1981 Mercury 9.8 outboard cooling
 

Looking for advice...... The outboard ate which was probably the original
Impeller. It overheated and did the loss of power and stall routine.
After taking it apart, I found the guide tube had melted and there were bits
of impeller stuck in the tubes. I removed the powerhead, blew out all the
passages, replaced the base gasket. Pulled off the exhaust plate and checked
for debris. Removed the head water jacket cover and checked for debris.
I replaced the guide tube and the impeller with the correct size.
Here is what happens... I am getting intermittent water out of the tell
tale.The exhaust cover is sometimes hot and sometimes cold. This is with and
without a thermostat.
I believe I should have a solid stream out of the tell tale. I get exhaust
or a weak dribble. when I run it in gear fast I get an intermittant stream .
but not real strong.
I have had the powerhead off about 4 times checking and went as far as
putting a drill on the driveshaft and putting the tower in water and
watching water coming out of the tube.It came out as a stream but I don't
know how strong it should have been.
The small fiber grommet on top of the water tube is good. All passages on
the block are blown out and not plugged. Maybe the plastic nylon water pump
cartridge is warped from the overheating.
I guess my next step is to replace the waterpump cartridge. Any Merc guys
please advise. Thanks in advance , Matt.