MG style 10EE does not get to full RPM

Finally got back to the MG 10EE that I replaced a forward starting relay in about 18 months ago (bad coil). This was replaced from another 10EE whose owner had converted to VFD. I have not really needed the lathe until now. Unfortunately, the spindle only gets up to about 800 RPM in forward speed. This is not a high speed machine, tach only goes to 2500. Interesting thing is when I go to reverse the spindle the chuck speeds up and probably achieves the full RPM. Dont know for sure because the tach is not registering, but it is MUCH faster than the forward speed. This is a 1950 production lathe with a turret, no quick change gearbox. Incidentally, this machine did sit for years before I got to it to replace the forward relay. Any insight would be helpful to say the least. DC power systems are not my thing, so please act like I dont know crap. You are probably correct.

Biolog said:

Finally got back to the MG 10EE ... Unfortunately, the spindle only gets up to about 800 RPM in forward speed. ... Interesting thing is when I go to reverse the spindle the chuck speeds up and probably achieves the full RPM. ...

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That sounds like a brush timing issue. You probably also have a lot of sparking on the spindle motor commutator in one direction.

See this post for information about adjusting the brush timing:
Cal
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Thanks Cal! I think I follow the gist of this. Will have to study it for a bit though. If I can access the front of the motor without too much interference from the front wiring/relay panels I will give this a try next week. Was wondering about brushes, but the apparent running ok in reverse fooled me a bit. Appreciate your timely assistance!

The big DC control panel next to the spindle motor is on hinges and will swing partially out of the way. You can also remove the top hinge and lay it flat on the floor, face down, but I don't recommend running the machine with it like that.

Cal
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Ok. Thanks for the tips. I have put off working on this for a while, but it would be really handy for small jobs that dont work that well in the larger lathes. No single point threading on this machine, but I dont think I will miss it.