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By Norm
#28788
Gwilly,
I have drilled the spigot out on a number of them , not really sure if they breath any better or not but they all seem to be working ok. As soon as they put the breather on top of the oil tank and started fitting catch cans they had to drill the hole in the case
By Alan R
#28809
Hi guys-----------GWILLI I haven't got an APPLE so my WINDOWS are on all the time ---Ho-Ho,Har-Har (Ah-hem!!!!)---- You sure that's a deliberately machined hole ?? Looks like another case of porosity which someone in the factory thought was designed to be there so carried on doing it !!! WTF is that all about then anyway ??(What The Fandango?)...My advice would be to blank that hole off, fit our hosts breather mod. kit ( A 65 will have the original breather at the bottom of the L/H case anyway as it's just the basic Classic 500 with a 5-speed box and an electric leg !!)---)
By Norm
#28813
Alan, you can't block that hole off it is the only way for the crank to breathe because the underbarrel breather is not drilled and unlike the twins that breath into the timing chest even though they had a very restrictive under barrel breather which was inadequate
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By PeteF
#28819
Mmm, a bit of confusion here methinks.
Classic engines breath through EITHER;
The hole between the crankcase and the oil "tank".
OR;
From the breather at the bottom of the barrel.

If you have the oil tank breather design, then there is a pipe from the top of the oil tank that vents to the catch can (if it's still there)
If you have the barrel base breather it vents over the rear chain with a duckbill.
I don't know if any engines had both breathers but you need at least one of them.
So, if you have the barrel base breather you could bung up the oil tank breather and vice-versa (though I can't see any reason why having both wouldn't work OK)
You do need non return valves or duckbills on all breathers however.
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By PeteF
#28820
Oh, and I meant to say.
I once had a 2004 Sixty-Five with a barrel base breather (original - hadn't been drilled out) and no oil tank breather.
Whether it had been comprehensibly rebuilt at sometime I don't know, but it all looked original.
By Terryb
#28832
Hi I have a good news update. I removed the timing cover again and striped the pumps down and check every thing I found nothing wrong with the pumps A suction test was all good but when putting them back together I had fitted two gaskets at one end and three the other. YOU MAY ASK WHY with the new spindle fitted it was to tight with only one gasket but now its been run it was lose. so now I have one gasket each end' And BINGO the oil is not draining from the tank into the sump. I also tested the tank whilst the cover was off by blocking the oil feed to the timing chest. I left the drain plug out put 2 liters off oil in the tank and I had only a drip every 20 seconds or so. NOT A STREAM LIKE BEFORE. so now its had a run again with no smoke on start up. now I will leave it for 24 hours and check the sump again but I feel that it may wet sump a little but not drain the tank. BIG THANKS TO YOU ALL and for the mention of oil escaping through the pump back in this thread and as Arny would say Ill' BE BACK'

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