Boat cooling system

MAL44

Newbie
Aug 8, 2006
96
21
8
58
Rancho
Name
Mark
Boat
Proline 170
How long should I wait for water to start pumping? I have a 1995 mercury/ force, force mercury and when I started it no water pumped for about 1 minute then only a trickle after about 2 minutes. The temp gauge didn't move and the engine was not hot to touch, I'm used to my stern drive that pumped good water after a minute, any advice?
 
Last edited:

Done_Deal

Member
Sep 10, 2004
564
240
43
Santa Monica
mysite.verizon.net
Name
Joe
Boat
19' Home Built
How long should I wait for water to start pumping? I have a 1995 mercury/ force, force mercury and when I started it no water pumped for about 1 minute then only a trickle after about 2 minutes. The temp gauge didn't move and the engine was not hot to touch, I'm used to my stern drive that pumped good water after a minute, any advice?
Your water pump is shot. Do not run the engine until you replace it.
 

gved823

Member
Sep 12, 2009
494
239
43
Lakewood
Name
Gary
Boat
Sold
Had a 99 120 force, check t stat & if tubing outlet is clogged. Top 2 cylinders run hotter, that is where most failures occur. They get hot and head gasket fails. Run mix at 40 to 1, keep rpm' s below 4000, clean plugs before every trip and carry spares. This will prolong life. And lastly, replace impeller , $10. Good luck
 

MAL44

Newbie
Aug 8, 2006
96
21
8
58
Rancho
Name
Mark
Boat
Proline 170
Thanks for the reply, I put the boat in a tub of water and it seems to pump good now, I read somewhere that when on the cups it will suck air and water and I'm sure that's what was happening, the engine still trickles at idle but pumps good at higher rpms, thanks again for the advice
 

Stomper

Clatu Verada Fishon
Oct 2, 2009
148
31
28
Humboldt Bay, Ca.
pages.suddenlink.net
Name
Robert Reed
Boat
15 foot pilothouse trihull with radar and other electronics from hell
Yea, they always pump better when the LU is submerged rather than on muffs. Having said that, I had a pumping issue that was caused by the pump tube from the LU to the power head losing it's seal on the lower unit. That can be inspected when you change the impeller because usually both require that the lower unit be removed. The other items mentioned above should also be checked.