Thermostat or not ..??

[fucawi]

Old question I guess but wanted to know what the gurus think ...in Noosa we always ran without the thermostat because parts of the river were shallow and sandy so the thermostat got blocked with sand and clearly the alarms came on . you could have a gallon of sand inside the water passages ....the old timers in the pub always said take it out ....never had any problem with fuel consumption etc I put a plate in with a 1/4 hole ...Both the engines I just bought had no themostat BUT this is the first thing to go when the engine overheats rather than checking the impeller...

 

[bentle]

Re: Thermostat or not ..??

Wow that much sand running through the impeller and pump housing would be like rubbing the rubber fins off with a piece of sandpaper as well as the fine inner metal lining the impeller spins against at high speeds. Personally the impeller is always the first check and fix, and then I work my way up from there.

 

[fucawi]

Re: Thermostat or not ..??

I had a 90 hp johnson block up with sand ....washed out a gallon of sand into a bucket ...backed up behind the thermostats ....towed in by coastguard from the middle of the biggest lake in the southern hemesphere

 

[bentle]

Re: Thermostat or not ..??

Oh man. that's not something you would expect to happen at all but I guess anything and everything is possible with a boat period. So I noticed you said you drilled a 1/4 hole in a steel plate and put it where exactly?

 

[fucawi]

Re: Thermostat or not ..??

instead of the thermostat ..held with spring

 

[bentle]

Re: Thermostat or not ..??

Oh I see. So how did that work out in the long run. I have to ask cause ya never know when it may come in handy. I would have thought to replace thermostat and away I go I hope.

 

[fucawi]

Re: Thermostat or not ..??

Well if you look at the area of the opening of the thermostat ..on small stats its only 1/16 on a 1/2 in dia circle so that equates to approx a 1/4 hole ....just wanted to keep the water flows in balance through the passage ways ...its equivalent to having the thermostat stuck open but without the restriction of the narrow pasage ...once you get sand behind the stat it closes and then the sand all backs up ....very shallow in the entrance to the Noosa Everglades ( australia) with sand bars and moving channels ...tricky...best tackled on the plane but shiiit happens

 

[bentle]

Re: Thermostat or not ..??

Ok that's very good advice and if I ever get stuck like that then I know I have some options. How does the impeller and housing hold out.

 

[fucawi]

Re: Thermostat or not ..??

well all the engines I had in australia had a proper pisser as the yanks call it so you could judge the condition by the strenght of the flow ...we always had the pisser pointed up like a jetski !!!!

 

[celtic gelf]

Re: Thermostat or not ..??

A 22 yr enigneer from Force.. Told me to run without a thermostat it will not hurt the enigine...Seeing how my overheated abit and reading that it can get clogged I'm going without...This guy is a life saver years of firsthand knowledge and hundreds of enigines for parts...

 

[scooper77515]

Re: Thermostat or not ..??

In a car, where the water is heated and recirculated, I would say NO since the thermostat slows the water flow down over the fins of the radiator allowing it to stay in contact with the aluminum or brass fins longer, to cool down.

But with a boat...it is fresh water all the time, so i see no reason for skipping the thermostat.

BUT!!! if you are sucking up enough sand to clog a thermostat, you HAVE to be messing stuff up elsewhere. Water pumps, impellers, etc.

Personally, I don't let my outdrive touch the sand at all.

 

[jimbo_jwc]

Re: Thermostat or not ..??

I've used the washer/ stainless for a restricter in a 120hp for 10yrs but when trolling after 20-25 min the buzzer temp alarm would sound and I put in neutral and rev up a little till it went off and continue . No ill effects and never replaced impeller . But did'nt know as much as now as my new 1987 mercruiser impeller scattered on driveway testing in drum . By the way this stopping and waiting taking out of gear is part of a trolling technique that is highly effective

 

[chrome dome]

Re: Thermostat or not ..??

ok, it's early.. l'm bored.. what is the largest lake in the Southern Hemisphere?

 

[jimbo_jwc]

Re: Thermostat or not ..??

After you tell everybody what vegemite is made out of ? We still love our Chrysler OB's

 

[chrome dome]

Re: Thermostat or not ..??

the main ingredient is yeast, a variety of which is also found in beer...

l'm not sure quite how to address your statement about Chrysler OB's other than to say we have a 120 hp ( and am watching a 70hp now ) though that is more of a love/hate thing LOL

simply trying to assertion which lake the OP is referring to, out of curiosity as well as wanting to stay as far away from the joint as possible

 

[chrome dome]

Re: Thermostat or not ..??

the main ingredient is yeast, a variety of which is also found in beer...

l'm not sure quite how to address your statement about Chrysler OB's other than to say we have a 120 hp ( and am watching a 70hp now ) though that is more of a love/hate thing LOL

simply trying to ASSERTION which lake the OP is referring to, out of curiosity as well as wanting to stay as far away from the joint as possible

as well as trying to ASCERTAIN it as well LOL

cartin' a bucket of sand around inside ya donk ( OB ) cain't be a good thing

 

[jimbo_jwc]

Re: Thermostat or not ..??

Lakes and rivers around here entice boaters to go way too shallow , hence my old mayhem boats impeller is the size of the housing and still working with washer restricter in place of therm. There is a time to be fine and a time its to crude to be true . Like Foster's coming in size of oil can .

 

[fucawi]

Re: Thermostat or not ..??

salt water lake that is Cooroibah

 

[jimbo_jwc]

Re: Thermostat or not ..??

While on a overnighter alone I needed more light in rear of boat so I found out that my propane lantern with large tank plastic bottom with molded small tank hole too fit right over my my 4.5hp johnsons gas cap tight enough to leave there allnight and it brought back memories of my first Chyrsler OB with the light on top of it. This motor taught me the trick of taking motor out of gear when trolling when dog gears kicked out . Paid to have replaced used a few times put it away without draining lower unit and seal wasen't replaced and water in bottom froze and pushed it out . Have thought of restoring and getting new seal and epoxying it in for retaining lip broke , Got to love all boating memories always learning something or eyes must be closed.