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By John R
#1806
I’m reading Gordon May’s book “Overland to India” which is highly recommended. It has a balance of travel related and bike-related stuff which will appeal to anyone with an Enfield. I must admit, owning an’89 350 I have never really appreciated its long distance potential till now!
One thing he describes is oil leakage caused by having the oil filler cap in the wrong position. He says that there is a “fully closed” position which is just used to seal the oil in during transit, and a part open position which allows breathing for normal running. Is this the case with all old-style Bullets?
By Mark M
#22385
Yes! Additionally, all Enfields up to 1955 have a cap with a tiny hole drilled in it (about 1/64th,) which post 55 models don't. This hole also aids breathing, found this out the hard way on my 1953 500 Bullet! REgards, Mark
By p
#22390
Was that the same book in which he advocated changing from 20/50 to straight 50 oil at some stage in his trip....... now there's a man who wants to strip his oil pump drive!
By samj
#22391
Memories!!!! I was driven mad by massive oil leaks until the Forum put me wise to the need to have a small hole in the filler cap of my 1953 Bullet! Result? Still totally leak free after several thousand miles. And Mark was one of the members who gave this advice-thanks again!
By Mark M
#22392
Sam, glad the bike is running well, I'm still searching for missing performance on mine, Next step is to swap the cams! P, the Redditch Bullets have an oil pressure relief valve and consequently are unlikely to strip their oil pump drive unlike the Indian bikes. REgards, Mark
By simon
#22393
I run all my bikes on straight 50. It's warm enough in Northern New Zealand and they run beautifully on it. At the risk of starting another oil debate the word is that many modern especially all synthetic oils are simply too slippery for roller bearing filled old fashioned machinery. No issues with my oil pumps so far.
By Jim B
#22398
Although I cannot offer an explanation for the 2 position filler cap, I struggle to believe the 2nd position is for a transport only mode. Is to prevent oil leaking out but how far would the bike have to be leaned over for oil to come out. I would guess that in normal riding the bike would be leaning over further than during transportation but maybe I am missing something. As a matter of interest my Indian Bullet has a small breather hole in the cap which I assume is standard, so which position should I have the cap.
I remember the radiator caps on several of my older cars also had 2 positions and I always used the 2nd position.
Jim B
By DUFFEL
#22401
I ride a Connie and only have the oil filler cap on the first catch I use the full twist down for checking the oil level
By John M
#22409
My trials Bullet (1956) frequently goes swimming/fording so the cap stays fully closed to keep the water out. I must say that I'm sceptical about the two position theory, but who knows? I think that some Bullets have a breather tube from the filler neck, which would undermine this theory.

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