Pfaff Hobbymatic Sewing Machine Stuck Reverse Fabric or won't feed

Pfaff Hobbymatic Sewing Machine Stuck Reverse or Won't feed fabric

I have repaired a couple of Pfaff Hobbymatic walking foot electronic machines, either fabric wouldn't feed, or they are stuck in reverse, because they couldn't hold the presser foot down, so it couldn't feed properly. 
 
It was caused by the dried up lubricant, which locks pieces together, like the presser foot spring. It can't push the foot down against the feed dogs, when the spring is glued in place, so the stitches pile up in one spot.

The reverse issue, was due to the stitch length & reverse lever, on the same bushing, same glued lubricant issue, EASY fixes! (Please remember, I am NOT an expert, & I don't always know the correct terminology, so I will do my best to explain how I fixed this machine. 
If your machine is a Pfaff, this may be another part of the problem. Underneath many of the 1980s to 2000 Pfaff Sewing Machines, like my Pfaff 939 Hobbymatic, there is a metal pivoting rod, around which, the plastic & pvc parts which control stitch length & reverse, are supposed to pivot. Over time, particularly if exposed to much heat & humidity, a tiny bit of oil either works its way out of the materials themselves, or migrates to the area, & dries to a sticky resin, gluing them firmly to the pivot rod.
To check if this is the problem, all you have to do, is remove the bottom of the machine, & under the motor, in the "pillar" of the machine, you will see the tiny black set screw, which holds the rod in place. If you loosen the set screw at all, the rod suddenly begins to pivot, allowing the lever which controls reverse, & stitch length, to pivot the rod, so it seems to fix the problem.

It is not fixed, but you have located the exact spot which needs cleaned! If you just loosen the set screw, over time, the rod will work out of the machine frame, & could damage the machine, so you can't just loosen the set screw.

You have to disengage the lower piece of the reverse spring, from the bottom of the white plastic piece (reverse gear mechanism) it is hooked to,  2/3 down the left side of the photo below. The yellow plastic part, that I am pointing at, with the red screwdriver, is part of the lever system for the stitch length control, & the reverse lever. They actually work together, but because the "permanent lubricant" dried to a glue, they were literally glued to the rod they were supposed to pivot on. 

In the photo below, note the screwdriver tip coming from the bottom left of the photo, is pointing to the C clip on the left end of the rod, which must be removed, to be able to remove these parts, to clean them.

 In the next photo, the screwdriver point is pointing to another C clip which must be removed

after you remove the C clips on the rod, & the set screw far enough, that you can remove the plastic pieces from the rod completely.

The rod can stay in the machine frame, you can use a Qtip with alcohol, to clean the resin off the rod, push it back & forth through the frame if necessary, to get to all of it.

Use another Qtip dipped in alcohol to clean inside the tube area of the 2 pivoting plastic parts, & when they are clean, replace them on the rod, & make sure they pivot freely, before putting everything back together. If they pivot completely freely, go ahead & replace everything back in the machine, making sure you get the gears back in the correct positions, & the "finger" that sets into the helical groove in the plastic wheel, which controls the stitch length & the reverse lever. Once you are sure everything is properly aligned, replace the C clips on the pivot bar, tighten the set screw, then reattach the lower section of the spring, on the white plastic piece that controls reverse & stitch length. Sorry, I don t know better technical terms, but that s the basic reason these great machines get stuck in reverse! Do NOT lubricate this area! That will cause the same exact problem, when it dries up! Happy Sewing!

Becky