1. There is a drain plug underneath the sight glass in the front of the machine, unless you have the Millenium.

2. How much oil depends on how large the elevation or depression angle the machine is set to. Just add oil until it starts running out the main drive shaft. Put a cookie tin or something under the machine to keep it from spilling all over the floor. Let it settle over night, and the next day make sure the vacuum lock on the sight glass is released. When the oil settles in the sight glass, move the ring just a little below the oil level (about to 1/8 inch or so...) It should be just about the right. When the machine is run and comes up to operating temperature, some oil may leak out the main drive after the machine is shut down for a few minutes because of oil expansion.

That's why I mentioned to move the ring slightly below the level. By the end of the day, it should be apparent how much oil the machine wants to stay happy. A slight drop in the oil level in the sight glass can be expected, but will then level very close to the ring position.

3. For all practical purposes, draining the intermittent cannot be done without removing the unit from the machine. The screws holding the star wheel and shaft casting to the main body do not go all the way through into the intermittent oil reservoir.

About the only way I know how to drain the oil in the movement is to remove it from the machine and dump it upside down. Unless the oil is extremely grungy, it might not be necessary to do that. If the oil is extremely grungy, the movement should be dismantled and cleaned by someone who is completely familiar with intermittent movements. Otherwise, leave it alone.

If the oil is drained from the movement, I would recommend that oil be added by squirting it into the holes in the movement casting. Their location is at the very top of the little "compartment" underneath the main casting lip where the driving gear is located. The holes might be hard to see. There are two holes about 1/8 inch diameter. If the movement is orentiated so the driving gear is at right angles with the deck, the serial number of the movement can be easily read. The holes are slightly to the right, and down about a 1/2 inch or so from the last digit of the serial number. I am basing this information on a movement I have setting along side my keyboard. The actual placement may vary from movement to movement, with respect to the last digit of the serial number.

I would also recommend removal of the sump screen to make sure it is clean. It is necessary to remove the oil pump to do this. After it is determined that the screen is clean, as well as the projector bildge, then re-install the screen and oil pump assy.

BE VERY CAREFUL WHEN RE-INSTALLING THE OIL PUMP! The oil tube nut can be very easily cross-threaded when it is re-connected. If it is accidently cross-threaded, the pump casting will be ruined, and small metal particles will start circulating in the oil bath, which could ruin other things, including the intermittent movement.

A good rule of thumb is this: If it can't be threaded on with light finger pressure, it is in danger of being cross-threaded.

4. How often to give the Simplex XL an oil change depends on the enviroment the machine is running under, and what kind of shape the machine is in. Some people change it every 6 months. Some never change it until it is too late. Some people go by the number of hours of operation. I changed mine about once a year. I honestly forgot what the manual recommends. Maybe some of the other guys can provide a little better figure on that. Just remember oil is cheap as compared to the damage done by not changing it.

My car's owners manual specifies every THREE THOUSAND miles! You get (factory spec) twenty thousand!!!?

Oh well, we run Pro 35s so we have to drain the oil every time we do anything to them!

At least it changes the oil! Besides, as Greg Pauley said earlier, once you get the hang of them, their pretty reliable.

If memory serves, you should add oil to the XL until you can see a steady stream pouring into the intermittent. Personal experience tells me that you WILL need a paint tray under the projector.

I'll admit that I am young, but I've never met a Simplex that didn't leak "somewheres".

The XL does not take much oil. 2 quarts should last you a long time.