I did not build the engine on my '65 G80CS, today I discovered the crank case full of oil, it has the Norton oil pump, there looks to be a check valve above the oil union at the lower casing, without taking the engine to bits, is there a common problem with this valve? I know that a lot of engines are prone so wet sumping.
Cheers.
Re: Crank case full of oil G80CS
Posted: Sat Sep 30, 2023 7:17 pm
by g80csp11
im told that the norton oil pump is prone to wet sumping , how long has the bike been standing ?
my norton oil pump on a Atlas engine can wet sump over 2 pints if left for a couple of weeks
Re: Crank case full of oil G80CS
Posted: Sat Sep 30, 2023 7:25 pm
by Red Gauntlet
OK about 3 weeks, looks like normal then?
Re: Crank case full of oil G80CS
Posted: Sun Oct 01, 2023 9:34 am
by g80csp11
I have a late G80 engine with Norton pump , and the previous owner fitted a tap in the oil feed . I guess for the same reason
Ive not done it or inspected , but on Commando/Atlas pumps which i believe is similar there are a few checks you can do that might help
Re: Crank case full of oil G80CS
Posted: Sun Oct 01, 2023 9:45 am
by Red Gauntlet
Judging by the rest of the bike the PO was a bit of a bodgit and scarper merchant, I will almost certainly have to strip the engine and rebuild it properly at some point, they didn't come out of the factory wet sumping... or did they? Judging by the video from Andover Norton it looks like they did...
Re: Crank case full of oil G80CS
Posted: Mon Oct 02, 2023 9:36 am
by mdt-son
A gear pump will leak, the question is how much. There is no cure, just remedies.
A brand new pump should alleviate the need for draining the sump for 8 weeks or more. Worn pumps can be reconditioned to a certain degree, and there is also the modification offered by AMR which will remedy leakage through the spindle.
Let's face it, oil pumps do wear. Reducing the leak to a minimum requires fitting a new pump.
