medion Report post Posted October 25, 2018 Hi all, I have a Pfaff 335 - the older style, image attached as an example. I'm having an issue which appears to be getting worse, whereby the motor is hard to turn/sticks. It's not the machine, if I take the belt off the machine itself turns over smoothly. That being said, the clutch/motor still works perfectly fine, and you wouldn't notice it if you didn't hand crank the needle into position or around tight spots. I'm just wondering if this is normal behaviour/the motor is wearing out/bearings are toast/or other. Am I not doing something maintenance-wise? My other two machines are much newer with servo motors so I have nothing to compare - I also live in a remote place without access to industrial machine mechanics. Any help greatly appreciated! Cheers! Quote Share this post Link to post Share on other sites
Mark842 Report post Posted October 25, 2018 My understanding of how clutch motors work... When on the motor is spinning full speed all the time. When your not pressing the pedal your clutch motor is in the braked position with the clutch pads separated and either a piece of rubber or leather engaging the pulley keeping it from spinning. I believe your motor is working as it should. You should be able to put slight pressure on the treadle pedal that will release the brake and still not enough to engage the clutch. This should allow you to turn the machine by hand. I'm not positive about this but I think you should be able to do this with no power applied to the motor, just press the pedal lightly and try turning the machine. I'm sure others will correct me on the parts I got wrong. Been a long time since I used a clutch motor Quote Share this post Link to post Share on other sites
brmax Report post Posted October 25, 2018 My understanding also. good day Floyd Quote Share this post Link to post Share on other sites
Matt S Report post Posted October 25, 2018 I have a clutch motor on my skiver. There is, as others have mentioned, a brake which impinges on the output pulley when the pedal is fully released but releases with just a light touch on the pedal. @medion if you switch the motor off and press the pedal a little, does the "stiffness" disappear? Quote Share this post Link to post Share on other sites
medion Report post Posted October 25, 2018 THANK YOU everyone - you're all right, it is the clutch being in brake mode when the machine is stopped. If I run the pedal very lightly, the stiffness disappears - thanks so much, I was getting all worried about having to fit a new motor or something Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted October 25, 2018 3 hours ago, medion said: THANK YOU everyone - you're all right, it is the clutch being in brake mode when the machine is stopped. If I run the pedal very lightly, the stiffness disappears - thanks so much, I was getting all worried about having to fit a new motor or something I bet you didn't know that there is an adjustment for the brake on the right end of the motor. There is a big hex head bolt in front of the output shaft that screws into the housing. You can loosen the locknut, then turn the bolt in or out to adjust the amount of slack the pedal has before the brake lets go and the clutch engages. In order to get the most range of pedal throw, tighten up the spring loaded thumbnut on the right end of the activating lever under the motor. If the spring action is backed off the lever will hang lower and won't have much movement before the clutch activates. Quote Share this post Link to post Share on other sites
