Water Clogged???

[snowstud98@hotmail.com]

I have a 75 mercury 50 HP 500, I can't figure this one out. I put a new impeller in it and still no water coming out the tell tale hole. There is steam and exhaust coming out of it.However when I spit water in the tell tale hole it comes out somewhere in the midsection,not the copper pipe or exhaust. Is this normal? I also tried running water up the copper pipe and it comes out everywhere but the tt hole. Is there a thermostat? any comments? suggestions? thanks

 

[Laddies]

Re: Water Clogged???

If the original impeller was broken up you probably have a piece of a blade logged in a water passage on a 500 it's usally the passage under the exhaust plate, between that area and the cyl. water jacket near the bottom of the water jacket. You can test by hooking a hose to the cooling tube to the powerhead, use moderate pressure and you should have water come out the telltale

 

[WillyBWright]

Re: Water Clogged???

The steam and exhaust are coming from the exhaust. It's being blown into the water pump. Check the housing and base. If there is any melted plastic anywhere, replace the whole pump. Check for grooves worn into the stainless cup and base plate. Replace if bad. There is no thermostat. With the gearcase off, blow compressed air into the telltale. Sometimes that backflushes an obstruction out the copper tube. If it ever overheated badly, a cracked block is a possibility. It almost would've had to lock-up as well for that to happen. There's a thick rubber gasket for the exhaust tube right behind the pump. Make sure that's there and in decent shape.