Water Passage Deflectors and Thermostat - 25hp Johnson

When replacing the head gasket on my 1979 Johnson 25, I came across these 3 rubber
tubes called Water Passage Deflectors. They were crumbly from an overheat by the P.O.
Using a few odd tools, I managed to get them out and clean the water jacket thoroughly.
New ones will be here next week with the head gaskets.
Now, I am assuming to put the new ones right back as the Service Manual suggests ???
Any Permatex required ? Or, just push them in and and get them straight.

Also, the Thermostat was removed by the P.O. - - - probably the reason for the overheat.
I am in Central FLorida, the coldest water I will be running in will be 72*
so is a Thermostat really necessary in warm fresh waters ????

Yes - a thermostat allows the engine to heat up to operating temperature, not the other way around.

The thermostat warms the engine at idle and low speeds. This creates the best idle possible and also reduces the possibility of condensation forming in your engine while running.
Once up on plane the major volume of water by passes the thermostat and cools the engine.
I normally use gasket sealing compound as a lubricant to install the deflectors....and needle nosed pliers.
Bet if you check those water temps you will have much less than 72 right now.....we are in the high 50 temps in the lakes just North of you. Fishing has been slow as a result.
BTW - there is an Antique Outboard event on Lake Alfred next weekend if interested. Will be a one day event on the 22nd.

Thanks for all the info guys !!!
Just to reiterate - - - This motor was running "okay" off and on for the past few years ....
I just had so much going on that I could not devote even a full day of boating until now.
and now, I am finding all these GREMLINS that need to be dealt with.
water in the gas, leaking fuel hoses, yada yada yada ... and now leaking head gaskets.
After doing a lot of more reading on the functions of the outboard thermostat, I will put a new one in.
The head and water jacket cover sanded down smooth on Wet-r-Dry sandpaper on a plate glass.
so the new gaskets will make a very tight seal -

As for the Deflectors, I figured it out - once I got the old ones out and cleaned up the jacket goo...
it is clearly marked where they go, just slide them in.
The P.O. really did a number on the powerhead .... it got so hot that it melted the magnetos, turned
the white paint to a light grey, melted the Water Deflector Tubes and the rubber coating on the
wire holder clips are melted too.
Getting it all cleaned up, it looks really good. Nice cylinders on the inside with NO scratches or burned
issues. So LUCKILY, it will be running like an old Foot Treadle Singer before next weekend.

Thanks for the heads up on the Lake Alfred gig ... will try to make it.
March 28-30 is the Antique WOOD Boat Show in Mt. Dora (Lake Dora) .....
just makes you drool over all that mahogany!!

[url=https://www.tinboats.net/forum/viewtopic.php?p=344299#p344299 said:

Barefoot_Johnny » Today, 12:47[/url]"]
Thanks for the heads up on the Lake Alfred gig ... will try to make it.
March 28-30 is the Antique WOOD Boat Show in Mt. Dora (Lake Dora) .....
just makes you drool over all that mahogany!!

Click to expand...

Actually, that show is now in downtown Tavares. Hasn't been in Mt. Dora for several years. Better docks and bigger green areas for display plus restaurants right across the street from the venue.

oh wow, thanks Pap !!
I would have driven all the way to Mt.Dora for nothing.
My brother now lives right there in Tavares, not far from the Rhino Propane plant.
(He got tired of the Virginia ICE STORMS) Lives on a canal with a new 24' pontoon.
Thanks for the update !!
Johnny