Author Topic: oil return in tank  (Read 1211 times)

Offline old PJ

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oil return in tank
« on: 25.11. 2007 10:35 »
Hi all i have just finnish my A10 engine rebuild and after starting the bike up the oil return was good after a min of ticking over i did put plenty of oil around when building up and the bike sounds very nice and runs lovely the only problem is that the oil that comes out the return pipe in the oil tank is full of air and look like cream is that normal   its very cold here at the moment so the oil is very cold i havent run the bike to get it hot at the moment.


Online bsa-bill

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Re: oil return in tank
« Reply #1 on: 25.11. 2007 10:58 »

Return side of the oil pump has higher capacity than the feed side so will always pump oil air mixture, don't know about the cream colour though, might indicate water ( condensation if it's that cold ) in the oil.
Suggest you change the oil then try again

All the best - Bill
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Online RichardL

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Re: oil return in tank
« Reply #2 on: 25.11. 2007 14:54 »

I also found it odd that return oil was somewhat creamier looking that the rest, however, I believe that is because the bubbles in the oil lighten the apparent color of the oil. Additionally, if you used white assembly lube when putting the engine together, that might make the initial circulation lighter in color. While I don't think the creamy appearnce is a problem, it can be a good idea to idea to drain oil after intial startup, just to see if there is anything bad floating around.

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Offline LJ.

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Re: oil return in tank
« Reply #3 on: 25.11. 2007 16:36 »

I also get this effect when pouring a nice dark ale into glass! It's what we English call a good head on the brew, none of this of course is wasted, it goes down well every time... think i'll have another now while reading todays posts!

Cheers *beer*
Ride Safely Lads! LJ.
1940 BSA M20 500cc Girder/Rigid- (SOLD)
1947 BSA M21 600cc Girder/Rigid-Green
1949 BSA A7   500cc Girder/Plunger Star Twin-(SOLD)
1953 BSA B33  500cc Teles/Plunger-Maroon
1961 BSA A10  650cc Golden Flash-Blue
1961 BSA A10  650cc Golden Flash-Red