Written by: RS Rev.
01
Sheet no: FFS-485
PUMP OVERHAULING
SFP 250X350 TRANSMISSION PUMP
This instruction is for overhauling of pump side of the SFP 250X350XP(C). For bronze version,
do also see separate instruction FFS-598.
Procedure for dismantling/re-assemble Lip-seal (reference to item numbers on drawing below):
1. If the transmission pump is installed in the engine room;
a. Disconnect piping to Fi-Fi pump suction flange and discharge flange
b. Loosen foundation bolts to Fi-Fi pump feet. Foundation bolts for transmission feet
may be fixed.
2. Remove all 12x nuts item 17.
3. Pull the pump casing off in left direction looking at the drawing below. The pump casing
should slide easy off, but it is possible to use a rod to jack between the studbolt end (item
16) and the transmission flange.
4. When pump casing is off, un-screw the M10 Socket Screw item 11 (CCW-direction)
5. Remove the Impeller Cap item 10
6. Pull off the Fi-Fi pump impeller. It is mounted to the shaft with relative loose fit, so
dismounting should not be difficult. An easy and carefully jacking between impeller flange
and pump casing is allowed. If force is needed, then a jacking tool (2xM16 thread) must be
used connected to the impeller facing the pump shaft end. Othervise pump shaft bearings
may be damaged.
7. Dismount the 2x Hexagon head Screws (item 21)
8. Pull out the Lip seal assembly (Housing with Lip seals) by use of the 2x M8 bolts in
paragraph 7 above. The shaft end shoud be covered by tape/band to protect the sealing
when dis-mounting/mounting.
9. Clean cofferdam and drain holes with fresh water as description, see picture paragraph 9.
10. Exchange wear rings. Ensure drain hole for large wear ring (item 5) is pointing downwards
(not relevant for bronze pump). Cool wear rings alternative heat the seating and knock in
with Loctite 641. The large wear ring to be installed with the 2x45° guide edge inwards
and to be secured with 6x set screws (item 5). Drill and tap M10 half/half in ring/housing.
11. Install the new Lip seal assembly and change of Sleeve
a. Replace Sleeve with o-ring. Ensure cleaned surfaces and assemble with Silicone
grease (typical Molycote 111).
b. Make sure the sealing lips are clean and filled with Silicone grease.
c. Make sure the O-ring outside Lip seal Housing is in place, clean and with Silicone
grease.
d. Make sure the Sleeve where the Lip seals are running on is on place and surface is
smooth, clean and without marks/scratches.
e. Place the Lip Seal Assemply carefully. Make sure the sealing surface is not
scratching in contact with sharp edges as key or keyway.
12. Install back the 2x M8 bolts in paragraph 7 above. Apply Loctite-243 on threads.
13. Make sure Impeller Key is in place.
14. Install back Fi-Fi Pump Impeller. Ensure it is all the way into position.
15. Place the Impeller Cap (item 10) in paragraph 5 above.
16. Fit the M10 Socket Screw for the impeller cap, apply Loctite-243 on threads, tightening
torque 50Nm.
Fire Fighting Systems AS Tel: +47 69 24 49 90
Box 369 Fax: +47 69 24 49 95
N-1502 MOSS e-mail: ffs@fifisystems.com
NORWAY www.fifisystems.com
Page 1 of 5
Written by: RS Rev.01
Sheet no: FFS-485
17. Place back the Fi-Fi pump Casing. Make sure the big O-ring (item 8) is clean, without
scratches and greased with Silicone grease ( typical Molycote 111)
18. Fit all 12x nuts with washers item 17.
19. Align the pump transmission. Final alignment check must be done after bolted to
foundation and Fi-Fi pump Suction/Discharge flanges are connected. Make sure no pipe
stress is transferred to the pump flanges. Check alignment is withing tolerance.
Reference drawing wit item nos.:
Fire Fighting Systems AS Tel: +47 69 24 49 90
Box 369 Fax: +47 69 24 49 95
N-1502 MOSS e-mail: ffs@fifisystems.com
NORWAY www.fifisystems.com
Page 2 of 5
Written by: RS Rev.01
Sheet no: FFS-485
Paragraph 2 & 3 Paragraph 4 & 5
Paragraph 5, impeller Cap removed: Paragraph 8,Lip seal assembly shown
Fire Fighting Systems AS Tel: +47 69 24 49 90
Box 369 Fax: +47 69 24 49 95
N-1502 MOSS e-mail: ffs@fifisystems.com
NORWAY www.fifisystems.com
Page 3 of 5
Written by: RS Rev.01
Sheet no: FFS-485
Paragraph 10, Lip Seal assembly Paragraph 8, Lip seal disassembled
Fire Fighting Systems AS Tel: +47 69 24 49 90
Box 369 Fax: +47 69 24 49 95
N-1502 MOSS e-mail: ffs@fifisystems.com
NORWAY www.fifisystems.com
Page 4 of 5
Written by: RS Rev.01
Sheet no: FFS-485
Paragraph 9, Flushing cofferdam
Ensure holes are open under oil cooler and drain hole. Clean and use fresh water for flushing. Take care
of “Oil seal” inside cofferdam when cleaning.
Fire Fighting Systems AS Tel: +47 69 24 49 90
Box 369 Fax: +47 69 24 49 95
N-1502 MOSS e-mail: ffs@fifisystems.com
NORWAY www.fifisystems.com
Page 5 of 5
