Water tube seal between powerhead?

[jason32038]

Is there a seal that I dont know about or can't find that goes between the water tube and powerhead? The piece that holds the water tube looks kind of IFFY like there should be some type of seal there and I won't trust it to seal once I get my powerhead done and back on the boat.

 

[pnwboat]

Re: Water tube seal between powerhead?

What motor are you working with? Most of the 4 and 3 cylinder motors have a seal at the top of the water tube. See items 3 and 4 in the diagram.

http://www.boats.net/parts/search/Merc2/Force/125%20H.P.%20%281989%29/1258F9B/GEAR%20HOUSING/parts.html

 

[Frank Acampora]

Re: Water tube seal between powerhead?

If you are asking about a 3 or 4 cylinder engine, the rubber grommet that holds the water tube into the top mount inside the midleg seals against a boss on the bottom of the match plate.

The rubber does get hard with age and I too, do not trust this seal. When I remove a powerhead I will usually add on top an appropriately sized O ring or at least add some silicone RTV before replacing the matchplate onto the midleg.

I have toyed with the idea of extending the brass water tube a bit so it enters the hole in the boss but this has drawbacks.

If you are truly concerned, add a pressure gauge on the block's water passages and/or a "pisser.".