lately my 1990 evinrude has been overheating a lot lately with my siren going off and it won't run pass 3000 rpm unless i let it cool down for half an hour. it seems to be pumping water fine. this did not start happening until i used it for tubing one day with friends. do i need to replace the water pump? the impeller? any advice would help.

If it takes that long to shut off the alarm when it overheats, someting is definately letting things get too hot and better fix that before damage occurs. I'd say water pump/impeller is a good first step although it can be alot of things. I only say that because my merc 50hp has a similar issue but only when I go over 4500rpms.

I'd say water pump first and if that doesn't fix it, check thermostat. Also I recommend you get a compression tester and check cylinders. Very easy to do and the tester is only 30 bucks at auto store. Get the one with a flex hose and dual adapter which makes it very easy to use.

You had better have the entire pump replaced unless you know when the last time it had a housing and base plate. I always put new baseplates in regardless just to elimitate any liability.

But, if it got that hot. first thing you need to do is check the compression.

Hope everything is ok.

yup, compression test will tell if you damaged it by running overtemp.

thanks for the replies. i will get my outboard checked out.

Also check your thermostats. If they are not working proerly then they will restrict water flow through the engine.

yup got to b the water pump

guess what...... now i just fried my starter on saturday before a tourney!! i got impatient trying to start my boat and i turned that switch on that goes to the trolling batteries. i pumped 24 volts to my starter and now it just clicks.

The solenoid will click not the starter, you probably got it. Try bypassing the solenoid to check. Best to replace all cooling system components when in doubt. Hope you did`nt damage the power-head. GOOD LUCK