oil supply

[mshaw]

Hi I have a AJS 600cc model 30 1958 I have had a oil pump mod dune by two people have fitted them to bike but do not get a good oil return to oil tank it just full out of return pipe even when revving the bike
I do not know the history of the bike I have changed the oil filter oil pressure vale behind filter
I have put oil down the inlet rock so there is oil in sump still the same
can any one help

[dave16mct]

Are the oil pipes on the right way round?
Dave.

[mshaw]

I hop the pipes are the right way round the nearest oil pipe connection on the engine to the oil tank is on the outside of the oil tank and the inside pipe is connected to the furthest connection on engine Is this the way that they should be ?

[dave16mct]

Yes that's correct. Are the pumps fitted the right way round on the pump plate? The front pump is the feed and should be the narrow one. The rear pump is the return and should be wider.
Dave.

[Groily]

First question - Is the oil level in the tank going down rapidly as the engine runs Mike? And is the crankcase filling up accordingly? If not - and you should be able to see it happening if there's a good feed but no return - I wouldn't run the engine in case it's getting no oil at all to the crank for some reason. Which would be fatal.

A key thing with these is that the bleed from feed to scavenge pump is clear. It's a tiny oil way between the two, in the pump plate, that ensures the scavenge side is primed.

Not sure what mods have been done to yours, but I have had trouble in the past with modded pumps that haven't wanted to scavenge properly. Worth asking, too, if the pump plate has a pressure relief valve built-in, as well as the one you mention in the oil filter chamber. These things can behave very oddly in some circs / combinations.

The lubrication system on these engines is a bit more complicated than some others owing to the pressurised feed side filter chamber and the various valves that adorn it. The right filter for a G11 is also essential. You really DON'T want the oil not to be getting through the filter chamber to the crank and the oil distributor bush for the rest of the engine.

If the pumps ae on the wrong way round, you should get a lot going in - but something less than the correct volume coming back. With the consequence being a full crankcase after a few minutes' running time. If nothing is coming back, suggests that the scavenge side isn't functional (bad), or there's no oil down there for it to suck back up because none got pumped in (worse).

Suggest, if in doubt, removing sump plug to see how much pours out. If only about what you poured down the rocker box, not good. If loads, then the feed side is probably working. But the scavenge isn't.

[mshaw]

Hi I haven not forgot the info you are giving me but I have an other problem my mag as stopped working
I am finding it very hard getting the bottom nut of the mag to replace it
till I replace it I am stumped
I will let you know how I get on

Mike

[Groily]

Hi Mike,
The bottom fastener should be a nut and bolt, accessible when the pinion is off the mag. A slimmish spanner should just about wiggle up the back to hold the nut, or a screwdriver blade or something if need be, as you undo the thing from in the timing cover. Always a bit nadgery, but should be do-able I think. Cheers!

[clive]

A tip given on here which I tried is that before you replace the bolt put a screwdriver slot in the end of it with a junior hacksaw. Then replace the bolt from the magneto side put the first turn of the nut on then use the screwdriver slot to stop the bolt turning why you do the nut up. Does not help you get it off though.

[Ib-Denmark]

oilpump.jpg

Just to add my experience:
See the lump of silicone gasket in the oli cannel