does anyone have any idea if a 1999 tracker series merc 25hp 2 stroke has a thermostat. should i have a continuous flow of water all the time or just when i give it some gas. at idle i get spitting water but not a continuous stream until i give it the throttle.  if your not sure any idea where to look to see if i have a t-stat

Not sure if it has a t-stat or not; I can tell you that on my '03, it spits out the same amount of water regardless of rpm.  I think it's time for an impeller.

-J

I agree,

You should replace the water pump impeller once every three or four years, but if you run in shallow water (trenching)  ;D   ;D

maybe more often.  

I've cut a few trenches my self. Thank God for SS props!!  

how hard is it to change the impeller? where is it located?

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how hard is it to change the impeller? where is it located?

I don't think it's too hard to change out once you've done it a couple times.

You have to remove the prop and drop the lower unit to get to the impeller.  Keep in mind that while you're there you will probably want to replace the seals too.

S