no oil returning to the tank

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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Re: no oil returning to the tank

Postby Mick D » Sun Oct 21, 2018 4:26 pm

Hi

How far have you investigated this? what leads you to believe the pump is shot? Any photos?

Regards Mick

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Re: no oil returning to the tank

Postby willowbedone » Tue Oct 23, 2018 7:55 pm

Hi
I have not stripped the engine yet Tuesday next week is planned day so will know then what has been damaged
will update then
Ian Ian

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Re: no oil returning to the tank

Postby willowbedone » Thu Nov 08, 2018 4:16 pm

Finally stripped the engine and not good news the drive side shaft is loose in the flywheel ! Timing side shaft is damaged and will need replacing The big end feels OK .the crankcases are both fine with minimal damage to drive side
Could the loose drive side shaft have caused this as the timing side bush is very worn
Any advice would be appreciated If anyone has a spare crankshaft would you sell it to me ?
Thanks Ian

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Re: no oil returning to the tank

Postby Mick D » Thu Nov 08, 2018 5:20 pm

Hi Ian

That's bad news, the loose shaft could certainly be the cause of the marking of the crank case and if this is the case I'm afraid the big end and both mains will be b******d too. Hopefully the timing gears have survived.

Any chance you can post some photos?

Regards Mick

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Re: no oil returning to the tank

Postby willowbedone » Thu Nov 08, 2018 6:31 pm

Hi Mick
Yes I will try and post a few photos
The crankcases are OK drive side brass bush in well worn and drive side axle loose in the flywheel I recon not done up tight enough by person unknown who thought he had rebuilt the engine I am at the moment looking for replacement parts Any help would be appreciated
Thanks Ian

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Re: no oil returning to the tank

Postby clanger9 » Thu Nov 08, 2018 6:36 pm

Is the oil pump bore OK?
1966 AJS Model 14 250 CSR "cafe racer"
1993 Ducati 750SS

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Re: no oil returning to the tank

Postby raffles » Thu Nov 08, 2018 8:06 pm

I reckon its time you got to a Sussex Section night where you will I am sure find several very knowledgeable
chaps who will gleefully rub there hands and sort out your problems. Even if its whats wrong, where to go and how to repair it.
Tony

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Re: no oil returning to the tank

Postby willowbedone » Thu Nov 08, 2018 8:15 pm

Oil pump bore looks fine
And yes I agree I need to go to the sussex section meeting and ask lots of questions

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Re: no oil returning to the tank

Postby clanger9 » Thu Nov 08, 2018 8:58 pm

If the oil pump bore is good then I'm sure you'll get it sorted.

Sounds like you need new shafts (drive & timing), new bearings (drive & timing side), oil pump + drive pin.
Bit of a mystery as to why the drive side shaft came loose - hopefully the flywheel is undamaged (check it carefully for cracks).
You'll have to dismantle the crank anyway, so you can check the big end at the same time. Chances are it'll still be OK.
After that, get a decent engine shop to reassemble the crank for you (get them to press the new timing side bush in for you while they're on) and it should all go back together just fine...
1966 AJS Model 14 250 CSR "cafe racer"
1993 Ducati 750SS

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Joined: Mon Nov 16, 2015 6:08 pm
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Re: no oil returning to the tank

Postby willowbedone » Thu Nov 08, 2018 10:10 pm

Yes you are dead right .My problem at the moment is finding some one near to me to rebuild it Is 1956 a year when axles are different to normal

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