A: Oil Pipework Series D oil tank

Gary Gittleson

Well Known and Active Forum User
VOC Member
Would you care to clarify this? Overfilled? Before this mod, the only way I could stop overflow at the tank was to run with just a bit over one quart (US) in the system. Are you suggesting that my mod dumps excess oil? That's exactly what I have been trying to avoid. That's not safe for the engine. The tank was far from overfilled, yet there was always oil seeping out the breather hole in the cap. That has stopped. If you had read what I stated, you might have noticed that no oil emanates from the breather hose. The system is now completely self contained and the bike is dry. So is the tarmac.

But no worries. The tarmac I ride on is three thousand miles from yours.
 

Peter Holmes

Well Known and Active Forum User
VOC Member
Gary, Just reread Stuarts article and he states that his modification deals with the problem of overfilling the oil tank, I also note that I did not read the article properly as he states that he vents the excess oil back into the engine via a Series D breather cap, I missed that bit before, so no oil on the road, which is great. As your engine is far from overfilled I just wonder if you have a twin start oil pump fitted that is creating so much vertical splash from the returned oil from the scavenge side of the pump into the oil tank.
 

Gary Gittleson

Well Known and Active Forum User
VOC Member
No, it is not a twin-start pump. I don't seem to be the only one with the splash problem. See David's posts on this thread. But after I made the splash-inhibitor, I still had excess pressure in the tank, which pushed oil out the breather hole in the cap. That's when I decided that I had to vent the oil tank in another way. I thought that if I could vent the tank back to the valve gear at the top of the engine, any oil carried would simply drop through the engine to the crankcase. I also reasoned that since the crankcase is vented with a one-way valve and is normally at a partial vacuum, the extra pressure coming from the tank should be absorbed.

In any case, it all seems to work and I am also now able to run with an adequate amount of oil in the tank with no noticeable loss.
 

John Cone

Well Known and Active Forum User
VOC Member
I found the cure to stop oil coming out through the oil tank filler was to put less oil in the tank, i used to have the oil almost level with the return hole but found if the pump scavenges more oil, whats drained in to the crankcase after a period of standing, it then raises the oil level to high and pushes it out of the cap.
 

Peter Holmes

Well Known and Active Forum User
VOC Member
I found the cure to stop oil coming out through the oil tank filler was to put less oil in the tank, i used to have the oil almost level with the return hole but found if the pump scavenges more oil, whats drained in to the crankcase after a period of standing, it then raises the oil level to high and pushes it out of the cap.
The solution is only to top up your oil tank after a run, that way you will never overflow due the scavenge side of the oil pump overfilling the tank
 

alpinedino

New Forum User
Non-VOC Member
Thanks for your kind comments.
Excuse me translate with google translate.
I deposit oil has no pressure .... but the vent that goes to the chain ejects oil almost 7 meters away from my motorcycle to avoid that I have attached that tube to return the oil to the tank.
the screw inside the tank was fully tightened.
what I do? Can I start the motorcycle without fear of breaking something?
Thanks again
 

b'knighted

Well Known and Active Forum User
VOC Member
Thanks for your kind comments.
Excuse me translate with google translate.
I deposit oil has no pressure .... but the vent that goes to the chain ejects oil almost 7 meters away from my motorcycle to avoid that I have attached that tube to return the oil to the tank.
the screw inside the tank was fully tightened.
what I do? Can I start the motorcycle without fear of breaking something?
Thanks again
This is in the Series D oil tank thread! Do you have a Series D with the oil tank under the seat, or an earlier model with the oil tank under the fuel tank?
 

timetraveller

Well Known and Active Forum User
VOC Member
Hola, estaré en España, cerca de Cartagena, pronto. Si vives en cualquier parte de la provincia de Murcia podría visitarpara explicar cómo funciona el sistema petrolero Vincent.
 

vibrac

Well Known and Active Forum User
VOC Member
Hola, estaré en España, cerca de Cartagena, pronto. Si vives en cualquier parte de la provincia de Murcia podría visitarpara explicar cómo funciona el sistema petrolero Vincent.
Hello, I will be in Spain, near Cartagena, soon. If you live anywhere in the province of Murcia, you could visit to explain how the Vincentian oil system works.
Vibrac adds:
Where is that diagram with all the oil flow and storage areas in a sort of stack?
 

davidd

Well Known and Active Forum User
VOC Member
Oil Diagram.jpg


David
 
Top