You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
3 PT SERIES PUMPS PT / PG / PD REPAIR<br />
3.1 Description and Operation<br />
PT Series Pumps use an impeller (1) and volute (2) to<br />
create the suction and discharge pressures required for<br />
pump operation.<br />
The impeller is bolted directly to the engine drive shaft (3)<br />
and rotates inside the volute casing. Water is drawn into<br />
the pump inlet (4) by the low pressure area created at the<br />
eye of the impeller. Vanes on the impeller move the liquid<br />
into the volute where it is gathered and directed to the<br />
discharge port (5).<br />
A moveable tapered ring (6) set inside the volute, can be<br />
shimmed to maintain close tolerances between the volute<br />
and impeller to maintain pump efficiency.<br />
A mechanical seal (7) mounted behind the impeller,<br />
prevents water from following the engine drive shaft and<br />
seals the rear of the pump housing to prevent leakage.<br />
An oil cavity in the pump case holds the seal lubricant,<br />
reducing wear to seal surfaces.<br />
4<br />
3-2<br />
8<br />
2<br />
6<br />
The flapper valve (8) at the pump inlet, closes when the<br />
pump stops. This valve seals the inlet port and prevents<br />
the prime water in the suction hose from being lost.<br />
Pump case is easily filled with water by removing the<br />
priming plug (9).<br />
1<br />
5<br />
7<br />
9<br />
3<br />
1033SD43
Change language