Lionel postwar motor, 675 slow to get up to full speed

@mlaughlinnyc posted:

This is about the problem that I mentioned in the Lionel 675 problem topic.  As I've thought about it, it's not a 675 problem but one that is probably about any early post war 6 wheel motor.

I have a 675 that I've overhauled mechanically so it's a great smooth runner.  I used LaBelle 124 PFTE on the gears and LaBelle oil on everything that turns.  Tonight after it being idle for several days, I put it on the track and turned up the throttle to the usual operating voltage and it hardly moved.  With my RW at the full 19 volts it started to move and the speed gradually increased.  After two laps around my 12 foot test loop, it was running nicely at 13-14 volts and at 18 it would fly off the curves.

My question to the group - why is starting so slow after a few days of not running ?

I'll gladly admit that I'm no expert on early post war locomotives, which is why I read you thread with curiosity.  I do have some experience with old electric motors and gears.  It might be helpful to know more about the procedures you used when mechanically overhauling the motor, particularly if you de-greased all the friction surfaces and which worn parts you might have replaced or resurfaced.

My first thought about your description of how after sitting for a while it was slow to start but gradually increased in speed and electrical efficiency, could be related to a build-up of old hardened grease somewhere in the drive train. If so, after the parts and grease warm-up a bit, the friction would be reduced.

I've seen the same kind of thing happen in old fan motors that have old semi-hardened oil and dust in the armature and bearings.  At first they barely turn, but after warming up for a few minutes seem to run fine.  Adding more lubricant seemed to help at first, but then after sitting for a few days, they would start-up slowly again.

Thanks, that could be the problem.  When I got that motor, I could barely turn the wheels.  I did let the motor sit in a Naptha bath for many hours.  Maybe that wasn't enough.  I'll try letting it sit in the grease solvent for 24 hours and rinse and lubricate again.  I'll let you know if that fixes the problem.

Many of the Lionel’s post war bearings were Oilite. This is a porous material which is oil impregnated using a vacuum/pressure procedure.   It is recommended that these bearings not be soaked in solvents to avoid stripping the impregnated oil out of them. These bearings can be cleaned with a light oil and then soak them in an oil bath for several days, if possible, to renew some of the oil. Do not use grease on these bearings as it will plug up the pores. The Oilite web site has a procedure for reoiling these bearings, but t do not think it is practical for the small bearings used in Lionel trains.

Is this consistent with Lionel's lubrication instructions which never showed any significant variation that I have noticed.