ZR6 OVER HEATING, SUCKED UP SAND

[guyhawk]

I would really appreciate some help with this, to cut a long story short my 2 year old son drove daddy's pride and joy up the beach filling the water intake pipe and strainer with sand which i did'nt notice until the over heat alarm went off so i emptyed the strainer of sand, ran the engine for a few seconds then emptyed it again (did this several times until clear) but ever time i use the boat the alarm goes off after approx 10 mins or so at 24mph with it going off sooner the faster i go then if i slow down to idle the engine cools down to about 155f (alarm sounds at 198f). I have changed the impellor even though the old one looked o.k, I have taken each end of the heat exchanger off and this seems clear and have taken the drain bolt out of each exhaust manifold where i did find a small amount of rust and sandy much but only about half an egg cups worth and its still over heating does any one have any ideas, could it be the thermostate even though its closed cooled, could over heating cause damage to stat, oil/water levels are fine and clean and the rubber seal is still in the strainer so i don't thinck its sucking in air, its a 2008 zr6 in a 220 and my dealer is over 250 miles away so would really like to sort this out myself as i think it most be a blockage some where. i have also pulled most of the pipes off and have checked the in line oil cooler, any suggestions would be great, Thanks

[NAWTEAK]

RE: ZR6 OVER HEATING, SUCKED UP SAND

There is a white plastic valve just after the pick-up where the flush is connected. If sand gets in there it will clog it up. Take it off and clean it out so that the spring loaded inner is fully functional.

good luck

[guyhawk]

RE: ZR6 OVER HEATING, SUCKED UP SAND

Nawteak was spot on, small amount of sand had caused it to stick closed. thanks nawteak

[Joesboatn]

I had the exact same problem with that same valve on my 01 SAN. I canned it and put in two threaded brass fittings that im able to disconnect and hook up my garden hose so I can run my engine in my driveway. It seems like that valve restricts water to the cooling system and or you have problems just like you did.