Specifications

25FP-250-00
5
07/2012
Specifications Information and Repair Parts Manual 25FP Series
x
25FP Fire Pump Series
check ball seat bushing (C18) to inspect and/or replace
check ball (C16).
PUMP REASSEMBLY
Seal Reassembly and Installation:
The seal is not normally reused because wear patterns on the finished
faces cannot be realigned during reassembly. This could result in
premature failure. Reuse an old seal only in an emergency situation.
Never mix old and new seal parts. Always replace the shaft seal as a
complete unit.
Handle the seal parts with extreme care to avoid damage to precision
lapped sealing faces.
Clean the shaft sleeve, or replace it if there are cuts or nicks on either
end.
Remove replacement seal from its packaging and inspect the precision
finished faces to ensure that they are free of any foreign matter.
Remove seal spring retainer if so equipped. In this pump the seal
spring is centered on the impeller hub. The spring retainer supplied
with the replacement seal is not needed.
To ease installation of the seal; lubricate the rotating element rubber
bellows and the stationary ring O-ring with soapy water.
1. Install the stationary ring into its bore in the intermediate.
Use thumb pressure to press the ring in until it is fully seated.
Be careful not to damage the seal face.
2. Secure the intermediate to the engine with nuts. Be careful
not to damage the stationary ring on the engine shaft
threads.
3. Slide the rotating portion of the seal onto the sleeve until the
face is just flush with the sleeve end. Slide the sleeve onto
the shaft until the seal faces contact. Continue to push the
sleeve through the seal until the sleeve end seats against the
shaft collar (B17) on the engine shaft.
4. Install the seal spring. Make sure that all components of the
seal are seated squarely.
Install Impeller:
Install impeller shims previously removed if so equipped. Inspect
impeller and replace if cracked or badly worn.
1. Position impeller on end of engine threaded shaft. Impeller
threads on clockwise. Thread impeller onto shaft until it seats
squarely against shaft sleeve or shims. Make certain that the
seal spring is centered on the impeller hub.
For pumps equipped with a balancing ring [25FP23AR] check for free
rotation of impeller. Make sure there is no binding against balancing
ring. A slight rub is acceptable.
Install Discharge Check Valve Body:
1. Install check valve arm into the check valve body, arm pivot
ears fit into cast pockets in body. Arm must pivot with no
binding.
2. Slide flange gasket on check valve body studs.
3. Position check valve body assembly on casing discharge
flange, slide studs into flange holes. Body discharge must
point horizontally to the right when looking at casing suction
inlet.
4. Fasten with four nuts.
Reach in discharge and make certain check valve arm operates
properly.
Install Casing:
If the wear ring or inlet tube was removed from the casing, apply
Loctite® or similar thread-locker to casing bore. Position a new ring or
tube on casing bore. Press ring or tube into bore until it seats squarely
against bore bottom shoulder.
1. Install casing O-ring on intermediate.
2. Install casing on intermediate.
3. Fasten with nuts and lock washers.
Check that impeller rotates freely with no binding, a slight rub is
acceptable, but engine shaft must rotate freely.
4. Install primer vacuum hose female SAE swivel fitting to male
SAE flare fitting attached to fittings in casing suction nose.
Exhaust Primer Reassembly and Installation:
1. Install valve body on muffler outlet [25FP23AR], or slide
nipple [25FP13AR] onto muffler outlet, fix in position with
muffler clamp.
2. Install venturi into valve body.
3. Install ejector body onto venturi.
4. Install ejector jet into ejector body.
5. Install vacuum hose NPT fitting into valve body.
All parts thread on clockwise. Use a high temperature thread sealant.
Do not get sealant on venturi or ejector jet high velocity center port.
6. Install SAE female fitting of vacuum hose onto male SAE
fitting that is part of casing vacuum fitting assembly.
Hand Primer Reassembly and Installation:
1. Install new diaphragm if needed on plunger rod, secure with
fastener.
2. Position diaphragm in body groove.
3. Install lower body half to upper half with screws.
Inspect inlet check ball for wear and correct operation, replace as
needed.
4. Install new inlet check ball, check ball seat bushing, and
reducing bushing into lower body half.
5. Install street elbow and vacuum hose assembly.
6. Install hand primer assembly onto frame mounting bracket
with screws.
7. Install SAE female fitting of vacuum hose onto male SAE
fitting that is part of casing vacuum fitting assembly.