BSA Owners' Club Forum

The BSA Workshop => Singles => Topic started by: SUPERGRUMPS on 23 June, 2017, 10:56:06

Title: Internal Incontinece
Post by: SUPERGRUMPS on 23 June, 2017, 10:56:06
I have just removed the inner crankcase cover from my C15 (Distributor model), and found it full of oil. I understand this should not be the case and the fault lies with the NRV on the feed side. Unfortunately this can only be accessed by splitting the engine. has anybody else had similar problems and overcome it by fitting a extra NRV or solenoid valve on the feed line? as I would prefer not to dismantle the engine to get at the existing valve.
Title: Re: Internal Incontinece
Post by: om15 on 23 July, 2017, 11:04:57
I had the same problem with my 1964 C15, I thought that I would do more harm than good by splitting the engine, so I bought a small brass gas tap with an internal bore of 3/16" and fitted directly below the oil tank in the feed line, when ever it is parked up I shut it off to prevent wet sumping.
Title: Re: Internal Incontinece
Post by: om15 on 23 July, 2017, 11:28:22
Here it is
Title: Re: Internal Incontinece
Post by: SUPERGRUMPS on 27 July, 2017, 19:27:00
Thanks OM15, but its a bit risky, what if you forget to turn it on. I managed to get a anti wet sumping valve, which is basically a non return valve, that works as follows. when the engine is running the suction of the pump is enough to pull the disc of the seat and allow oil flow, when the engine is off, there is equal pressure either side of the disc, thus preventing oil flow. I have fitted this, however still not sure whether it works.
Title: Re: Internal Incontinece
Post by: ANDY HIGHAM on 27 July, 2017, 21:38:11
Gear pumps are great at producing pressure not so good at sucking. A spring loaded valve between the tank and pump could starve the engine of oil, an on/off tap is easily forgotten with disasterous results. BSA fitted an anti wet sumping valve, if it's not working find out why and repair it rather than a risky botch job
Title: Re: Internal Incontinece
Post by: om15 on 28 July, 2017, 19:51:12
Here is a better view of an oil shut off valve, fitted to a Matchless to prevent wet sumping. As mentioned the results of failing to select to flow can be expensive.
I only switch off for a prolonged lay up, over winter for example.