mercury 7.5 thunderbolt water pump question

i recently purchased a 7.5 hp mercury outboard and i have noticed when i start the motor it takes about 10-15 seconds befor water starts to flow from the pee hole and when it does it is very hot, and it stays hot , ive been running it in a bucket , so i tend to get some sputter in the flow i am assuming this is from the exaust bubling up inside the bucket and geting sucked up through the water pump, i guess my question is how long is normal before water statrs to flow out the pee hole and how hot is it suposed to be.

Re: mercury 7.5 thunderbolt water pump question

sledge said:

i recently purchased a 7.5 hp mercury outboard and i have noticed when i start the motor it takes about 10-15 seconds befor water starts to flow from the pee hole and when it does it is very hot, and it stays hot , ive been running it in a bucket , so i tend to get some sputter in the flow i am assuming this is from the exaust bubling up inside the bucket and geting sucked up through the water pump, i guess my question is how long is normal before water statrs to flow out the pee hole and how hot is it suposed to be.

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my 75 merc 650, although a little diferent in size, starts flowing pretty strong alomost immediatly, and even after running hard for 20 minutes it doesn't get very warm...

Re: mercury 7.5 thunderbolt water pump question

Change the impeller before your motor burns up! Water coming out of the telltale should be a steady stream, bubbles and warmth indicate inadequate flow and first thing is to replace the impeller.

With the lower unit off, check for other circulation problems by blowing air up the water tube or hooking up a water supply to the tube to see how well water flows thru the powerhead.

BTW if the telltale gets plugged or partially blocked, the best way to clear it out is with an air nozzle up the tube.

Real cheap for impeller or kit at www.boatfix.com

Cheers.............ed

Re: mercury 7.5 thunderbolt water pump question

i think i figured out the problem , i ran my preasure washer through it the large tip or "soap tip" lowest preasure it has from the top trough the ruber hose forcing water through it in reverse and out around the prop and had a bit of junk come out , runs fine now i can actualy hold my hand under the strem at idle now i guess there was some blockage keeping the water from circulating properly or restricting the flow. i went back to the place i purchased it from turns out it was the owners motor and it had just had a new entire water pump kit put in about three weeks before i bought it so i guess i must have sucked some junk into it first time i had it out, if thats the case then it doesnt take much to clog this thing up any suggestions on how to minimize that problem, the intake is on the underside of the fin over the prop with a small round vent,unlike many others that have them on the sides of the lower unit.

Re: mercury 7.5 thunderbolt water pump question

have you removed lower lef from yr 7.5,i cant get mine off and ive undone 6 x nuts at top and 2 down below-HELP pls?