help impeller

[keplero]

I changed the impeller of row water pomp, for preventive maintenance.
The new one is Volvo original and looks exactly like the old one, bat....
with the new one the pomp doesen't work with the old one run properly.

Any help.
Thanks.

Max

 

[dickh]

Make sure the rubber has not parted from the centre boss - if it has send it back to volvo. Sometimes they need priming when initially fitted, my friend had this problem this year when he fitted a new impellor. After filling up the hose with water it worked fine.

 

[vyv_cox]

I go along with this. There would only seem to be two reasons that a raw water pump will not work at all: either the impeller is not rotating or the suction has been lost. The second is fairly unlikely unless the casing is very worn or the lid has not been fitted properly, allowing an air leak. Check that the drive pin or keyway is in place. With the cover off the pump, rotate the engine and check that the pump rotates. Smear some grease on the impeller and casing interior. Put the cover back on very carefully, with a new paper gasket. Prime the suction pipe with water and hopfully all will be well.

 

[Chris_d]

Sorry if this sounds silly, but did you open the seacock again after changing it?

 

[philwebb]

I heard of a case with an engine overheating and the impeller, on inspection seemed to be perfectly OK.
The problem was that the brass sleeve at the centre had parted company from the rubber "star" Only
the centre was turning, and no water was being pumped.