Seawater pump / sea water pump / raw water pump Volvo MD2020D. Johnson pump. This video is about Volvo Penta MD2020D Raw Water Pump Water Seal (installed on a Bavaria 32 yacht)
This video is an absolute gem. There are hundreds of videos and writeups on how to change the pump and how to rebuild it. And most implied or said that in order to change the water seal you needed to remove the pump. If I hadn't seen this video I would have been unnecessarily removing my pump and possibly creating other problems. The key trick shown in this video is how to push your water seal forward by making a little tool out of some kind of wire and inserting it in the vent hole behind the actual impeller housing to push the seal forward enough to pinch it with a pair of needle nose pliers. Thanks a million for this video.
I can only agree with below comments. Up there with the best videos I've seen on fixing things around the boat (or house). Very instructional. I replaced it yesterday on an Volvo MD2030D ( build in 2004) and the seal that came out was exactly the same as in your video. The inside spring was broken. I used a Johnson seal (for F35 or F4 impeller pump) from the Dieseldokter near Amsterdam which was half price the Volvo one. Fits perfectly and no more leak. I hope I'm good for another 17 years ...Thank you very much for saving me hundreds of euros and the pleasure of fixing this myself.
Thanks so much for this. I just did the replacement according to your method and probably saved myself a four figure sum - Volspec wanted to remove the engine to fix the problem! Everything now working fine. A couple of points As you mention, a coat hanger is probably not stiff enough to pole out the old seal, and I used a piece of galvanised wire. The seal was completely perished, so I was able to remove some of the old seal by carefully picking away with small long nose pliers. No need to remove the hose as shown in your video. Thanks again!
Fantastic video and information. I need to change my seal and was thinking of trying it that way, without removing the pump. Now I know I can, so won't wait till the season is over!
thanks for this video. It is precisely what I needed. I am off to my boat tomorrow to try your technique as we have a tiny spurt of water coming out of the back of our pump (2030D). The thought of removing the pump was a bit too scary for me!
Good idea for a quick fix and good info on the seal. I love ingenuity however 2 points: what about the bearings? no way to access them with this fix, they might need some lube or worse, replacement. Secondly if you are leveraging this idea, Its good to look for a diagram on how your specific pump shaft and seals go together. On my VP TMD30a there is a o ring on the other side of that seal that is meant to help any escaping water to drip away from the seals and down the weep hole. So I've been told, Its usually good to replace both seals at the same time but logic tells me the one facing the oil isn't going to degrade that spring like the one facing saltwater. Next leak might be oil but hopefully this seal will keep water out. I'm going to give it a go. Thanks for posting this trick.
Leave the O rings and everything else - this ‘trick’ is only concerned with the water-facing seal which tends to fail due to salt water destroying the garter spring. The oil-facing seal fails less often. It won’t help if you have a bearing problem but you probably won’t … the common problem is water dripping from the weep hole and this ‘trick’ solves that. I’ve done it a couple of times on my pump.
Hi, I came across your very helpful video as I am looking to replace a weeping seal, I too have a 2004 Bavaria 32. A couple of questions, is there a backing plate between the impeller and the seal? I have seen another video that has one but I think that could be a different pump. Is there swear plate inside the pump and if so did you have to remove that. Brilliant video, well done. Steve
The MD2020D was supplied with at least two different versions of the raw water pump. Mine is p/n 3580944 which seems to be a Johnson pump (not Jabsco). I think the earlier engines had a Jabsco pump. There is no backing plate. This is unfortunate, perhaps, as it means that the bronze pump housing wears rather than a wear-plate, but there is definitely no plate on mine. The impeller is in direct contact with the water-facing seal.
Great video. Many thanks. I also have a Bavaria 32 (2002) which is leaking water from the raw water pump. Any idea where I can get a GACO DPSM 12 24 7?
Thanks David. I think the seal is a standard engineering one (not a specialist marine one) and a Google search should throw up options. Mine came from Keypart but they weren’t specifically for the MD2020 job; I had them in stock from a rebuild kit for the pump on my last boat, which was a different model but, luckily, the Gaco seal was the same one. Keypart will sell them but, doubtless, at an inflated price. I did have a search a few years ago and from a non-marine seals supplier they were very cheap. Good wishes.
The Gaco website is gacoseals.co.uk and they direct you to Orinoco Bearings in Leeds (www.orinocobearings.co.uk/seals.html) who say that they deliver orders of 'any size'. So suggest starting there.
