Water pump malfunction on our 3 year old Rinker 340 with Mercruiser 350 mags

OldDogNewTrix

Last winter our marina tech noticed that the starboard water pump needed replacing and they did that during the winter maintenance. Yesterday, in the middle of our 2 week vacation, the engine alarm sounded as we were on plane 15 minutes out of Gananoque on our way to Picton then Bellevile ( MT, you'll know this area exactly). I shut down both engines, then read the code on the Vesselview, the port engine had overheated, sure enough, it was at 200 degrees! Luckily I was in a large area of open water in the main channel south of Wolfe Island so I popped the engine hatch and had a look. Right away I noticed the serpentine belt lying in the bilge. First thought was oh great, I have the spare one from last winter when they put a new one on the starboard engine. Once down there, I realized it seemed to be OK so I began to put it back on. Figured out how the tensioner functioned and continued. However, once it was on, I realized that the pulley on the water pump was out of line with the other pullies. There was no way to tighten it so back to Gordon Marine in Gan on one engine, luckily the one with power steering. Technician there was vey helpful, knew exactly the problem. Apparently this is very common with this engine. Luckily I have the extended warranty so all costs are covered. He was able to get one in overnight and I saw the courier arrive at 6:45 this morning with it. The only downside was that they could not get it installed until Monday so we're here in Gan for 3 days. Had a front row seat for the poker run and we're enjoying the town. Hopefully we'll be back on our way Monday afternoon. The tech mentioned that next time, in 3 years or so, and near the end of our warranty, to get an aftermarket water pump that it designed to not do this. I'm not sure the details but am disappointed these engines are susceptible to this malfunction. In the end, we changed our trip plans and are still on the water enjoying the boat!

kneedeep

Sorry to hear about delay, but at least it's covered. How many hours on the engines when the pumps went? As you know, I have the same boat with the same engines so I'm a little nervous. I have about 170 hours & haven't had any pump problems yet. I did change the impellers this year.

Black_Diamond

Sounds more like an install problem to me. Otherwise how did he fix it and say it's good for 3 years?

OldDogNewTrix

We had 330 hours at the end of last season when the starboard pump was replaced. We bought this boat new in June of 2010 after it sat on the dealers lot for 10 months. Other than this, it's been a great boat! i'm only concerned because it certainly seems more of a design problem than normal maintenance wear and tear. We now have 385 hours when the port one went. The tech was talking from experience with this specific engine and water pump. If we continue to boat like we do, we should be looking at a repeat problem in 3 years, a year before our warranty is up. We had the impellers replaced last winter, every 3 years. That was when they noticed the starboard water pump was in need of replacement. At least we're covered 100%!

212rowboat

There is a nylon type bushing on the main shaft of most wp's.. it soils the sheets, and the shaft will slip forward and backward, breaking the seal and spitting water (or coolant).. its what happens to pumps most often when they fail.. that same play allows the pulley to malign.

And, you want this to happen...

The alternative is a pump with worn blades that doesn't move neither the volume or the pressure needed to consistently cool and engine.. when the blades wear, it makes enough wiggle to unseat that bushing and spray your hold.. announcing, basically, that its time for a new pump..

I've seen engines overheat w/o obvious reason... Everything in the world done to try to figure it out, and finally pulling the pump just to find pencil thin spinners, stubborn bushings and weep passages, and because the design (which is maybe by design, maybe not, and another conversation either way) didn't perform like it should announcing its imminent failure.

Edit: my phone is funny.. it changed mis-aligned to malign.. I'm not certain the two could logically be used in the stead of the other in any circumstance.. :-)

OldDogNewTrix

Thanks for that explanation drew actual, makes a lot of sense. It got changed out and we're back out on our way. This mechanic mentioned that for some reason he sees a lot of breakdowns from factory built boats however once they're replaced individually like ours was this morning, they hold up much longer, we'll see. We got 330 hours out of the starboard one and 385 hours out of the port one.

OldDogNewTrix

Al, these were the raw water pumps. The replacements have been fine so far. Both were originals that broke down. And I watched the mechanic install the pulley with that special tool. From what I thought he told me, the rear portion on the originals were cast whereas the new one is plastic witha stainless steel plate,does that make sense?

Rocketman

I have volvo engines with 180 hours. Lost my starboard pump last year and port this year. For me they started leaking and J was told they couldn't be rebuilt.

OldDogNewTrix

Thanks Al, that explains a lot. Water levels were down a lot last year and probably contributed to the short life of both pumps. I now have the new ones with composite plate and stainless liner. Hopefully I'll have better luck with them.

Lifes Good

VP Water pumps can be rebuilt.  VP just wants to sell you new ones for $400.  A rebuilt is under $20.  All you need is a new bearing and truck shops have them.  The other part is called a sealing ring that VP still sells.  I have one spare pump and I rebuild as I need to.

I have part numbers if needed.

Rocketman

Life's good please post parts. Just replaced my pump on port engine and starboard was last year. My mechanic said they couldn't be rebuilt.

Lifes Good

Hope you still have your old pumps. here are the part numbers for the vp sealing ring and after market bearing. if you cant get the bearing in your neck of the woods try this place were I get mine.

Lifes Good

you will need a bearing press to pull the bearing and a rubber mallet to tap the new one back in. pay attention to how the old sealing ring comes out to set the new one properly. do not over tighten the 4 outer brass screws and be sure the o ring is clean and set properly. the o ring comes with a new impellar.