Crane DEMING 7365N-X54-95-30N, Installation And Operation Manual

13

C-3.2) Insulation Test:

Before the pump is put into service, an insulation (megger) 

test should be performed on the motor. The resistance values 

(ohms) as well as the voltage (volts) and current (amps) 

should be recorded on the start-up report. Pumps/systems 

with an insulation value of less than 5 M-Ohms should 

be investigated for moisture or damaged cables before 

proceeding.

C-3.3) Pump-Down Test:

After the pump has been properly wired and lowered into the 

basin, sump or lift station, it is advisable to check the system 

by filling with liquid and allowing the pump to operate through 

it’s pumping cycle. The time needed to empty the system, or 

pump-down time along with the volume of water, should be 

recorded on the start-up report.

IMPORTANT! THE MAXIMUM ALLOWABLE STARTS 

PER HOUR IS 15, EVENLY SPACED.

SECTION D: PREVENTATIVE MAINTENANCE

As the motor and seal chamber are oil-filled, no lubrication or 

other maintenance is required, and generally Crane Pumps & 

Systems will give very reliable service and can be expected 

to operate for years of normal sewage pumping without 

failing. However, as with any mechanical piece of equipment 

a preventive maintenance program is recommended and 

suggested to include the following checks:

1)  Test moisture detector control “Test Switch” for 

continuity of circuit. Water in the seal chamber will

energize a seal leak warning light at the control 

panel. This is a warning light only and does not 

stop the motor. It indicates the seal has leaked 

and must be repaired. This should be done within 2

or 3 weeks to prevent further damage. See section

   C-2.2. 

2)  Inspect impeller and body for excessive build-up or

clogging and repair as required per section E-2. 

3)  Inspect outer shaft seal and replace as required per

section E-3. 

4)  Check motor for ground leakage and proper amp 

   draw. 

SECTION E: SERVICE AND REPAIR

NOTE: All item numbers in ( ) refer to Figures 8, 9 & 10.

WARNING ! - Electrical power to the pump 

motors must be disconnected and locked 

out to prevent any dangerous electrical 

hazards or personnel danger before any 

service work is done to the pump.

CAUTION ! - Operating pump 

builds up heat and pressure; 

allow time for pump to cool 

to room temperature before 

handling or servicing.

E-1) Lubrication 

E-1.1) Checking Oil

1. Place pump on it’s side, and drain oil into a clean, dry 

container. 

2. Check oil for contamination using an oil tester with a range 

to 30 Kilovolts breakdown.

3. If oil is found to be clean and uncontaminated (measure 

above 15 KV. breakdown), refill the seal chamber as per 

section E-1.2.

4. If oil is found to be dirty or contaminated (or measures 

below 15 KV. breakdown), the pump must be carefully 

inspected for leaks at the shaft seal, before refilling with oil. 

To locate the leak, perform a pressure test as per section 

E-1.3. After leak is repaired, refill with new oil as per 

section E-1.2.

E-1.2) Replacing Oil:

Seal Chamber - Drain all oil from seal chamber and dispose 

of properly. Refill with (see parts list for amount) new cooling 

oil as per Table 2. An air space must remain to compensate 

for oil expansion. Set unit on side and fill.

IMPORTANT! - Do not overfill oil. Overfilling 

of seal chamber with oil can create 

excessive and dangerous hydraulic 

pressure which can destroy the pump 

and create a hazard. Overfilling oil voids 

warranty.

E-1.3) Pressure Test:

Seal Chamber - Before checking the pump for leaks around 

the shaft seal, the oil level should be full. Remove pipe plug. 

Apply pipe sealant to pressure gauge assembly and tighten 

into pipe plug hole. Pressurize motor housing to 5 P.S.I. 

Use a soap solution around the sealed area and inspect 

joints for “air bubbles”. If, after five minutes, the pressure 

is still holding constant, and no “bubbles” are observed, 

slowly bleed the pressure and remove the gauge assembly. 

Replace the pipe plug using a sealant. If the pressure does 

not hold, then the leak must be located.

CAUTION! - Pressure builds up extremely 

fast, increase pressure by “tapping” air 

nozzle. Too much pressure will damage seal. 

Do Not exceed 10 P.S.I. in seal chamber.

TABLE 2 - COOLING OIL - Dielectric

SUPPLIER

GRADE

BP

Enerpar SE100

Conoco

Pale Paraffin 22

Mobil

D.T.E. Oil Light

G & G Oil

Circulating 22

Imperial Oil

Voltesso-35

Shell Canada

Transformer-10

Texaco

Diala-Oil-AX

Woco

Premium 100

E-2) Impeller and Volute Service: 

E-2.1) Disassembly and Inspection:

To clean out the volute (10), or clean out or replace impeller 

(6), disconnect power, remove cap screws (2) then vertically 

lift motor assembly from the pump body (10). Clean out the 

volute, if necessary, clean and examine impeller (6) for pitting 

or wear, replace if required. To remove Impeller (6), remove 

cap screw (8) and washer (8A). The impeller is keyed onto 

the shaft with a square key (7) and to remove, pull impeller 

straight off the shaft using a wheel puller if required. Inspect 

o-ring (9) and replace if cut or damaged. Before reinstallation, 

check the motor shaft and impeller bore for damage.