MD2020D water pump.

Allan

Allan

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The yacht I'm on at the moment has a MD2020D engine. When preparing to do an oil change I noticed water coming out of the back of the seawater pump, just after the engine was turned off. There doesn't appear to be any coming out when the engine is running. I've ordered a rebuild kit but not sure if it's required or not.
Allan
 
I am trying to sort a similar problem but on mine the water is leaking when the pump is working. Mine started leaking when some fragments of an impeller vane lodged in the heat exchanger causing a build up of pressure. I took the pump out (might not have been necessary) and reseated the water seal and it held for two seasons but needs at least replacement now. Leaks can increase wear on the shaft and if the shaft has any wear then it needs replaced, the only way to get one In UK is a new pump at just under£300 plus vat. I have not managed to dismantle the pump yet but I am not optimistic that new seals will cure it. (I am waiting on better tools to get the shaft out) Johnson who make these pumps seem to offer more spares in USA but there are an awful lot of variants.
On my recent thread on this I gave links to exploded diagrams and servicing illustrations.
 
Allan said:
The yacht I'm on at the moment has a MD2020D engine. When preparing to do an oil change I noticed water coming out of the back of the seawater pump, just after the engine was turned off. There doesn't appear to be any coming out when the engine is running. I've ordered a rebuild kit but not sure if it's required or not.
Allan
Click to expand...

Probably only a question of time before it will leak when the engine is running too.

You may just need to renew the seal but if the shaft is worn you may have to replace that.

Your call really how far you go.. just the seal(s)and impeller or the whole hog including shaft and bearings.

Consider a "Speed seal" kit in place of the existing cover to make future impeller replacements easier.
 
Many thanks for the replies, looks like it will have to wait as there are none available here. I'll sort it out at the end of our journey.
Allan
 
I'm sure all this one needs is a seal and a gasket. Probably worth about three quid but they want to sell a pump for £300+. It would be good if someone knew the size of the seal, I'm sure it will just be a standard one.
Allan
 
Mine leaked & a pair of seals solved the problem. Not difficult to replace on a bench at home
I also have constant trouble with the cover plate leaking after I change the impeller- Annually at least & always remove for the winter
i solve this by using stainless steel cap head screws to get nice & tight plus I use a gasket compound instead of the paper one
 
Daydream believer said:
Mine leaket & a pair of seals solved the problem
I also have constant trouble with the plate leaking when I change the impeller
i solve this by using stainless steel cap head screws to get nice & tight plus I use a gasket compound instead of the paper one
Click to expand...

The gasket is important to give the correct clearance for the impeller. If you must use sealant then use a thin coating of something like Hylomar on the gasket ..Better still though fit a "Speed Seal" cover.
 
Keypart sell the seals for about £3 each. If its a 2020 no need to remove shaft as seal can be extracted and new inserted in situ. Took me about 20 minutes to replace seal once the impeller had been removed. No wear on shaft this time thank goodness.
 
brians said:
Keypart sell the seals for about £3 each. If its a 2020 no need to remove shaft as seal can be extracted and new inserted in situ. Took me about 20 minutes to replace seal once the impeller had been removed. No wear on shaft this time thank goodness.
Click to expand...

Do you know any details of the seal? Please.
Allan
 
VicS said:
The gasket is important to give the correct clearance for the impeller. If you must use sealant then use a thin coating of something like Hylomar on the gasket ..Better still though fit a "Speed Seal" cover.
Click to expand...

The gasket under compression is so thin that I doubt that the impeller is made to such fine tollerances that it makes the slightest difference
 
Vic, I wish you wouldn't keep referring to Speadseal. This is the option i would like to use on mine but they don't make a 2 1/2" version. I'm considering thumb screws or Allen key screws (what's the correct name for them)?
I'm concerned that thumb screws wouldn't compress the paper gasket enough to prevent leaks. Has anyone done this successfully? (or not)
On this subject , what are gaskets made from? Is it possible to cut them from brown paper?
 
Replaced all mine with Allen head screws,£1 on ebay for 10 in A2 ,dont need 316 or A4.
In the past have used gaskets cut from old charts but latest one is made from fine wet and dry paper as its waterproof.
 
ghostlymoron said:
Vic, I wish you wouldn't keep referring to Speadseal. This is the option i would like to use on mine but they don't make a 2 1/2" version. I'm considering thumb screws or Allen key screws (what's the correct name for them)?
I'm concerned that thumb screws wouldn't compress the paper gasket enough to prevent leaks. Has anyone done this successfully? (or not)
On this subject , what are gaskets made from? Is it possible to cut them from brown paper?
Click to expand...

I'm sorry about that. I assumed that there would be one to fit such common engines as the MD 2010/20/30 series.

Not a difficult job for a competent turner to make one. I know someone who made one for the engine in his Pageant and I am sure the sort of thing my Dad would have made.
 
VicS said:
I'm sorry about that. I assumed that there would be one to fit such common engines as the MD 2010/20/30 series.

Not a difficult job for a competent turner to make one. I know someone who made one for the engine in his Pageant and I am sure the sort of thing my Dad would have made.
Click to expand...

Got a speedseal on my MD2030B, but perhaps the OP's donk has a different pump?
 
Quandary said:
I am trying to sort a similar problem but on mine the water is leaking when the pump is working. Mine started leaking when some fragments of an impeller vane lodged in the heat exchanger causing a build up of pressure. I took the pump out (might not have been necessary) and reseated the water seal and it held for two seasons but needs at least replacement now. Leaks can increase wear on the shaft and if the shaft has any wear then it needs replaced, the only way to get one In UK is a new pump at just under£300 plus vat. I have not managed to dismantle the pump yet but I am not optimistic that new seals will cure it. (I am waiting on better tools to get the shaft out) Johnson who make these pumps seem to offer more spares in USA but there are an awful lot of variants.
On my recent thread on this I gave links to exploded diagrams and servicing illustrations.
Click to expand...

If you go along to your local bearing factor they will have seal kits which include a very thin stailess steel tube that will fit over your shaft and which the replace seal will run on. Shaft wear from seals is a common problem so these kits are made in a wide range of sizes. Have a look at http://http://www.skf.com/us/products/vehicle-aftermarket/automotive/specialty-parts-and-programs/speedi-sleeve-shaft-repair-kits/index.html
 
Sorry, should have mentioned that mine is an MD1.
VicS said:
I'm sorry about that. I assumed that there would be one to fit such common engines as the MD 2010/20/30 series.

Not a difficult job for a competent turner to make one. I know someone who made one for the engine in his Pageant and I am sure the sort of thing my Dad would have made.
Click to expand...
 
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