MD2020 raw water pump refurbishment kit

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All The Gear No Idea

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I've identified a leaky pump after finding salt water accumulating in the bilges of my boat. :(

Does anyone know where I can get the seals and drive shaft spares for the sea water pump on my MD2020D?

I know Volvo don't sell them, but hope an OEM solution exists.

The thing is, I don't fancy being mugged for £355, just in effect to replace £20-£30 worth of worn parts!
 
I've changed the seals in the raw water feed pump, using Volvo spares. I last replaced about 2 years ago. The seal for the water is identical to the seal at the other side of the shaft for the oil. Its a simple 'rubber' disc. You need a gear puller to get the gear off, dismantling the pump needs a contortionist. We found the bolts holding the pump on very difficult to access, we cut down cheap spanners to about 25mm long to fit in the confined space. But other than access its not difficult - and we had no problem sourcing spare seals (I'd tell you the part number - but do not have it to hand).

Jonathan
 
Thinking further,

There are 2 manuals for the MD2020, one comes with the engine, is (or was) downloadable and useless. There is a workshop manual which I bought here in Oz, its pretty good (the dealers/service people have it in electronic form, but to protect income I could only buy a paper copy) - but, oddly, omits any detail of the sea water pump. There is separate electronic detail on the waterpump (its not complicated) the dealer here printed it out, its simply a diagram, one page, the first time I changed the mechanical seals. If my dealer has a copy, so should yours. From memory its a fairly standard Johnson pump, they, Johnson, have both the diagram and I assume spare parts. I'm about to leave for a boat show, if you still have problems send me a PM in one week and I'll get you the part number etc.

If you change the seawater side, change the oil side at the same time - so buy 2 seals (they are identical). If the current oil seal is OK (you might damage it when you take it off) but maybe keep it as a short term spare for the future.

Jonathan
 
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Jerry, you are welcome - before getting engrossed, look at the nuts that hold it all together (I think its nuts but they might be studs, do not recall). On our 2020 its all at the 'back' and down at the bottom - consider how to get it apart! Buy a cheap set of spanners cut them to size. 'Crack' the nuts or studs and then use the cut down spanners to wind them off. Once they are cracked its easy - but there is no space (or not on our 2020) hence the shortened, buy cheap, spanners. I think a long socket fits on some but not others (it was not designed with any maintenance in mind).

You are taxing my memory, but I am sure you need to drain the oil prior (so do it when you do an oil, and impellor, change). And gasket paper (or liquid gasket) comes in handy when you re-assemble.

Ours is a 2020D, shouldered cover plate, did not realise the earlier ones used Jabsco.

Jonathan
 
Problem with replacing the bearings and seals is that the seal wears a groove in the shaft so may continue to leak. My local VP dealer refurbished the pump, replacing seals, bearings and shaft. This is less expensive that a new pump and will last a lot longer than just new seals/bearings. Getting the pump off can be a pig of a job. I found it worth the effort to remove everything that is in the way first. For our boat that was batteries, engine mount, speed control mechanism. If you havent already got one - invest in a suitable 3/8 inch ratchet socket set with deep sockets. Then you can easily get to grips with the nuts/bolts at the back of the pump. Beware of other problems though that may be causing the pump to run dry and overheat/damage bearings/seals. This could be caused by a partly blocked exhaust manifold.
 
Hi you have a good chance to solve the problem by just replacing the seawater seal behind the impeller this can be done without taking the pump off and only about £6.00 for a new seal worth a go as you only have a water leak into the bilge
 
Stork III, that's the diagram. The diagram suggests its the 2010 and 2020B and its the same as our 2020D, so guess the C is the same. From memory, jerram, there is no seal accessible from the impeller side (and I cannot see one in the diagram) everything is on the other side and need be removed from the back - so you need take the impeller off and then remove the complete assembly from the back, then take the assembly apart (and you need the gear puller to do that), you could take it home to do this and re-assemble. For the OP, the parts should be accessible from your Volvo dealer. Its not technically difficult but takes time and as BabyBlue suggests you might need to move other bits as well, we did not touch anything else (but its the engine mount that really gets in the way), which is why we used the cut down spanners.

Good luck,

Jonathan
 
Hi Neeves If its a Jabsco pump on the VP2020 you can replace the rawwater seal from behind the impeller without removing the pump from the engine ( I would post the photos if I could of my new seal fitted) You can remove the seal without any fancie tools just 2 small screws into the old seal and pull out of the housing.
Have a look next time you remove the impeller.
ps remember to put the seal in the right way around.
 
Thanks for everyones' input on this! I believe I have the correct kit on order now and am looking forward to fiddling about disconnecting hoses etc after the parts arrive. My pump is accessed from the aft cabin, but i didnt really get a good look at access to the securing nuts/bolts. I've done plenty of mechanical work in the past and am comfortable having a go. I plan to drain the oil as this is due for a change and then will remove the pump (if i have the right combination of tools). I plan to take the pump home and will let you know how it goes.
 
I finally got a slot to get this pump off and have now rebuilt it.
As previous posts have indicated, access to one of the bolts is very tight due to the close proximity of the engine mounting bracket and general lack of space. The solution is to use a stubby 12mm open ended spanner and have a good bit of patience!

The rebuild was pretty straightforward, but you will probably have great difficulty if you don't have access to a gear puller and a bearing press. I was fortunate in that I have a mate with these tools .

You might try freezing the new shaft an heating the replacement bearings, but I'm sure that this route would be difficult.

What we found was that the seals slide over the impeller end of the shaft after the shaft is installed in the pump body. Gently tapping the seals into place was not difficult, so I'd definitely chance changing just the seal with the pump still on the engine next time I get a leak.

The old shaft surface where the seal for the water side was caked in a rusty grime and the seal pretty much disintegrated on disassembly. The shaft cleaned up, but showed signs of wear, so replacement was necessary.

I am now thinking that it might be worth paying the few quid for the seal and changing it every two or thee years, giving the shaft a clean up at the same time. That'd mean no more leaks and no more aggro and expense refurbishing water pumps.

Will see how it goes, but thanks for all the advice!
 
Hi All The Gear
Good news that you have fixed the Jabsco pump and when next time you get a drip in the bilge no need to take the pump off just replace the seal insitu.
 
Maybe I am just unlucky but every time the water pump on my md2020 developed a drip a new seal would not fix it. A new shaft was required each time.
 
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