94 Mercury 175/XRi Overheating

[esjr0969]

While running back to boat ramp, the overheat warning started to go off. The temp gauge was at the 3/4 mark. I noticed that at idle, there was no tell-tale, but while running at full throttle, there was a tell-tale. Boat ran fine that morning with no alarms. I haven't had the impeller replaced in a while, so my thought was to replace the impeller, thermostats, and maybe the poppet valve. So my questions are: 1) Should I have a tell-tale at all times? 2) Do you have any instructions on replacing the poppet valve?

Thanks for your help,
Eddie

 

[Chris1956]

Re: 94 Mercury 175/XRi Overheating

Eddie, A lot of those V6s have the telltale downstream of the thermostats. There is not telltale until the stats open.

it sounds like you are on the correct path. Impeller, Stats, poppit.

 

[j_martin]

Re: 94 Mercury 175/XRi Overheating

Eddie, A lot of those V6s have the telltale downstream of the thermostats. There is not telltale until the stats open.

it sounds like you are on the correct path. Impeller, Stats, poppit.

Just service the water pump. Replace all the worn parts, which will be the impeller, but may also be base plate, pump housing, gaskets and seals.

T stats usually won't fail unless plugged up or grossly overheated. Poppit is serviced if pressure is abnormal, otherwise leave it alone.

hope it helps
John

 

[esjr0969]

Re: 94 Mercury 175/XRi Overheating

Thanks for ya'lls input. I am going to try the impeller first and go from there.

 

[Zimzam]

Re: 94 Mercury 175/XRi Overheating

I have the exact same motor and had the same problem in May this year. I had the impeller changed and the themostats looked like they have been in there since the engine was new, so I had them chagned too. They also flushed the whole system to make sure I had no blockage. I also asked the question as why the water telltale don't start right away and they said on these Merc's the thermostats have to open first where other brands like Yamaha start flowing right away. Anyway after they got finish I went to the lake and had no problem with the overheating.