9.8hp?110model

If it does not have a tstat,would the water pump cause hot water to come out of the p-hole ?

If a motor is "overheating", that does not have a thermostat (many of the 15 horse and under Mercs never shipped from factory with a thermostat even if there was an allowance for one) could be caused by -

a bad waterpump impeller
a slipped impeller key
a bad waterpump gasket (base gasket or cover gasket)
a bad waterpump seal (driveshaft "oil" seal or water tube guide seal)
a hole in the water tube (salt can eventually corrode right through the tube)
a bad seal where the water tube meets the powerhead/exhaust plate
a blockage or build-up in the channels in the powerhead
a blockage or build-up in the water jackets which surround the cylinders
a blockage or build-up in the exhaust which is prevents the water from exiting
a bad powerhead base gasket which is allowing some water to bypass the channels

and I have probably missed a couple of other potential causes.

so best bet is to take to a shop.

They will probably charge you a bundle and rebuild the waterpump as there first step (which I would do coupled with a thorough flush of the whole system with a good dose of vinegar and water which dissolves all kinds of build-up).

If you even have some basic mechanical skills you can do a water pump yourself, with step by step help from a Seloc's manual for about half of what a shop will charge.

ok thanks i'll will try that first