Do i have a thermostat?

floatingwoody2006

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Hello again. trying to troubleshoot a 1976 blue stripe Merc 500 50 horse outboard. Im getting no water thru the telltale, but the passages are clear. I am planning on an impeller replacement, even though it was done last spring. Is there a thermostat in the mix somewhere as well? And i do not have the manual for this yet, but have it on order. Are these pretty simple to drop the lower on and get the Impeller installed in? I see the 2 bolts on the lower to start the process, but wanted to know if there's anything special in there, or possibly under the trim tab to look for.. Thanks.
 

Laddies

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Re: Do i have a thermostat?

No thermostat and yes there is a bolt under the trim tab
 

floatingwoody2006

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Re: Do i have a thermostat?

Thanks Laddies.So it's a sure thing i should see the pee hole almost immediately. Got my manual and removed the lower, and replaced a pretty good impellor. Discovered that the water tube guide was either missing, or fell off during removal, but im thinking it didn't get installed. I couldn't see it on the ground. SO..i have high hopes that that's what was preventing the flow out the relief. The seloc manual i got wasn't specific about a part # for it, and napa doesn't show that it fit's my 1976 merc 500, or even if it is supposed to be in there at all, but i think it is. If this doesn't work, im stumped.
 

Laddies

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Re: Do i have a thermostat?

Your engine doe not use a guide tube, while the unit is down hook a water hose to the engine supply tube to make sure something is not plugged up.
 

floatingwoody2006

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Re: Do i have a thermostat?

I guess im confused now..the copper tube coming down from the top to the water pump housing doesn't have any type of rubber gasket/o-ring on it, and the pump housing just seems like a hole that produces the water up the pipe. Neither have rubber o-rings or the like in them, nor do they have places that look like they should. The J/E impellers i have changed have at least had something to attempt to seal the 2 together. This seems like a strange design to me. I am absoluely sure there is no obstruction in the pipe, to the tell tale, and im sure the impeller is on the shaft key. Damn strange..:(
 

Laddies

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Re: Do i have a thermostat?

When you lift the housing there should be a rubber grommet in the housing held in place with a plastic one from the bottom up
 

floatingwoody2006

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Re: Do i have a thermostat?

I think that piece must be missing..You wouldnt have a part # or specific name for it would you?.. Thanks again man..
 

floatingwoody2006

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Feb 2, 2006
Messages
500
Re: Do i have a thermostat?

Issue solved. I can't believe how the simple stuff can really get the best of me. This motor will not for some reason operate correctly on Muffs, The way the relief tube is routed in the cowling with a bend to it, for some reason my garden hose was creating air bubbles in the bend, and not letting water flow. Didn't have a barrel to test with until this morning. Submerged sufficiently, and it started flowing nice. Well, The good news is i did get the manual, some merc lower unit knowledge, a new impeller, and some humble pie. Thanks again laddies..Very helpfull.
 
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