Author Topic: Oil leak not where I thought it was from.  (Read 406 times)

Offline Minto

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Oil leak not where I thought it was from.
« on: 17.03. 2021 20:00 »
I thought the main leak I had was coming from the crankcase join between where the engine bolts to the box and I was expecting to see a shed load of oil come out from that void when I unbolted the box... Nothing, nice n dry inside... But there was a lot of oil all down the back of the engine behind the magneto, over the cam area, around the outside of the square gear box flange, on the top cylinder barrel fin, the cylinder head fins, and the rocker box gasket is a total mess of splits and voids. I've already got some copper rocker gaskets to try (thanks TT John). I'm thinking that maybe all or most of the leaks I thought I had might be attributed to this. It was dropping a lot of oil, and it was blowing/running/dripping everywhere making it very difficult to trace.
Onwards.
Jase
52 A10 plunger
Aprilia RSVR

Offline AdrianJ

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Re: Oil leak not where I thought it was from.
« Reply #1 on: 17.03. 2021 20:12 »
I had this. It was badly fitting seals on the rocker oil feed banjos. Running down and getting everywhere. Completely cured with Dowty washers.
'53 Plunger Flash and Steib S500, ‘66 LE Velocette, ‘53? Winged Wheel


Online Klaus

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Re: Oil leak not where I thought it was from.
« Reply #2 on: 17.03. 2021 20:23 »
Or the oil feed banjo has a crack itself, so my experience. Only visible when its bolt off, try to twist it.

cheery Klaus


If you think, everything is under control, you are not fast enought.

BSA DB34 Goldstar, BSA A10 Road Rocked, BSA A7 Shooting Star, BSA M33, BSA M24, Kawa W650

Offline Minto

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Re: Oil leak not where I thought it was from.
« Reply #3 on: 17.03. 2021 21:30 »
I'd never noticed any leaking from the rocker feed components, but definitely worth further investigation. Cheers for the suggestions.
Jase
52 A10 plunger
Aprilia RSVR