Split Fuel Module - Mercruiser 5.0MPI

Update to the below; it's not the raw water pump, I was incorrect, it is the fuel module, right next to the seawater pump. The thing is split, front to back, along the side. The mechanic is still going to fix it, but I was looking online for the part, it appears to be a special order everywhere I look! I hope it's done before next weekend...

This last Fall, I had my mechanic winterize my engine, which is a 2007 Mercruiser 5.0MPI with the 3 point drain system. So, yesterday I spent half the day washing and waxing my boat to get it ready to put it in my wet slip. All is fine, back it in the water, start it up, but then I go and lift the engine hatch and notice water spewing out of the left side of the water pump. I shut the engine off and notice that they water pump housing is split all along the side from front to back. Apparently they never pulled the plug drains the water pump. I called the mechanic this morning and he is going to look at it and said he will fix it. My concern is, what else should I be concerned with in regards to other things that could be damaged? The main block appears to have been drained, looks like they only missed the water pump plug.

Re: Split water pump - Mercruiser 5.0MPI

Re: Split water pump - Mercruiser 5.0MPI

If that's all they missed, replacing it will fix the problem. But, pay close attention to your boats preformance when you get it back in the water. Run it hard, then check your oil for water. Keep an eye on your temp. Listen for any cylinders missing after the engine gets all warmed up. AND ASK THE MECHANIC TO CHECK FOR ANY OTHER DAMAGE THAT MAY HAVE OCCURED while he has it.

Re: Split water pump - Mercruiser 5.0MPI

Re: Split water pump - Mercruiser 5.0MPI

Yeah, I talked to him this morning and asked what else could be wrong; he said likely not anything, but they would check it all out before they "release" it.

Re: Split water pump - Mercruiser 5.0MPI

Re: Split water pump - Mercruiser 5.0MPI

Your mechanic sounds like an honorable guy. But you will still want to check out the things I mentioned. Because an engine behaves differently under load than it does on the hose.

Re: Split water pump - Mercruiser 5.0MPI

Re: Split water pump - Mercruiser 5.0MPI

I updated the thread as I ultimately had the wrong part, it is actually the cool fuel module, which is right next to the seawater pump. The starboard side of the casing is split. I'm wondering if a whole new module is required, or just the casing itself. Since I didn't cause the problem, I'm thinking a whole new module in case the freezing caused another problem. I've looked online and it appears that the whole module is a special order product.

Once they do replace it, I do want them to do a full inspection and when I put it in the water I'm going to give it my own shakedown and make sure all is well, as you said Havasuboatman....

Re: Split water pump - Mercruiser 5.0MPI

Re: Split water pump - Mercruiser 5.0MPI

I would venture to say that your problem started with the mechanics trusting these sorry drain systems Merc is using. You have no way of checking to see if each item is drained or not short of taking the drain system apart each winter.
If it were my engine, I would remove all of it and drain it the old fashoned way so you can check that each item is drained.
Those housings are available, just not something many dealers would stock. Since the housing itself is 400 bucks and the complete assembly over 800, don't expect them to replace the whole thing. If there is no water in the fuel side of it, everything inside should be fine.

Re: Split water pump - Mercruiser 5.0MPI

Re: Split water pump - Mercruiser 5.0MPI

Don S, I thought of you the first time saw this as part of their winterization process is to run anti-freeze through the system prior to draining it. Like you say "air doesn't freeze". From now on, when someone winterizes it, I'm going to follow them and pull the hoses to the engine and monifolds, etc. It's pretty easy to do/get to on mine.