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Wierd Problem HELP

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alpha_ss

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Started up Merc 383 with Alpha ss drive and no water out of thru hull exhaust. Took hose off cooler and is pumping very little water. Pulled off lower gearcase and hooked up garden hose to copper water pipe in upper gearcase and lots of water out of exhaust tips. Check water passages in lower gearcase and are open. Removed impeller housing and impeller looked ok. Installed new seawater impeller kit and still won't pump water, Lower unit is in big tub of water because muffs will not work on a ss drive. Any ideas? I have installed probably 15 impeller kits over the past 25 years with no problems. Does the lower case need to be deeper in the water? Water is 2 inches below ventilation plate. Thanks
 
the water inlet holes need to be covered in water otherwise the pumps sucks air.

If the pump isn't working, it may be due to the impeller not turning....check the coupler to make sure it is spinning the outdrive's driveshaft (yoke).
 
Pull the pump base and make sure there is no debris that can clog the pump intake port.

Any chance you were sold the wrong Kit?

if that isn't it, only other option would be try another kit.
 
Haven't seen an SS in a while, but when it first came out Merc did make a special
earmuff-like part to fit over the torpedo intakes in the drive.
 
BT Doctur, You are correct. A Merc guy on another forum explained that the pump body itself must be under water to get primed. There is a small channel in the pump base that runs from the impeller to the area inside the case that primes the pump when the boat is in the water. Just the water intakes in water and the pump will not prime. I used the garden hose pushed against one intake to prime the pump and it started pumping. Learn something every day.
 
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