Kristorial Posted February 28, 2015 Share Posted February 28, 2015 So I have just inherited from my grandmother an old Sears AM/FM Stereo 8 Track System with Record Changer Model No. 132.91751502 and its running a little too fast. On the 33 RPM setting its spinning at around 36 RPM and its significant enough to make Nat King Cole sound like someone is stepping on his balls. I heard you have to tweak the adjustment screws, but the owners manual doesn't go into that much detail. Can someone knowledgeable help me? Quote Link to comment Share on other sites More sharing options...
ajxd Posted February 28, 2015 Share Posted February 28, 2015 There will be two screws somewhere near the motor. Maybe from the top, back, or bottom. One is 45, one is 33. Should be marked. Adjust the screw to find accurate speed. Kristorial 1 Quote Link to comment Share on other sites More sharing options...
Kristorial Posted February 28, 2015 Author Share Posted February 28, 2015 Alright, I'll give that a shot tomorrow, I'm just kinda apprehensive about taking that apart. I'm a tank mech in the Marine Corps so I'm not very good at being gentle haha Quote Link to comment Share on other sites More sharing options...
Kristorial Posted February 28, 2015 Author Share Posted February 28, 2015 Alright so I popped it open and now I'm just trying to find the damn adjustment screws. Will post pics soon cause i have no idea where the damn things are. How do you post pictures on this site??? Quote Link to comment Share on other sites More sharing options...
aflycon Posted February 28, 2015 Share Posted February 28, 2015 Alright so I popped it open and now I'm just trying to find the damn adjustment screws. Will post pics soon cause i have no idea where the damn things are. How do you post pictures on this site??? You can use an image-hosting site like imgur and then paste the URL between tags in your post. Kristorial 1 Quote Link to comment Share on other sites More sharing options...
Kristorial Posted February 28, 2015 Author Share Posted February 28, 2015 If you need more clear pictures of any specific parts just let me know and ill take more. I just have no idea where to find the screws and ive been at it all day Quote Link to comment Share on other sites More sharing options...
allenh Posted March 1, 2015 Share Posted March 1, 2015 I don't think there are any speed adjustments in there, it looks like a standard AC synchronous motor that uses the mains frequency to keep speed. The motor power is the brown, grey and white wires going into the white plug on the TT so if there are any they will be at the source of these but I very much doubt it. It may be an idler wheel deck and if so it will be that the rubber idler is worn. If I'm right there will be a stepped wheel on the motor and when you change speed it moves the idler to run on a different step on the motor wheel. I would take the platter off and clean the idler and motor wheels but be careful with the rubber wheel and don't put anything on it that might attack the rubber, also check it is engaging properly when you change speed so a clean of that mechanism would go amiss. If it's a belt drive a worn belt usually makes them slip and go slower not faster and the idlers run faster because the wheel has effectively shrunk. Kristorial 1 Quote Link to comment Share on other sites More sharing options...
Kristorial Posted March 1, 2015 Author Share Posted March 1, 2015 Yeah i ended up taking the plate off and taking a look. It is an idler wheel with three different speed steppes on the motor spindle. I cleaned off the motor spindle and the rubber idler and that helped it a little bit. It wasn't quite there yet so i took a file, ran the motor, and ground the spindle down until it was registering at approximately 33 rpms. Judge me all you want, haha, but remember, if it's stupid, but it works, then it ain't stupid. Thanks for your help everybody! gabpower 1 Quote Link to comment Share on other sites More sharing options...
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