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MOP
08-17-2005, 11:43 PM
The run before this one I found maybe a gallon or two of salt water in my bilge, carefully checked every inch of the raw water circuit, checked tightness on every clamp found nothing. Again tonight pulled the plug and water again! I know the bilge was dry after a few sub 60 runs, I was in the motor hole checking out my speed problem tonight. So it was after going over 60 that the water came in. I looked things over and found my sea water strainer wet but the cover was nice and tight and the gasket was fine, I am pretty sure the dual pickups on the new drive create too much pressure in the system at speed and force water out of the stem of the strainer. Now to get rid of some of the extra water, thought about blocking the lower pickup holes but may opt for something else. Thinking about tapping off the inlet line with a check valve after the strainer and shoot the excess at the heat sink on the top of the drive beats a bolt on shower.

Phil

MOP
08-18-2005, 07:52 AM
MP I am thinking of trying a ½" dump above the drive with a non loaded check valve mounted vertically that would open as the drive pressure rises, the new drive has a big finned heat sink on top it does not get near as warm as the BH did with the flat top. I need to fool around with some ideas I have on a discharge nozzle to get most of what comes out to hits the drive. I have not installed any type of flush adaptor, I take the cap off the strainer check for debris and stick the hose in the top works very well. I thought about tapping off the pump which is the old bronze one but that would do little to relieve the pressure at the strainer. I still may opt to plug the lower pickups, being close to the bottom in shallow water they must suck up more junk.

Phil

MOP
08-18-2005, 07:40 PM
First I need to relieve the pressure at the strainer, it is in line before the pump. My setup must have a check valve allow the overage to escape at high speed and to close at low speed or the pump will suck air through the shower tube. I picked up the stuff today to do the job total cost under $30 including hose and clamps, by chance have you priced the Merc unit I did whacko price for a reinforced plastic housing with a spring loaded relief valve. Mine is far simpler and basically fool proof, the only thing I need to make is the dump fitting. If the system pressure is still high I can always T in a relief valve from a point after the Sea pump and dump it through the same line. I found very high quality adjustable relief valves made of stainless and bronze for less then the Merc one, that is what I will use if needed.

Phil