Oil pump

Oil pumps differ, Twin from Triple. Much has been discussed on the Twin's pump in the previous sub-section because part of it has to be removed in order to get at the primary drive.

If you want to work on the oil pump alone you must remove the ignition contact breaker plate (late SFCs have a trigger mechanism which is easily removed instead) and the advance/retard mechanism and the primary drive cover.

Check the oil pump gears' alignment marks which are necessarily described in the previous section. Remove the oil pump driven gear on the pump, as described. The pump itself sits behind that gear and is held into the crankcase by four setscrews. No gasket is used, but these setscrews should be centre punched into place. Further disassembly is possible and quite obvious. You cannot repair the pump as such, other than to replace the gears and body. These pumps do wear out but it is a long process and something which is unlikely to affect the average life of a machine. Eventually new gears will not 'repair' the effectiveness of the pump in which case, the crankcase half will have to be remetalled.

Replacement is a straight reverse procedure. Centre punch the body fixing setscrews. Replace the oil pump gear in an exact reverse sequence to its removal. Don't force it. Make sure the shim is behind it and that the peg is secure.

NOTE: Never remove either of the oil pump driven gears without checking that the appropriate markings are there. Even if you are going to throw those gears away, in order to replace them, still make the marks.

New gears do not necessarily come with marks, so you must therefore transfer those marks. Purchase Laverda's special tool 61819951 and with it set up the gears so that you can be sure correct fitment has taken place. The tool will help with this; it's obvious. Set the pistons at TDC before you start. Once you are sure it is correct make marks on the gears to enable future straightforward fitment. Although it is not strictly necessary, prime the oil pump with fresh oil once it has been assembled.

NOTE: The pumps gears must be clean, unchipped and not showing any signs of play. The mesh must be tight and there must be no wobble on the spindles. Measurements are given in the Specifications.

The Triple oil pump sits more or less in the same place within the crankcase as the Twin but it does not get in the way of primary drive work. Its crankshaft drive sprocket is behind the primary drive crankshaft sprocket, and quite simply sits on the shaft without anything to hold it on (other than the primary drive sprocket) and is driven by a peg via a cut-out in it.

The oil pump driven gear is held on its spindle by a circlip and shim. Circlip pliers will remove this. No special alignment problems exist because the oil pump drive gear does not control the ignition contact breakers as well.

The oil pump body is fixed in the same way as for the Twins, described previously. The pump's gears work in the same way, the only difference being that the driven gear spindle has two pegs through it, one to locate the drive gear and the other to locate the driven gear.

The same wear check procedure as for the Twin should take place. Reassembly techniques are a reverse sequence to those of removal. You must prime the Triple's oil pump with fresh oil. Both Twin and Triple systems operate under low pressure oil system.

New crankcases always come with new, lapped-in oil pumps.

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