mollieelle

I got it!! That did it. Some fishing line, pb blaster, cleaning, and loosening the small gear only. I can properly time my machine now. Thanks for the early Christmas present all. Wohooo!

Thanks so much @CowboyBob I'm cleaning them up and will give that a go. To make sure I'm after the right thing - below is a photo. The smaller vertical gear is connected to my hook shaft. When the screws are loosened on that gear the hook shaft should rotate freely without turning that small gear - correct? So that should really be the only gear I need to loosen to free the shaft to rotate independently?

Thanks so much @trash treasure and @Scoutmom103 I’ll work today to de grease those gears and free them. Probably a good thing to do anyway. Ive read the service manual for the 591, the 191s contemporary counterpart carefully and I am positive the hook itself is not timed correctly according to the timing requirements of the machine. @jimi Unfortunately adjusting the needle bar alone is not enough to remedy the situation. The hook and needle bar each have timing requirements they have to meet. Changing the needle bar to meet the hooks out of time position is not fixing this timing issue. The needle bar needs to be at a specific place in its path (2mm from bdc in this case) to have time to form a loop that the hook can catch properly. I can change the height of the needle bar to meet the hook, however, the hook then meets the needle a hair after bdc (bottom dead center) which does not give it time to form a loop. The hook then barely catches the loop sometimes, slices and splits the thread sometimes because the loop is tiny and too tight to catch, or misses it altogether sometimes.

@trash treasure I too share your suspicions that the gears are indeed just stuck. They just must be I’ve loosened every other screw I could find to try. But afraid to go prying the gears loose unless I know that for sure - though it may come to that. This machine is an odd subclass of the pfaff 191. So it does vary a bit from the general 191 schematic.

@trash treasure That's exactly what I thought would do it but no such luck. It definitely seems there's a sneaky screw or novel mechanism that im missing.

@Constabulary Thanks so much. Is it an operators/instruction manual or a service manual? Unfortunately the operators/instruction manuals do not have the info I need. The hook is not meeting the needle at the correct time. The hook needs to be rotated in the post to time it to meet the needle correctly. There are generally a set of screws that need to be loosened in order to allow the hook shaft to rotate independently. I’ve loosened the screws I know to, however, the hook shaft is not free to rotate. So I’m missing a screw or a step to free thehook shaft to rotate. Your machine could well be quite similar and if you had a service/adjustment manual that would be super useful

Thanks @Michiel That is my usual strategy as well. I’ve read the Adler 68 manual and watched a video of that machine being serviced and timed by @Uwe. I’ve also read every pfaff post bed service manual. While they are close, there seems to be a critical screw that requires loosening on my machine that I am not finding by puzzling. With the screws loose I can see to loosen from the cumulative manuals, the hook is still not free to rotate.

Thanks @trash treasure That is, however, the instruction or operating manual. Which does not include any information about timing the machine unfortunately. I would need what is called the service or adjustment manual. Which I have scoured for and cannot find.

Hi all. I have a new to me Pfaff 191-5 in the shop that needs timing and was wondering if anyone has experience timing this machine? I cannot locate a service manual for it and am having trouble identifying the screws to free the hook to rotate. I’ve compared to post bed manuals I can find with no luck. Any help is much appreciated.