overheating merc 9.8, exhaust in cooling water

parrisw

Ensign
Joined
Jun 8, 2009
Messages
985
I just replaced an impeller on a merc 9.8 cause no water pumping, the old impeller was way bad, put it all together and it still wont pump?? There seems to be exhaust coming out of the pee hole. And when you take the hose off the pee hole and blow into it it comes out of the exhaust through the prop. I then poured water in the hose backwards, expecting it to come out of the pipe that goes into the water pump, and it didn't instead it comes out of somewhere in the upper housing if you look up through the bottom?? Could something be rotted out????

Any help is much appreciated. Thanks
 

parrisw

Ensign
Joined
Jun 8, 2009
Messages
985
Re: overheating merc 9.8, exhaust in cooling water

Ok, I pulled the powerhead off, and didn't see anything wrong with it??? Why won't it pump water??? The tube that goes up to the motor looks ok?? The pickup tube looks ok as well? What to check?
 

green4themoney

Petty Officer 1st Class
Joined
Jul 21, 2004
Messages
318
Re: overheating merc 9.8, exhaust in cooling water

ok, lets start with did you set your impeller the right way by rotating the driveshaft CLOCKWISE?
did you remember to re-install the pump key? (that turns the impeller with the driveshaft)
now if you did those 2 things we have to start looking at some other possibilities

did you make sure you lined up the water pipe with the pump housing on re-assembly?

make sure your water tube seal is in good condition (this sits on top of the pump housing where the water tube gets sealed to the pump housing) and the passage from water intake to the pump is clear also make sure your water pump housing is free and clear of debris... heres a few simple tests you can run to make sure everything s ok, on the one where you run water up through the water tube, make sure that it fills the block then it should start coming down the driveshaft housing as well as out the telltale at the same time, if you run water up the block and it comes down right away and wont fill it up, im afraid your upper seal is gone

http://www.youtube.com/watch?v=gSWCV2mJz8Q
 

parrisw

Ensign
Joined
Jun 8, 2009
Messages
985
Re: overheating merc 9.8, exhaust in cooling water

ok, lets start with did you set your impeller the right way by rotating the driveshaft CLOCKWISE?
did you remember to re-install the pump key? (that turns the impeller with the driveshaft)
now if you did those 2 things we have to start looking at some other possibilities

did you make sure you lined up the water pipe with the pump housing on re-assembly?

make sure your water tube seal is in good condition (this sits on top of the pump housing where the water tube gets sealed to the pump housing) and the passage from water intake to the pump is clear also make sure your water pump housing is free and clear of debris... heres a few simple tests you can run to make sure everything s ok, on the one where you run water up through the water tube, make sure that it fills the block then it should start coming down the driveshaft housing as well as out the telltale at the same time, if you run water up the block and it comes down right away and wont fill it up, im afraid your upper seal is gone

http://www.youtube.com/watch?v=gSWCV2mJz8Q

Thanks for the reply. I guess I didn't pay attention to this when I put it on, turns out there was no pump key when I took it apart, my boss, who's motor it is, says it hasn't worked properly for a long time, so someone's been in there before. So I took it all apart again, made my own key for now, put it together again, not it pumps good, but now it doesn't run right, it wont stay running GRRRRR, if it's not one thing its another, I'm thinking from turning the motor upside down a few times maybe screwed up the needle and seat???? Who knows, so off comes the carb again.
 

green4themoney

Petty Officer 1st Class
Joined
Jul 21, 2004
Messages
318
Re: overheating merc 9.8, exhaust in cooling water

make sure your carb is clean and you adjusted your low speed needle accordingly, you screw it in gently untill it seats and then back out 1 to 1 and a half turns, if its running ok just not for very long then it probably needs a fuel pump replacement
 

parrisw

Ensign
Joined
Jun 8, 2009
Messages
985
Re: overheating merc 9.8, exhaust in cooling water

make sure your carb is clean and you adjusted your low speed needle accordingly, you screw it in gently untill it seats and then back out 1 to 1 and a half turns, if its running ok just not for very long then it probably needs a fuel pump replacement

I was thinking the fuel pump as well, but the day before it would run fine? It never kept dying?
 

green4themoney

Petty Officer 1st Class
Joined
Jul 21, 2004
Messages
318
Re: overheating merc 9.8, exhaust in cooling water

since it just stopped running randomly have you cleaned the carb or had it apart or anything?
 

parrisw

Ensign
Joined
Jun 8, 2009
Messages
985
Re: overheating merc 9.8, exhaust in cooling water

since it just stopped running randomly have you cleaned the carb or had it apart or anything?

Yes, I did all that before the water pump. It was flooding out, since it was sitting for a long time, the needle was stuck, so I took it all apart and cleaned it up, then all was fine, then had the water pump issue, so fixed that, now it's not running right??? Didn't get a chance to look at it today.
 
Joined
Nov 7, 2004
Messages
21
Re: overheating merc 9.8, exhaust in cooling water

does anyone have a digram of how to take the hole bottom end apart to get to copper tube to replace it thanks
 
Top