Yanmar 3YM30 Seawater Pump Removal

[GringoOnStingo]

A sledgehammer is next, unless someone has a calmer and more sensible solution?

And don't you dare suggest a simple Google search for a workshop manual. My Wifi connection keeps dro.....p....ping everytime I have tried to download it.

... storms off in an atmosphere thick with blue language, dripping in sweat and hands oozing with oil-stained blood (caused by the No 13 spanner slipping off the nut with impossible access).

Thanks in advance for any help and apologies for such a grumpy first post!

[Tropic1]

Hi Gringo, Are you trying to take it off the engine or off the bracket? I just removed mine this last summer and removed the entire bracket and then removed the pump from the bracket. also had to remove the pully to get the pump off the brecket. What is wrong with it? if it is leaking water you can just pull the seal out after removing the impeller and then just install the new seal install the impeller and you are good to go. I had to replace the bearings in the pump also.

[GringoOnStingo]

Hi Tropic one. You've hit the nail on the head. It's pissing out water, so it sounds like the seal and a simple job, because even I can manage to get an impeller out without having to kill any bystanders.

I notice that you too have a Maxim 380. Where are you located and are you cruising on her? I have the last one built before Maxim closed their doors and am very happy with her. Have done nearly 14,000 NM on her now and am currently anchored off Grenada.

Cheers

John

[Tropic1]

Hi John. If you've been spraying salt water too long you may have a bad bearing (the first one) on the pump side. check the shaft (turn by hand) to make sure the bearing isn't binding or you might need to replace that which will come down to a sledghammer and a solid vice to hold it(I'm not sure you could rebuild the pump on board, it's a tough job to get the bearings out and in). I neglected mine on the easy side of the boat (behind the head) but when I saw a small leak on the starbord side quickly replaced the seal (the quick and easy fix if you catch it in time). I keep some spare seals on board now plus an entire pump.

I have either the first or second boat built after they streched and widened the hulls in 2004. We aren't anywhere near you, still in Florida (atleast the boat is) I had to pop back back home for a family emergency and hope to get down in time to get to the Bahamas. We are quite happy with ours also, this is my first cat so I have no comparison excpt to monos.

[GringoOnStingo]

Once again, you've hit the nail on the head. The leak has been there for a while and is on the starboard engine, which has all the junk in the cabin above the engine. I am sure you'll understand the natural hesitance in removing said junk in order to isolate the leak. I think it might be time to track down a Yanmar dealer in Grenada and order three new pumps.

[Tropic1]

Don't forget to get a couple replacement seals, they're a lot less painful at the checkout. If it's not binding you might still be ok (loosen the belt and check). The bearings have a rubber seal on them so check first. I would recomend at least one spare pump. I have a dealer back at home whose prices are the best I have found. I was able to get a complete pump, a 3ym30 parts manual and a repair manual for the same price as a pump at other locations. To replace the seal just reach in with neadle nose pliers and pull it out, it might come out in a couple little chunks until you break the rubber loose. then push the new seal in until it's well seated (I put a little grease on the shaft to ease the seal past the slot for the impeller). The problem With my really bad one was the spring around the seal rusted and broke. When I replaces it I reversed the seal so the spring was on the outside of the pump (away from the impeller side) I called the pump company and they said there should be no problem doing it. on the other one I put it in with the spring twards the impeller to see if there would be a difference. Both new seals appeared to have brass springs on them so it most likely won't make a difference this time. Good luck!

[EmeraldCoastSailor]

I am trying to determine the quality of the bearings on my raw water pump and noticed this thread; hopefully this post connects with you. My question is how easily should the pump shaft turn. I can turn the shaft by hand via the pulley or inserting something in the slot on the impeller side of the shaft; it isn't terribly hard but it isn't effortless. The resistance feels smooth and consistent. Maybe it is only my pump side seal that went south?

[a64pilot]

If the impeller is still in the pump it will be very stiff to turn. Remove the impeller to check bearings, spin it and feel for roughness and see if there is any radial play in the shaft ( up and down). A little axial ( in and out) is OK.

[EmeraldCoastSailor]

Thanks for the reply. The impeller was out and I am pretty sure at least the impeller side bearing needs to be replaced. I went Marine Maint in PCB and they confirmed it didn't spin freely enough. Great news is that for $228 plus tax I walked away with a whole new pump. I could be sailing tomorrow but I will paint the brackets before I reinstall. I will replace the shot bearing in original pump once I take it 100% apart and know which elements I need. I also got a couple of impeller side washers and will try to replace every few years or so.