Periodic maintenance should be carried out on the purifier to prevent breakdown and blockages caused by hardened sludge and impurities. The purifier can be manually cleaned at intervals of a week (7 days) to achieve premium purity of fuel oil. Daily checks are also advised to check for abnormalities, noise and excessive vibrations. Oil level can also be checked through the sump sight glass. The oil change interval should be at least once a year. Oil like MESH SP 150 can be used. Do not interchange bowl parts of two different purifiers because the major bowl parts carry the machine manufacturing number. The purifier operates in a LEFT HAND THREAD meaning to open is CLOCKWISE and to Lock tight is ANTICLOCKWISE.
To service a purifier,
- Set up the workspace, cover floor plates/tabletop with cartons or clean rags to limit oil spill on the workspace
- Set up the necessary tool set.
- Carry out the stopping procedure earlier stated, do not forget to pull the brakes and wait for the separator to come to a complete standstill before dismantling, close the feed valve.
- Shut off power supply from the purifier panel and the main switchboard purifier feed.
- Remove the bolt holding the safety device with a Ring spanner and remove safety device. Remove nut and shake the inlet housing free from the inlet pipe, do the same for the outlet housing.
- Lift off the frame hood and remove the lock ring with the special tool provided by the manufacture.
- Lift off gravity disc, leader cone and pairing chamber cover ( you will need a screwdriver to lift off the pairing chamber cover from the bowl hood).
- Lift out the inlet pipe, use the special tool to remove the bowl hood, Remember it’s a left hand thread, so; to loosen tension clockwise.
- Use the extractor tool to extract the distributor with the disc stack and top disc attached to it.
- Place in cleaning agent for 2-4 hours or leave in Fuel oil for some minutes, if cleaning agent is used, then use soft brush to wipe. If fuel oil is used, use a clean cloth to clean the disc one by one. Some purifiers have markings so be careful not to interchange the disc or else issues may arise. Alfa Laval MMB 304 s-11 has 80 disc in its disc stack. Disc may reach a total of 150 in some purifiers.
- Remove sludge basket, use a scrapper to scrap off sludge into a deposit bag and discard sediments.
- Clean bowl and water drain tank.
This is a routine maintenance procedure and stops at the bowl hood section. If there is need for complete overhaul,
- Remove seal ring from bowl, and extract the separator frame top part, remove bearings and gasket, fan, buffer holder, rubber buffers, bowl spindle, flat key, ball bearing holder, ball bearing, snap ring, oil pump, belt pulley, O ring and extract frame intermediate part and the final nut. This aspect of the maintenance is not done frequently unless during troubleshooting.
After the maintenance, Replace all parts in the order stated above, grease bearings. Remember it is a LEFT HAND THREAD, closing it will be ANTI-CLOCKWISE. Ensure to lap the bowl hood and the bowl by properly tapping the bowl hood spanner with the tin hammer until the marked circle of the bowl hood and the bowl are at the same perpendicular angle or maximum of 15 Degrees.
When all parts are carefully fixed, observe the purifier and ensure you made no mistake to avoid damaging the purifier and to prevent injuries during start up. I have personally forgotten a Rag inside the bowl body, during startup, the purifier current refused to drop; it had a burning smell and smoke came out from the bowl vent. I had to reopen the purifier to check for abnormalities which led to the discovery of the forgotten rag.
