I don't think the thinner oil will run hotter, it might even run cooler, but whatever the temperature it will be thinner. The oil circulation rate in a Vincent is very slow so the oil in the tank doesn't get very hot. The oil at the hot places in the engine like in the head and the pistons must get hot. Around the intake and exhaust guides it is always going to be hot. If the oil is thicker less will go down there.
A: Oil Pipework Oil consumption
- Thread starter robin stafford
- Start date
The heat in oil comes from resistance mostly, so compare any Brit twin Triumph, BSA, etc......These run high oil pressures with a common shape oil tank.......The Vincent runs almost nill pressure and has an oil tank that acts like a big heatsink with plenty of air flow around it.......I read somewhere that a Vin is flat out getting an oil temp over 70 degrees Celsius on a hot day........So more of an issue with sludge forming in the base of the tank from moisture build up.........You want oils in the viscosity of 10 to 50 weight.......anything higher is too thick........I run a 15/w 40 diesel oil in mine which is still quite thin, but because of the cams in my engine it needs to spin quite fast when i kick it over or else it just wont fire up....... this no matter what kind of ignition I try, either coil or magneto made little to no difference........I don't ride a huge amount, perhaps 1000 to 1500 miles per year, so i just change the oil every 1000 or annually, the oil tank stays nice and clean, contents of the timing chest looks like new.........Good enough for me.
Diesel engine oil is quite nice with a lot of detergent additives , so your engine will stay very clean inside. Multigrade types are great for starting by kickstarter certainly , and perfect for riders who don´t garage the bikes for many months. In that case a multigrade will drain a lot more down than a monograde like SAE 40 or 50. So monograde will stick better to the cams over long periods of no use so less wear in these critical components. But then, you can only do compromises many times.
Vic
Vic
Not so thin when you are trying to start your bike at 4 C at Shadow Lake, Ontario in early October!
Opposite problem to here.........You need to kickstart your bike in the cold to get warm.........after a half a dozen kicks here and you dissolve into a pool of sweat on the ground........
I have been reading lots of posts on lubrication problems the prof had problems with the return supply, Starting the bike the looking at the return the oil spurts out within 8 seconds blipping the throttle looking at the crankcase breather nothing comes out for about 2 minutes letting the bike tick over after a minute or so oil starts drip out looking at the return nothing is returning only when I rev does the oil return I have a single start pump Do you think no restricters in the barrel feeds and the rocker feeds to much oil is building up at low rpm flooding the engine also when ticking over for some time revving, the return side goes into over drive plus some smoke from the exhaust , a few blips then it clears I think the level of oil is to high in the crankcase
Robin
One thing to look for is oil pump cap OP33. If the threads are not sealed properly then this end of the oil pump is the return and the pump rather than lift the oil from the sump can suck air past the cap threads instead and so slowly the oil in the sump rises.
One thing to look for is oil pump cap OP33. If the threads are not sealed properly then this end of the oil pump is the return and the pump rather than lift the oil from the sump can suck air past the cap threads instead and so slowly the oil in the sump rises.
Hi Simon I remember sealing the brass plug with hylomar when screwing it up
Robin,
It is hard to figure out the problem from the symptoms. It could be possible that the symptoms are not important.
I mention this because the scavenging portion of the pump will evacuate the scavenging chamber at a very high rate. I understand this scavenge pumping rate to be much higher than the rate that the front of the oil pump supplies oil to the chest.
The revving of the engine will dump some oil in the scavenging chamber (from the flywheels slinging more oil) and it will get pumped up to the tank very quickly. This may be the "overdrive" that you are witnessing. The smoke in the exhaust could be from oil in the tunnels flooding the valve guides momentarily. The oil supply to the chest is "non-interruptible", while the oil supply from the scavenging chamber is "interruptible" because the scavenging chamber can be run dry or close to it during idle.
David
It is hard to figure out the problem from the symptoms. It could be possible that the symptoms are not important.
I would think the answer to this is no. I cannot remember an owner with this type of problem. But your two questions are related:
I think that you are leaving out some of the oil movement in the case. When the sump fills with oil during non-use, upon start-up the sump would certainly be overfilled. You describe the symptoms of sumping, but I can see that you think it is happening with the engine running. When the engine is running the oil that makes its way to the sump is picked up by the flywheels, scraped off the wheels into the scavenge chamber at the rear of the sump. The oil that is carried into the scavenging chamber is pumped from the scavenging chamber by the bottom of the oil pump and pushed up the oil line that goes to the rockers on its way back to the tank return.
I mention this because the scavenging portion of the pump will evacuate the scavenging chamber at a very high rate. I understand this scavenge pumping rate to be much higher than the rate that the front of the oil pump supplies oil to the chest.
The revving of the engine will dump some oil in the scavenging chamber (from the flywheels slinging more oil) and it will get pumped up to the tank very quickly. This may be the "overdrive" that you are witnessing. The smoke in the exhaust could be from oil in the tunnels flooding the valve guides momentarily. The oil supply to the chest is "non-interruptible", while the oil supply from the scavenging chamber is "interruptible" because the scavenging chamber can be run dry or close to it during idle.
David
That 3/8" whitworth grub screw bellow the oil pump brass cap can leak too, especially if someone has got at it before.......If it leaks oil it will suck air........Just a small one to look at.