30HP EFI overheating

[MantukasZ]

Hi everyone,

i have Mercury 2009 30HP Efi 3-cyl 4stroke.

having problems with overheating.No water is coming into engine block, stops before the getting into engine itself.
After many tests and other replaced parts(impeller, thermostat, sensor and few others), i ended up removing engine head and changing upper water tube grommet in the oil pan section. When we opened It was completely clogged channels with minerals from salt water, grommet was cracked and water could get into the engine itselft - in general trash. All is fine now(i think), but we have found metal washer/plate (oem nr: 95275002) from the driveshaft housing.

We have tried to figure out where it suppose to sit, because it fell off on the floor after removing, so we couldn’t see where it was, but for sure it dropped after we got access to upper grommet. The only place i think it has to be on, is on top of that rubber grommet. If I understand correctly- you place that washer on top, and it squeezes the grommet down tight when re-installing the head and doesn not let for the rubber to expand into water channels and block the road for water to travel into an engine.

is that correct or not? Im attaching the pictures, and the part i am talking about is No: 24

Thank you for the help in front!

 

[Texasmark]

Just shooting from the hip here: The IPB is pretty explicit in the placement of the washer and I agree with what you said. I see nothing to warrant otherwise. Only questions here are 2:
1. Assume the 2 ports in the casting are for water inlet toward the rear and drive shaft toward the front.
2. Not sure which needs protecting, water port or driveshaft opening. I'd think examination of removed parts should show some sort of indentation on gaskets or corrosion difference on castings to determine which hole from which it came. Since water is coming in under pressure and drive shaft is just to keep ambient water out, it would go on the water channel.