No reason to use a lot of pressure, but I do tend to think the oil tanks are pretty robust in this situation, Ian. Introducing air to a fuel tank to check for leaks one must be considerably more careful!
G
G
ET: Engine (Twin) Oil change with anti sumping valve
- Thread starter Kevin Emery
- Start date
Glen, sorry broke my own rule of mixing subjects. My reference to pressure was about fuel tanks not oil!
I finished a Venom restoration last year and also fitted a new anti sumping valve and a paper filter, which also adds some additional resistance. Done a 1000mls since then.
The setup works fine (with 20W50) and doesnt seem to obstruct oil circulation in any way. The closing spring of the valve is very soft and gravity helps the oil pump to pull down the steel ball (rubber also available).
The Velocette oil pump is said to be well sized for its task. With a weaker one being used at the limit of its capacity it might be a better idea to omit such a valve.
The 1360 has a new Maughans 2 start. It wet sumps in about 1 week. The Rapides here wet sump in about 2 months. 2 months is very tolerable, no antisump valve needed.
1 week is not tolerable. On checking around at the time, the rapid wetsumping was standard with new Maughans 2 start pumps. No sense in changing for another new 2 start and expecting a better result.
So I purchased a Conway's valve.
On inspecting it I decided not to use it. Hoping that valve will always open against the spring seemed just a little too risky.
Instead, I made up a manual valve with interlock. It is full flow 3/8 when open. The ignition key is needed to start the bike and it is stuck in the valve until such time as the valve is opened.
Changing oil is easy, just open the valve and proceed as with a standard Vincent.
Glen
1 week is not tolerable. On checking around at the time, the rapid wetsumping was standard with new Maughans 2 start pumps. No sense in changing for another new 2 start and expecting a better result.
So I purchased a Conway's valve.
On inspecting it I decided not to use it. Hoping that valve will always open against the spring seemed just a little too risky.
Instead, I made up a manual valve with interlock. It is full flow 3/8 when open. The ignition key is needed to start the bike and it is stuck in the valve until such time as the valve is opened.
Changing oil is easy, just open the valve and proceed as with a standard Vincent.
Glen
Last week I put a tap in a similar position. With lack of use during the Covid lockdown, the oil was in the sump.
I decided that I couldn't trust myself to remember to switch on the oil. I found a small micro switch in my "junk" box and wired this to the magneto kill button. I mounted the switch so that the lever on the tap opened the switch just before the tap was fully open.
I wheeled the bike outside and pressed the start button. Nothing! I checked the petrol was on and chokes set. Still nothing! I stopped and thought about it. I had forgotten to turn on the oil tap. (Did I say something about trusting my memory?) With the tap on it fired up.
Your installation is much neater than mine. Mine is very Heath-Robinson. The rear carb on my Rapide makes the run of the oil pipes more awkward to fit the tap in a place that is still easy to reach. I really need to make up some new longer hoses now that I've proved it works.
I decided that I couldn't trust myself to remember to switch on the oil. I found a small micro switch in my "junk" box and wired this to the magneto kill button. I mounted the switch so that the lever on the tap opened the switch just before the tap was fully open.
I wheeled the bike outside and pressed the start button. Nothing! I checked the petrol was on and chokes set. Still nothing! I stopped and thought about it. I had forgotten to turn on the oil tap. (Did I say something about trusting my memory?) With the tap on it fired up.
Your installation is much neater than mine. Mine is very Heath-Robinson. The rear carb on my Rapide makes the run of the oil pipes more awkward to fit the tap in a place that is still easy to reach. I really need to make up some new longer hoses now that I've proved it works.
Maughan's normally pride themselves on close tolerances, is there any reason why a 2 x Start oil pump would be more susceptible to passing oil into the sump than a single start pump.
Could the oil pump sleeve bore in the case be damaged?
The leakage would have to be bad and occurring at every stop of the pump for me to ever think of a tap but since the sump is 3/8" BSP why not put a petrol tap there? 
at least the consequences of a fault or memory problem with a drain tap is less horrendous and with a strategically placed tray you would get to know the size of the problem.
There is something wrong with the pump on a Vincent if becomes an issue, my vote is it needs looking at
at least the consequences of a fault or memory problem with a drain tap is less horrendous and with a strategically placed tray you would get to know the size of the problem.There is something wrong with the pump on a Vincent if becomes an issue, my vote is it needs looking at
Zero memory required for the valve in the photo.
Bike cannot be started with oil off.
In my view a petrol tap on the sump isn't a good idea.
This requires memory to shut.
Accidentally leave it open and lose all the engine oil as you ride along.
Or hit something on the road and knock it off. Or hit something and have it open up.
Any of those scenarios would cause engine destruction.
Glen
Bike cannot be started with oil off.
In my view a petrol tap on the sump isn't a good idea.
This requires memory to shut.
Accidentally leave it open and lose all the engine oil as you ride along.
Or hit something on the road and knock it off. Or hit something and have it open up.
Any of those scenarios would cause engine destruction.
Glen
Last edited: