Blown gasket on water impeller housing

[Bartman]

2019 250HP M/N 12500033A S/R 2B597338

I developed the overheating idle beep at 150 hours. Pulled the lower tonight and sure enough gasket is blown on impeller housing. Seems to be a common problem on these motors. My gasket was actually blown in two places. Not sure if the housing is flexing or if the housing lip is bottoming out and not getting enough "crush" to seal the gasket. Thoughts??

[krindgen]

I found this on my first impeller change, with very low hours on my 2S, a piece of that gasket was missing. Mechanic sent me pictures. Fortunately he found the missing piece and I wasn't experiencing overheat problems, yet.

[Matt Wayne]

I see this allot when changing the water pumps on any of the 3.0 lower units. I usually take a little bit of silicon and dab the gasket before putting a new one in. Not much, I just put a little bit on my finger and lightly wet the upper gasket and always use a new gasket. This seems to take care of the problem. I even see it in allot of fairly new engines where I know it’s the first water pump change.

[fishnfireman]

which lower unit..

[SilverFox579]

Don has said this is same pump as used in the Opti and he recommends the same maintenance schedule, annually or 100hrs whichever comes first, despite what the owners manual says.

[06 SB]

8583DC15-1216-4BEC-A068-56C55EA7DDEF.jpeg

This was mine after 22 hours of all clean water. The back end blew out. It was an easy fix but surprised that it happened so quickly. I have another 15 hours on the new gasket set and impeller with no issues so far.

[TritonTRXV8]

Thats interesting i have never experienced that. Possibly be from a warped housing?

[JAZII]

Eee to use the metal bushing/gasket supplied with the rebuild kit

[EuropeanAM]

Eee to use the metal bushing/gasket supplied with the rebuild kit

Not quite sure what you are referring to on that one.

We do sometimes see this- often when there has been a sudden change in water SUPPLY to the gearcase (such as occurs when gearcase bounces out and back in the water).

That being said... properly reassembling the water pump with new gaskets and proper torque on the retaining bolts (NO additional sealant on upper gasket) usually resolves the problem.

[Hart1]

My 2023 Pro XS 200 blew out the impeller gasket with 3.9 hours on it. I got the overheat beep and the engine went into guardian mode. My mechanic said the impeller housing bolts were not tightened down properly from the factory. He said it is not uncommon.

[Triton03Vance]

Rubber coated wearplate from Pro Marine parts (part #27997) and you will never have a blown out gasket again. My paper gasket has blown out twice and both times proper installation and torque was done. I have been running the rubber coated plate for 6 months now and no more problems. Wearplate is rubber coated on top and bottom so that takes the place of the upper paper gasket and the lower thin metal gasket that is normally used..you can also apply aviation sealant to the bottom side of the OEM paper gasket and helps also to prevent blowouts or just get the rubber coated plate and not mess with all of that..the choice is yours..

[Redngoo]

I run a mercury rubber coated plate gasket. Mine is not a 4stroke and is a standard lower unit. Do not rember who give me the mercury part # but it work and is cheap. In 8 yrs I have never seen it blown out. I generally change the rubber plated gasket every other time I change waterpumps(yearly)

[Another Distraction]

That $18 pro marine plate looks like it'll help resolve the issue. I'll order one asap and look it over.

[Triton03Vance]

That $18 pro marine plate looks like it'll help resolve the issue. I'll order one asap and look it over.

I have no doubt that when you see it in person and look it over, you will like it and it will not blow out. I was impressed when i seen it in person, my first thoughts when holding it in my hands was there is no possible way this can blow out.

[EuropeanAM]

I would definitely NOT recommend attempting to use aftermarket or incorrect components here, especially on an engine that is still covered under a GOLD Product Protection Plan. Doing so could potentially cause for difficulties as any modification of the product is grounds for denial.

The OEM gasket will work fine if you will simply apply Perfect Seal (Aviation Gasket Sealer) to the bottom of the impeller gasket, and torque the screws to the appropriate torque.

If this is the first time the impeller has been replaced on this engine, it's way-overdue. Was due for replacement on or before 3/01/2022 (along with other 3 year/ 300hr maintenance items).