Pump Pulley
Outside Diameter
(inches)
MOTOR PULLEY OUTSIDE DIAMETER (inches)
2-1/2 2-3/4
3
3-1/4 3-1/2 3-3/4
4
4-1/4 4-1/2 4-3/4
5
5-1/4 5-1/2 5-3/4
6
6-1/2
7
8
9
10
11
12
13
14
2-1/2
1725
2-1/4
1574 1725
3
1431 1590 1725
3-1/4
1310 1460 1604 1725
3-1/2
1210 1346 1480 1615 1725
3-3/4
1125 1250 1375 1500 1625 1725
4
1050 1168 1283 1400 1518 1634 1725
4-1/4
985 1094 1201 1311 1420 1530 1640 1725
4-1/2
926 1030 1131 1235 1339 1440 1543 1650 1725
4-3/4
876
974 1070 1168 1285 1362 1460 1558 1652 1725
5
830
922 1013 1105 1198 1290 1382 1473 1568 1660 1725
5-1/4
788
875
963 1050 1137 1225 1312 1400 1487 1575 1662 1725
5-1/2
750
834
917 1000 1082 1167 1250 1333 1417 1500 1581 1646 1725
5-3/4
715
795
875
955 1032 1113 1192 1270 1350 1430 1510 1575 1650 1725
6
685
760
937
913
990 1065 1140 1217 1290 1370 1450 1509 1581 1653 1725
6-1/2
630
700
771
840
910
980 1050 1120 1190 1260 1330 1393 1460 1526 1592 1725
7
584
648
713
778
843
907
973 1039 1102 1168 1231 1294 1355 1417 1500 1602 1725
8
507
564
620
676
734
789
845
902
959 1016 1072 1132 1186 1240 1312 1421 1509 1725
9
450
500
550
600
650
700
750
800
850
900
950 1006 1054 1102 1166 1263 1342 1533 1725
10
405
450
495
540
585
630
675
720
765
810
855
906
949
992 1050 1137 1208 1380 1553 1725
11
366
407
448
488
530
570
610
652
692
733
774
823
863
902
954 1034 1098 1255 1411 1568 1725
12
336
373
410
446
485
522
560
596
634
671
708
755
791
827
875
947 1006 1150 1294 1438 1581 1725
13
309
343
378
412
447
480
515
549
584
618
652
697
730
763
807
875
929 1062 1194 1327 1460 1592 1725
14
286
318
350
382
414
445
477
509
540
573
605
647
678
708
750
813
863
986 1109 1232 1355 1479 1602 1725
15
267
297
326
358
386
415
445
475
505
534
564
604
633
661
700
758
805
920 1035 1150 1265 1380 1495 1610
16
250
278
306
333
361
389
416
445
473
500
528
566
593
620
656
711
755
863
970 1078 1186 1294 1402 1509`
DETERMINING SPRAY TIP SIZE
As stated earlier in this manual, the output pressure is
determined by forcing the output volume of water
through a certain size orifice or spray tip. Spray tip
size is a very important factor of proper pressure
washer performance, using a tip that is sized too
small will allow overpressurization of the pump and
components. You must know your output GPM and
your desired output PSI to properly select a spray tip
size. To use the chart on page 4, find the desired PSI,
read down the column until you find the output GPM
closest to your pump application. Read to the far left to
find the spray tip number and orifice diameter.
Example:
1000 PSI at 4.0 GPM needs a number 8 spray tip.
Spray tips are available in various spray angles. It is
advisable to have different spray angle tips in the same
size for different cleaning applications. Some spray
tips or nozzles are available with an adjustable spray
angle.
DRIVE SYSTEM
There are three common methods of driving or
connecting the pump and motor/engine. Direct
drive and gear reductions drive require special
components that are matched to the pump and to the
motor.engine, as well as other technical
considerations. A belt and pulley system is the
recommended method of driving the pump because
it allows easy reduction of the motor/engine RPM
to your required pump RPM, as well as absorbing
shocks produced by both the engine and the pump.
5
PULLEY SELECTION
There are many types of belts and pulleys available,
the following is a basic guide. Manufacturer’s
representatives should be consulted concerning your
specific requirements.
From the Motor Pulley Guide (below) determine the
pulley size (A, B or C section), and number and size
(A, B or C section) of belt required. the larger in size
and/or number of belts used will increase the life
of belts. Be sure to consider space limitations of your
finished assembly.
To determine pump pulley size (based on a 1725
RPM motor), find the motor pulley size on the chart
below, follow the column down until you find your
required Pump RPM to meet your requirements, or
the next higher RPM. Follow the column to the left to
find pump pulley diameter.
To Transmit:
HORSEPOWER
“A” SECTION BELT
“B” SECTION BELT “C” SECTION BELT
1 Belt
Single
Groove
Pulley
2 Belts
Double
Groove
Pulley
1 Belt
Single
Groove
Pulley
2 Belts
Double
Groove
Pulley
1 Belt
Single
Groove
Pulley
1
2-1/2 Dia
-
-
-
-
1-1/2
3
-
-
-
-
2
3-1/4
-
-
-
-
3
3-3/4
3 Dia
4-1/2 Dia
3-1/2 Dia
-
5
5-1/4
3-1/2
5
5
-
7-1/2
-
4-1/2
66
5
-
10
-
5-1/4
8
5
8 Dia
15
-
7
10
6
9
20
-
9
-
7
10
MOTOR PULLEY GUIDE
PUMP PULLEY GUIDE (1725 RPM Motor)
