Overheat at idle 95 SS GT40

[chefred112]

Hey guys, I've searched high an low for an answer and tried a bunch of stuff, mostly making sure strainer gasket was there an was tight and checked to make sure hose connections were solid.... with those symptoms mentioned in title, here is what I did a test on...removed strainer assy, I blew into raw water hose and saw bubbles come out the water outside the boat, sucked in pretty easily water thru that same hose and spit out...then I poured water into other hose that goes to tranny cooler and impeller housing and filled to top, then bumped motor to see if the water would suck in...but just the opposite happened, dirty water came gushing out. Is this what is supposed to happen?

[t.franscioni]

Not sure I fully understand what your describing you did as a test. Sounds like your concerned that your water pump is pushing water out of the intake pickup instead of sucking water in?

if so did you recently pull your raw water pump off for service? They are directional so if they are installed upside down they will push water instead of suck water.

[BigBen_UK]

And if you've not serviced the pump, you need to replace the impeller + wear plate (Minor Repair Kit: 23979). The screw that holds the cam in should face the engine - i.e. the dome screw you can see on the top in the pic here http://www.sherwoodpumps.com/en-us/P...Literature.htm

[chefred112]

As I was on a houseboat trip I thought I replied on my mobile fun....But HUGE thanks for the suggestions!!! I indeed did replace the raw water pump assy that came with a new impeller and did install it 180 degrees wrong! Luckily, I did keep the old assy (with 10 minute old impeller) in the boat and installed that 180 degrees with the screw facing inwards! I was super thrilled to be able to use the boat during the evening Saturday and all day Sunday... Thanks Franscioni for point me in the right direction and Big Ben for the confirmation and part number...man, joining this site has paid off bigtime..thanks again!!!

-fred

[BigBen_UK]

Yup, I've done that before on my 5.7 Mercruiser, so paid extra special attention to pump orientation and which direction to twist the impeller when doing it on my GT-40. Pleased your weekend was saved !