the back.
I found a few bits of solid gasket goo in there, that sort of thing might be blocking the Pela?
 
Ooohh.. the dreaded BMC 1.5. Had one in my boat when bought years ago. It took me ages to suck the oil out when I got it - it was like sludge. I reckon the oil had never been changed for several years, because it was really difficult to drain. Had to dump it after a year, took ages to start and left a smokescreen behind me when motoring, even after I'd spent over £500 trying to get it sorted. Fitted a Beta 25hp which has been brilliant.
 
lw395 said:
What oil are you using to have all this sludge?
Even if the oil is cold, the Pela should suck it slowly, once you have pumped the Pela to a vacuum, you should just have to wait.
If your oil is that relauctant to flow up a 5mm pipe, it is probably not ever so keen at getting around the bearings.
One of my yanmars, I took the sump off in situ, cleaned it out and then tapped a drain hole at the back.
I found a few bits of solid gasket goo in there, that sort of thing might be blocking the Pela?
Click to expand...

There wasn't any sludge. In fact the oil was in pretty good condition. I couldn't run the engine to warm it up first as the oil filter was off (that's another story).
 
PetiteFleur said:
Ooohh.. the dreaded BMC 1.5. Had one in my boat when bought years ago. It took me ages to suck the oil out when I got it - it was like sludge. I reckon the oil had never been changed for several years, because it was really difficult to drain. Had to dump it after a year, took ages to start and left a smokescreen behind me when motoring, even after I'd spent over £500 trying to get it sorted. Fitted a Beta 25hp which has been brilliant.
Click to expand...

If you had a good 'un they were excellent engines, would go one forever and a day. For its time (1970's) it was one of the smoothest and quietest small diesels you could put in a boat No worn out engine will start or run well, even a Beta 25. Lets see what yours is like in 30 years time!
 
oldharry said:
If you had a good 'un they were excellent engines, would go one forever and a day. For its time (1970's) it was one of the smoothest and quietest small diesels you could put in a boat No worn out engine will start or run well, even a Beta 25. Lets see what yours is like in 30 years time!
Click to expand...

Agreed mine never let me down really though I forgot to give the cooling system it's annual flush and had heating problems till I got it done ( you try finding radflush in France on Sunday) otherwise it was great. After a 24 hour run it would start with no preheat up to a week later. If I still had one I would fit a bigger alternator just because we all use more power now.
 
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