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mrhodes916

Volvo Penta raw water pump

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This past weekend I noticed that my raw water pump has started to slowly leak from the weep hole on the bottom of the pump. I'm hoping that I caught it in time that so that this weekend I can attempt to just replace the seal inside the pump. My question is, can I do this while my boat is in the water? I'm not too concerned about the flow of water when I remove the intake hose because I bought a cheap plug to put in the hose and plug it up. My concern is when it comes time to put the intake hose back on the pump. How easily do those hoses "slip" back on the pump? It doesn't seem like there's a whole lot of slack in the hoses to play with. How much water will be flowing out of the hose and into the bilge while I'm trying to re-attach it? Am I just asking for trouble by trying to do this job in the water?

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I've never changed mine while in the water but imagine that if hose is below the water line that water will flow in. I have heard of people plugging the hose , like you indicated or pinching the hose with a spring clamp to give them time to change out the pump. The hose should go on fairly easy, getting them off can be tougher. Put a coating of a rubber friendly oil on the flange when reinstalling the hose, it makes the hose slide back on easier.

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Plugging the intake hose and making the repairs seems to be a common practice. I've only done it with the boat out of the water but I wouldn't avoid doing it while the boat was in the water. Depending how deep your boat sits in the water will determine how much water would come though the intake hose when it is unplugged.

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Based on info from the folks that have winterized our boat in water....it isn't that your below the water line, its more that there is a suction in place when you take the hose off that causes the water to flow into the boat. I'm told, you can blow the water back out though the outdrive and it will not continue to flow into the bilge. I know when I removed the plug and reattached the intake hose to the pump water was't flowing in.

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I replaced the impellers on my twins while in the water and it is not too bad. I made plugs out of 3/4" PVC pipe with a cap at one end and a coupling at the other; the coupling fits just inside the hose and works great (see pic appended to this message). A little water flows into the bilge during the plugging process but not bad at all HINT: Mark the PVC plugs top and bottom so that there will be NO confusion as to which hose goes where when re-attaching to the housing. I got confused on the first engine, but fortunately had a second one to compare with.

Good luck.

cec

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I have been told that if water is coming from the weep hole on a Volvo that the pump is toast and must be replaced. There are much smarter people than me on this forum so get some other opinions. They aren't hard to change and as you have seen in the other posts it can be done in the water with the right precautions.

Best of luck to you!

Lew

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If the water is coming out the weep hole, it went into the bearing...I also replaced the seal, but the pump squeeled like a cat. I bought a new pump (you have to paint it), and is going to rebuild the old one.

Mine sat a while before I realized what was going on, you may get lucky!

Hoses slide on/off easily....

http://www.ebay.com/itm/Volvo-Penta-REBUILD-SERVICE-Sea-Raw-Water-Pump-21214596-21214599-21212799-/141149802180

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It takes about 3' of water to generate #1 of pressure. As your pump's hose connections are only about a foot lower than the static water level, you will only be fighting back a fraction of a pound of water pressure. The message here is you will have time to react. Pull the suction hose off of the pump and have a plug ready. As far as the discharge hose goes, it will drain back the risers but when they are dry, there will be no head pressure source that would continue to feed water into the boat. Plug that too at your leisure but that flow will stop by itself after a gallon or too.

Water as we know seeks it's own level, and if the suction hose was long enough we could simply pull it up to a level higher than the surrounding sea water level, but there is not a lot of extra hose. Take your time and have the plug ready and you will be fine. Think about The Little Dutch Boy, finger in the dike kinda thing. W

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I have been told that if water is coming from the weep hole on a Volvo that the pump is toast and must be replaced. There are much smarter people than me on this forum so get some other opinions. They aren't hard to change and as you have seen in the other posts it can be done in the water with the right precautions.

Best of luck to you!

Lew

If you catch it quickly you can save the pump by replacing the seal and putting some grease on the bearings. Mine did this 5 years ago and it's still working great with no leaks.

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Just wanted to give a quick update in case anyone finds this information useful for themselves in the future...I replaced the seal in the raw water pump this weekend while my boat was still in the water and it was a breeze. I borrowed from a couple of different ideas and I ended up making plugs out of PVC very similar to what "catalanc" posted above. The only difference was on the plug for the intake hose I used a ball joint instead of a cap (see the image below). Once I removed the intake hose from the pump and plugged it with the PVC, I was able to open the valve on the ball joint and actually blow the water back out through the outdrive to reverse the suction as suggested above by "Stimpy". When it was time to put the intake hose back on the pump I removed the plug and there was no water flow at all. The initial flow of water out of the intake hose wasn't as strong as I was thinking it could be but nonetheless it was nice to not have to worry about any water at all when trying to re-attach it to the pump. Anyway...leak fixed and hopefully no damage to the bearing. Thanks again for all the insight.

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so another words, you connected the ball valve to the intake hose and then connected the discharge hose to other side of the valve?

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I did what is pictured below (from calatanc's previous post) where you shove the end of each plug that has the PVC coupler on it into the hoses. The only difference is my plug that I used for the intake hose had a ball valve on the end of it instead of a cap (pictured above in my previous post). Valve closed...no water running out of the intake hose. Valve open...water starts to flow out of the intake hose but you can then put your mouth on the ball valve and blow the water back through the hose and out the outdrive. This reversed the siphon and prevented water from flowing into the bilge when it came time to pull the plug and re-attach the hose to the water pump. Sorry, I should've taken a couple of pictures as I was doing it. I hope this makes more sense though.

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