The Knowledge - Velocette Owners Club

#900 If you dispense with the tube inside the filter, the entire contents of the filter chamber will drain
back through the oil pump into the crankcase when the engine is stopped. NOT a good idea to remove
it.
#902 Entire contents? The whole half cup-full? As I said, I have never noticed any deleterious effects
whatsoever! Maybe you would if you are one of the traditionalists who insist on using SAE50 oil, but not
with the recommended 20W /50.
#907 And all the crap that has been pumped up into the chamber on the dirty side of the filter? I think
I'd rather leave that in the filter and not draining back through the oil pump whatever oil I use!
#918 I'd suggest that most debris from the oil is already well embedded in the filter felt, and any oil
which does drain back will do so slowly that any metallic pieces large enough to cause damage will
settle to the bottom of the filter chamber. The 'drain' hole (the cross drilling) is not at the extreme
bottom. The oil returning to the sump has to dribble through the .001" clearances in the oil pump, so it
will hardly gush! Having experienced a blocked return due to the existence of this tube, and losing all
the oil as the result of the return pipe subsequently blowing off, I MUCH prefer to dispense with the
tube and risk a little debris returning from whence it came, rather than a complete engine seizure! By
the way, if all the blocked return does is to cause a build up of oil in the crankcase, there is a serious
weakness in the oil pump. The pump cannot revolve at running speed and not pass more oil than could
possibly squeeze through the pump clearances. You will therefore get a very high pressure in the
return pipe and excessive wear on the pump drive gear and worm (creating damaging debris in the
sump!!!).
#911 Both my bikes came without this mystery oil filter tube. Can someone please spec one out so I
cam make one?
#915 Part number A293/2 is what you want - sorry I can't give you dimensions without taking my oil
tank to bits! As I remember, it is a piece of alloy tube which is a push fit over the LE547 filter cap
adapter shoulder below the cross drilling. The OD is just about the same size as the hole in the bottom
filter cap and it is long enough to come to about an inch short of the top cap when fitted. The ¼" stud
runs up inside the tube. It's not unusual for the tube to come off the adapter, perhaps when changing
the filter and either thrown away or simply dropped back on to the stud without being properly located
whence of course it will not do the job it was meant to!
#925 The tube is 0.500 od, 6.850 in length made of aluminum. The wall thickness is approx 37 thou.
The tube is a heavy push fit, light press fit over the fitting at the bottom of the studding; you can clearly
see the step it fits over on the fitting. Bore a piece of ali tube or bar out so that it fits. For what it's worth
I would fit the tube for the following reasons. 1) the filter holds quite a quantity of oil, and this together
with the oil left normally in the bottom of the crankcase may make starting more difficult 2) If you fit the
club filter kit which I recommend www.velocetteowners.com/sparesco/specials.htm you will need it. 3)
if it serves no purpose, Veloce would have saved the pennies by not fitting it I agree that it is unlikely
any debris above a thou will find its way past the oil pump, I just don't like the thought of all that debris
dropping back down.
L #936 When my piston "holed" it also bent things in the oil pump making me rebuild that as well
as needing now to take the engine apart to clean everything out. Would this new filter have saved me?
#938 Unlikely, as the filter is after the pump not before it. What it does is strain out the very fine
contaminants that cause wear in the engine.
L #1055Here I am spannering my Venom racer, trying to reduce all the leaky areas ... I've fitted
a much larger bore to the engine breather - ok. I've drilled the timing case to crankcase hole - ok. But - I
undid the pokey leaky external (1/8 bore !) pipe and fittings to see that the fitting in the crankcase
shows me the side of the flywheel ... now this type of mod is a 'good idea' isn’t it ?! Well, surely if it lets
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