Its shame I cant send the photo as I swear it appears there is no ball and certainly no spring! Id say it looks just like the hemispherical cavity that a ball might sit in and also has what looks like witness/wear rings as to where a ball might have chattered in position over the years.
In centre of this cavity looks like a small hole; only a few mm across which might be the start/end of the oilway. I suppose the acid test would be to put the oil back in the tank and if it is an open orifice/oilway with no ball, the oil would just drain out? Do you think that would work?
Also, would you think it a danger to start the engine with such a valve not in place? I don't know where the oil moves in this engine but it seems close to big end/main bearings. Would it risk these parts to run it.
Finally, this valve /spring not so easy to come by. Do you have any suggestions of a good source?
Not an easy hole to photograph.
The Ball should be easy to find, it's just a 1/4" 0.250" ball bearing
Dranganfly say they have the spring 66-1684, but expensive. My supplier is out of stock. So it would be another thousand off order for me.
You can get the ball and spring from C & D Autos at a reasonable cost..I bought one only last week....The engine will run without it but if your oil pump is worn, which many are now, the engine will rapidly 'wet sump' if left standing...Ian
I have been thinking of installing a manual valve on the oil feed line. At least it will not wetsump while running. The risk is you forget to turn the valve to on position before starting the motor and driving off.
I use to fly airplanes and they had boots or covers on important items. They always had red flags. As a pilot you have a check list. The same can be said for an old BSA.
I'm not normally completely rubbish on the IT front, but how the heck did you upload a picture? Id like to that but after much faffing about i cant seem to find the method?
I'm not normally completely rubbish on the IT front, but how the heck did you upload a picture? Id like to that but after much faffing about i cant seem to find the method?
Cheers
Neil
Hi Neil,
I have just added a short instruction on how to ad photos to posts on the forum. The instruction is on top of the list of threads and it will stay on that location, so it should be easy to find it.
hopefully this maybe the defining post to ask if this looks normal?
I think i have been looking at the wrong orifice mi'lord. I was looking at this in pic below which is different in appearance to that posted by Mark
This is the hole uncovered by the screw underneath the hex nut in pic below but I believe I should be undoing the hex nut itself as in the pic below. Its been a long week :face_with_rolling_eyes:
Incidentally, I dropped the oil tonight; barely 2 pints in the sump but whoops I haven't drained the tank yet so more to come?
Thanks to Bastiaan for the phot upload instructions.
Also, the M20 engine is a 'dry sump' engine so under normal circumstances there should only be a minimal amount of oil in the sump (crank case), with most retained in the oil tank...
The 2 pints you drained from the engine is what has slowly leaked from the oil tank, through the oil pump and past the anti drain valve to the sump while the bike has been standing unused...
That's what people are referring to when they say an engine has 'wet sumped'....Ian