? 165 Mercruiser Overheating

[mi19ch]

I have a 1986 Galaxy bowrider with a 165 mercruiser with the lay up cooling system. The gauge is reading 200 within like 5-10 mins hooked to to the water hose. When we take out it says its runing 240 but the boat runs great. I have replaced the impeller, thermostat, temp. gauge. I replaced the sending unit once before thinking that was the problem but it was still reading hot but when I changed the thermostat I broke that sending unit so I but the old one back in. I have did every thing I can think of wondering if any one could help. Its not getting water in the oil so I didnt think it was the head. Thanks

 

[Bondo]

Re: ? 165 Mercruiser Overheating

The gauge is reading 200 within like 5-10 mins hooked to to the water hose. When we take out it says its runing 240 but the boat runs great.

Ayuh,... Try another Gauge,... A Mechanical 1....

I Doubt you're running 240? without blowing coolant out of the system.....

 

[TheSeasLife]

Re: ? 165 Mercruiser Overheating

I would really take a look at everything again. Today was the worst for family boat. We have a mercruiser 190 and it was running perfect for days. Check all fluids before going out everytime. Thermo gauge was reading between 200 and 220 for days but when I checked everything it was perfect. Motor ran so smooth and quite. Well here the bottom line: Like I said look over again. Blew a head gasket. Boating over for awhile now. Good Luck

 

[rockyman]

Re: ? 165 Mercruiser Overheating

what you may want to replace is the water pump in the motor, from what you are saying it sounds like a water pump issue .

 

[mi19ch]

Re: ? 165 Mercruiser Overheating

Yeah I check all fluids before going out and while im out and motor is cool ill check again. I changed the water pump in the foot im not sure if mine has a water pump in the motor its self due to it haveing that lay up cooling system.

 

[mi19ch]

Re: ? 165 Mercruiser Overheating

Some pices of the impeller were missing would that be a problem? Where would they go and how could get them out?

 

[cr2k]

Re: ? 165 Mercruiser Overheating

BINGO...You MUST find ALL the pieces. If you have power steering it is most likely in the heat exchanger. Follow the raw water line in to the boat and check the first thing it hooks to, and so on, until you find all the pieces.

 

[mi19ch]

Re: ? 165 Mercruiser Overheating

Will do thanks mine doesnt have power steering but I will check erverything out.