Thermostate or not?

[herndo]

About this same time last year I replaced my water-pump in my 89 Yamaha 90. I took my boat out yesterday and once underway I noticed that I didn't have a PEE-STREAM indication for water flow. I eventially got flow but it was very low pressure. I'm wondering if it's possibly a thermostate problem or the water-pump again? A buddy told me to remove the thermostat, he says you don't need it anyway. I'm going to check both. I live in Texas on the Gulf Coast.Do you need a thermostat in this area? And should't a Water Pump last more than a Year?

 

[edjr]

Re: Thermostate or not?

check your screens make sure you dont have junk in them restricting water intake i would would say pumps should last atleast 2 or 3 yrs min. but change every 2 as preventive maint.

 

[rodbolt]

Re: Thermostate or not?

depend<br /> if you ever started the motor with no water to the gearcase it can fry a new pump in 30 seconds. rendering a new pump a junk pump. the t-stat is also part of the water pressure control. tell your buddy he is an idiot and dont take anymore engine advice from him. tell tale on that motor is not thermostatically controled. <br /> I would suggest studying the flow diagram before attepting to reengineer the system.

 

[herndo]

Re: Thermostate or not?

Rodbolt,<br /><br />Thanks for your info. I had a feeling that the info my buddy had was not correct. To my knowledge I don't beleive I've started my engine without water. I'm going to double check my screens for any obstructions and go from there, and then go into the pump.<br /><br />Thanks for your much needed info on the thermostat issue.<br /><br />Herndo

 

[rodbolt]

Re: Thermostate or not?

also the the nipple on the exhaust cover likes to plug up. if the motor ran cool and did not overheat check the nipple, hose and the overboard restrictor for blockage.

 

[Silvertip]

Re: Thermostate or not?

Isn't it funny how neighbors always know more than engineers when it comes to designing outboards? If the engine didn't need a thermostat, it wouldn't have one from the factory. When it comes to engines, cooler is not always better.