Sears 390.2508 Operation, Maintaining Your Pump, Draining for Winter, Removing Motor for Service

Models: 390.2508

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OPERATION

Priming the Pump

NOTE: To properly prime the pump, install a pipe tee in the discharge piping, similar to that shown in Figures 1 and 2 on Page 3.

[& CAUTION Never run pump dry. Running pump with-

out water may cause pump to overheat, dam- aging seal and possibly causing burns to persons handling pump. Fill pump with water before starting.

_WARNING Explosion Hazard. Never run pump against

closed discharge. To do so can boil water in-

side pump, causing hazardous pressure ha unit, risk of ex-

plosion and possibly scalding persons handling pump.

To prevent damage to internal parts, do not start

motor until pump has been filled with water. To prime pump:

1.Remove priming plug (Figure 1, Page 3).

2.Fill pump with water.

3.Replace priming plug, using Teflon tape on plug threads; tighten plug.

4.Start the pump. Water should be pumped in 1-2 minutes. If not, repeat steps 1, 2 and 3.

On shallow depths to water (ten feet or less), the pump vdIl more than likely prime the first time after following the outlined procedure.

From ten to 20 foot depths, it is very likely you v_ill have

to shut the pump off and reptime per the outlined pro- cedure several times.

5.If, after priming pump several times, no water is pumped, check the following:

A.Be sure suction pipe is in the water.

B.Be sure suction pipe has no leaks.

C.Be sure the pump is not trying to lift water too high. (See "Piping in the Well," Page 4).

6.As long as foot valve and check valve function correctly and suction pipe does not develop leaks, pump should

not need repriming in normal service.

MAINTAINING YOUR PUMP

Lubrication

It is not necessary to lubricate the pump or its motor. The

motor bearings are lubricated for life. The mechanical shaft

seal in the pump is water lubricated and self-adjusting.

Draining for Winter

When the pump is to be disconnected from service or is in

danger of freezing, it must be drained. To drain it, turn off

power and relieve all pressure on the system. Remove pres-

sure switch tubing from the side of the pump housing. Remove the priming plug to vent the pump. Drain the pres- sure tank; drain all piping to a point below the freeze line.

To drain an air volume control (AVC), remove the tubing

from it and turn the AVC upside down. This will permit any water in the AVC to drain into tank.

Disassembly and Assembly of Pump

&WARNING Risk of electrical shock. Be sure Unit is

grounded and power disconnected before at- tempting any work on pump or motor.

Your SEARS pump is designed for ease in servicing. Should

repair or replacement of the motor or seal be needed, the

pump and piping do not need to be disconnected or dis- turbed.

l. Disassemble ptmap as follows:

A. Disconnect power.

B. Remove pressure switch tube from pump body and allow pump to drain.

C. Remove four hexnuts and lockwashers (Key Nos. 24 and 23, Page 12) which hold the pump body to the motor.

D. Remove motor, seal plate, impeller, rubber pad and diffuser (Key Nos. 1, 3, 7, 8 and 9, Page 12) as a unit.

You may have to pry gently with two screwdrivers be- tween the motor flange and the pump body to sepa- rate pump and motor.

2.Reassembly of pump:

A.install O-Ring gasket on seal plate (Key Nos. 5 and 3, Page 12).

B.Pick up a small amount of petroleum jelly on one fin- ger and spread evenly over seal plate and venturi

O-Ring gasket for lubrication during reassembly. Be careful not to nick or tear O-Ring.

C.Replace motor onto pump body; be sure rubber pad (Key No. 8, Page 12) stays in place on top of diffuser. Remount base on lower studs. Tighten four hexnuts

and lockwashers snugly (35_15 inch-lbs, torque). Do not overtighten.

D.Replace pressure switch tubing and motor wiring.

E.Prime pump according to instructions above.

F.Check for leaks.

Removing Motor for Service

and Replacing Shaft Seal

If it is necessary to separate motor and seal plate, always re-

place the shaft seal. We suggest you purchase this item, U109_A, and have it on hand for future use.

NOTICE: The seal consists of two parts, a rotating member and a ceramic seat. The surfaces of the seal are easily dam-

aged. Read instructions carefully. Remove motor as follows:

l. Disassemble pump per instructions above.

2.Remove diffuser and impeller as follows (Key Nos. 9 and 7, Page 12).

A. Remove screws holding diffuser.

B.Loosen two screws aiad remove motor canopy from motor (Key No. 1, Page 12).

C.Place 7/16" open end wrench on motor shaft flat.

D.Turn impeller counterclockwise when facing it.

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Sears 390.2508 owner manual Operation, Maintaining Your Pump, Draining for Winter, Removing Motor for Service