Replaced impeler, thermostat. Cleaned sea strainer. Still overheating. what next?

are u getting water pressure at speed? In my situation, my transom plate hose fitting insert was corroded and was restricting flow-opening should have been about 15 mm, was corroded to less than 2mm-fair flow at idle (spitting out exhaust pipes) but at speed- melted manifolds.

Good luck

Hard to tell without knowing make,year, size what drives ect. Check water flow to thermostat housing. Could be manifolds and risers, how old are they?

Check inlet side of oil cooler for pieces of the old impeller

Thanks for the replies, i had no access to a computer for the last week so i'll catch you up to speed. My boat is a 95 powerplay 33 sport deck. Hp500's bravo's. It has the transom water pick up with sea strainers. While floating in the lake i pulled the covers off the strainers and plenty of water comes up flooding the bildge. The boat also overheats while running on the hose. I replaced the impeller but it was intact and looked ok. I replaced the thermostat also. Boat ran good for 20 min or so then temp gauge went up to 260. Seems to be an intermittent problem. I think my next move is to flush out the oil cooler. I have gotten quite a bit of sand in my strainers from beaching the boat and its possible the oil cooler may have some small stones in it. Would the oil cooler being plugged cause my motor to overheat?

When an impellor shreds the pieces go to the oil or powersteering or fuel cooler if you have one, whichever is first, all the water has to go through the coolers, so it's possible that the pieces are blocking the inlet water side.

If your motor got hot, it's a good idea to replace the t-stat also.

Wobble, I replaced the impeller and thermostat and this did not fix my problem. The impeller was intact when i took it out so no pieces floating around. I have had the strainers full of sand a few times so im guessing that could be blocking the oil cooler. Thanks for the reply.

when you replaced the impellers where the housings scored ??????

if you are filling the strainers with sand i'd try and pull the block drain plugs and see if the block is full of sand.....you may not be getting full cooling capacity......but my first thought was to tell you to back flush your coolers etc....

They seemed ok, i rubbed the inside down with vasoline to make the impeller slide in easier.