Oil return

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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davehutch
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Oil return

Post by davehutch »

Finally got my G2 running Nice taking Don’s advice taking out air screw and blowing compressed air down pilot jet that I didn’t know was there seems to have done the job even though the bore is 1 1/8. Thanks Don!
Now got big new problem oil does not seem to be returning back into engine. I can remember taking off the filler cap and seeing oil returning through hole just above oil level Is that right?. It is not happening now. Need more advice Thanks again Dave
----Only a biker knows why a dog sticks his head out of a car window.
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Biscuit
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Oil return

Post by Biscuit »

Don't run the engine unless you can answer 'no' to this question - have you removed the pump plunger guide pin since you last saw the oil return?. In any case it would be wise to check the condition of the business end of the pin. Don't turn the engine whilst the pin is out. It would be wise to check whether the plunger is rotating and reciprocating. Remove the right hand cowl and the oil tank and you will see the end of the pump hidden behind a cap, complete with an 'o' ring, this is kept in place by a screw, whip it out and you will see the end of the pump plunger. If you are happy with the engagement of the guide pin, rotate the engine and check the movement of the pump.

All this is belt and braces, but the damage caused by a non rotating/reciprocating pump isn't something you need.

And yes the oil returns through this hole after an extremely tortuous journey. bearing mind the engine/tank holds less the than the silly gearbox, the oil level is best kept up the return hole.

Apologies if you rebuilt the engeine and know all this anyway.;

Edited by - Biscuit on 16 Aug 2008 3:04:18 PM



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davehutch
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Oil return

Post by davehutch »

Thank you for your advice. I haven’t touched the engine since I last seen oil returning, and haven’t had the engine to bits at all. And noticing the oil not returning is while revving it in my garage I have not took it out. May be I noticed it returning after I took it out last time. Should it return while just revving. ? I only know the basics and learning.
Thanks Dave
----Only a biker knows why a dog sticks his head out of a car window.
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Biscuit
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Oil return

Post by Biscuit »

It should return whilst just revving. I would feel very suspicious about this. Have a close look at the guide pin I mentioned, is there a spacer under the head that shouldn't be there? The Lightweight I looked at had such a spacer because the idiot (not the then owner) was unable to get the pin in the groove. Result - new crank cases, pump plunger, luckily the timing side shaft survived.



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davehutch
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Location: LEICESTERSHIRE UK

Oil return

Post by davehutch »

Thanks for your Help Allan,
I will start to investigate at some point this week. When I start investigating I will be back on for more advice thanks again.
Dave
----Only a biker knows why a dog sticks his head out of a car window.
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davehutch
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Location: LEICESTERSHIRE UK

Oil return

Post by davehutch »

I have found this information in my workshop manual:
Oil fails to return from the sump. Take out the crankcase filter and verify that the cap in the end of the filter tunnel is in position and not sealing the oil return passage from the sump.
How do I get the cap out and how do I know it is in right position? Is it worth checking as it has not been touched?
----Only a biker knows why a dog sticks his head out of a car window.
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Biscuit
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Oil return

Post by Biscuit »

Sometimes the cap comes out with the filter, sometimes not. If it remains in, hook out with a 1/16" or 3/2" piece of wire/rod with a right angled bend at the business end. Clean the cap and the filter tunnel, push it back in squarely and peer down in to the gloom and see where the cap is in relation to the hole at the bottom.



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davehutch
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Oil return

Post by davehutch »

Thanks Allan
----Only a biker knows why a dog sticks his head out of a car window.
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davehutch
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Oil return

Post by davehutch »

Unfortunately Filter and everything seems ok. So I will have to investigate pump! Will let you know how I get on
----Only a biker knows why a dog sticks his head out of a car window.
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davehutch
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Oil return

Post by davehutch »

I have removed the oil tank. Not sure what to undo next .I can see 2 bolt heads in side oil tank, 1 at the front and 1 towards the back going in a about 45 deggres.It does not seem to be like Allen explains by ( you will see the end of the pump hidden behind a cap, complete with an 'o' ring, this is kept in place by a screw,) Is it behind one of these bolts.? Is that the cap? It is more likely to be like Allan explains it just me I bet HELP!!
----Only a biker knows why a dog sticks his head out of a car window.
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