Have the belts been replaced? The belt part numbers for the SFT100W are
RCA part number 149045 crosses to PRB part number FR2.0
RCA part number 152751 crosses to PRB part number FR21.5
Apparently, one of each in the unit.
This is from an RCA goldenrod bulletin I got at a service seminar - it seems the part numbers were harder to find than the service data. I've never opened a CED player, although I have one - not sure of the model. If your unit is running on original belts, it could be a starting point. I'll keep scouring my RCA lit for more.
And there's this from CEDmagic:
http://www.cedmagic.com/tech-info/repair-solutions.html
Player Category: F/G Chassis Fault: Improper Turntable Speed
Symptom(s):
Image on TV exhibits intermittent color fade wherein it changes from being in color to being in black-and-white to being color again.
Solution(s):
The turntable in CED players must spin at exactly 450 RPM for proper playback. The chrominance portion of the recovered video signal is most susceptible to loss if the speed varies, resulting in a loss of color in the video image. The F/G players derive their turntable speed from the AC line frequency and a ring of sixteen magnetic poles around the circumference of the turntable. A turntable speed check strobe can be used to verify proper speed. If the speed is off or varies there could be a number of causes:
A worn out turntable belt (obtain a replacement belt).
Excessive friction in the turntable or drive motor bearings (re-lubricate the bearings, ideally following the procedures in the service manual).
Belt uncentered on turntable drive motor pulley (adjust the motor mount screws so the belt rides centered following the procedure in the service manual).
Improper clearance between the turntable magnetic ring and the sync plates on the turntable drive motor (this requires RCA Synchronizer Plate Gauge #153308 to measure properly).
Weak magnetic field in the turntable magnetic ring (necessitating replacement of the turntable or rejuvenation of the 16-pole magnetic field, which is theoretically possible, though I've never attempted it).