Low output water pump on 30 hp Chrysler

[fucawi]

Am having problems getting a good water flow through my 78 30 hp . the pump does not seem able to overcome the exhaust pressue and the tell tail (pisser) fitted to the top of the engine has no output......presently have the pump on the gearbox in a bucket and am driiving it with a drill ...all the pump is under water and has new 10 blade impeller ..I am told by my marine supplier this is an upgrade on the 6 blade. a good 6 blade gives similar results. The pin is in place driving the impeller and the shaft seal is good.
Output is not high ..you could **** almost as fast ....any ideas how to judge the output or anything stupid I have missed ....
Thanks in advance

 

[Nordin]

Re: Low output water pump on 30 hp Chrysler

How is the surface of the pumphousing. The wall, is it pited, small grows?The lower steelplate, the went hole in the housing free?

 

[fucawi]

Re: Low output water pump on 30 hp Chrysler

vent hole and stainless plate are good ..casing is smooth .......

 

[jerryjerry05]

Re: Low output water pump on 30 hp Chrysler

Sometimes the pickup tube will wear down or just not fit right.Allowing the water to go everywhere but up the tube.Couple of days ago someone had trouble with an older motor and added a piece of hose to the end and it sealed it enough to make it work.
The tube is cleaned out.Old bits of the impeller not clogging it.
Does it work when the lower is off?Hook a hose and start it with the lower off.Maybe remove the thermo housing as you do that and see if it's getting that far.
Good luck.

 

[fucawi]

Re: Low output water pump on 30 hp Chrysler

tube solid in the head (not loose) pipe clear .blown with compressed air ..no water at T stat ..pump is in a bucket with a length of pipe in the outlet ..."squirts " out about 3 inches