BSA Owners' Club Workshop Discussions

The BSA Workshop => Pre War => Topic started by: tonyairconchap on 06 Aug, 2018, 20:39

Title: how much oil do you lose?
Post by: tonyairconchap on 06 Aug, 2018, 20:39
Hello all,  just wondering how much oil does your old bikes lose when out on a run?
I have 2 pints of oil in the sump of my M24/34 sidevalve sloper.  I go for regular 150 mile runs on a sunday  and i need to top up by aprox 1 pint when i get home.
the bikes not burning the oil, no smoke at all. Its leaking mainly from the  base of the push rods. I assume its meant to be oiling the pushrods.
it does not worry me as i carry spare oil on a run and it gives people something to point at when it leaves it mark on the road......nice to see a leaking british bike!
How much oil does your pride and joy lose?
tony
Title: Re: how much oil do you lose?
Post by: tonyairconchap on 07 Aug, 2018, 05:27
My bike is M34/12  got it wrong in the first post sorry
Title: Re: how much oil do you lose?
Post by: BEVANC on 09 Aug, 2018, 10:22
Hi Tony,
Since no one else has offered an opinion, I will put in my tuppence worth - the consumption you quote is around what the 650 cc Panther slopers used to be renowned for doing back in the day - they were oil guzzlers, and they were mostly burning it !  However, with better pistons now available, the oil consumption is minimal - I know this, because I have one.

I would be a bit concerned at the amount of oil you must be leaking.  I realise my BSA S29 ohv Sloper is a different beast to yours, but I have managed to stem the majority of the oil leaks it had, so oil consumption seems pretty low. It breathes into the primary side, so drips a bit out the pressed primary cover seam and I still have a slight leak from the oil pump/sump plate.

Did you establish how your crankcase breathes ?  Is it possible the breathing is constricted somehow and you are getting oil forced out elsewhere ? Or your oil pressure (or oil level) is too high ?  Panthers leak really badly from all over the place if the breather clogs up or if they are filled to the top dipstick mark.

Best of luck !
Cheers,
Bevan
Title: Re: how much oil do you lose?
Post by: tonyairconchap on 09 Aug, 2018, 13:59
Thanks Bevan, always get a good reply from you.
I have been topping up the oil to the top of the dipstick as per the mark on the side of the filler hole.
i am still running the primary chaincase with the breather / chain oiler blocked off as there is no way to restrict it.
so as you say i may be forcing oil out other places, mainly seems to be where the pushrods come out of the casing.
Is oil meant to come out here for pushrod lubrication
my oil pressure runs aout 6psi when warm,  think i remember seeing in the manual that was ok.

i dont mined the oil lose as i know i have a constant supply of fresh going in
what a joy to ride the old bike,  done aprox 1500 miles now , only one cable issue which was fixed on the side of the road.
so many people stop and talk when i park up,  never had that with the rice burner!
cheers for now
tony