Adler 67-GK373 or not?

[GaryCotnam]

Hi from Canada. This is my first post on this exceptional site and I'd like to see if anyone can help me restore my old Adler 67-GK373 to reliable operation. First off, I bought this as a refurbished machine way back in 2009 from a large dealer in Montreal.

Although I had no sewing experience, I wanted primarily to make tarps for myself but also desired to have a machine that could sew leather straps for camping bags in the future. The Adler manufacturer reputation, the model 67 specs and price seemed right for me so I followed the dealer's advice and bought  it. At first it sewed ok but not perfectly; there always seemed to be some minor glitch which was disturbing but that I accepted for my own use. These were problems like skipped stitches which increased so much in reverse operation that i stopped using that feature. I made several tarps each with it's own set of flaws and sometimes I'd try "to really solve the problem this time" but never did. I downloaded several Adler 67 Operation, Service and Parts manuals, studied them and fooled with various settings and needles and have ended up with the current situation where it now won't sew at all. I've just replaced the hook and bobbin cover assembly (Hirose components), feed dog and needle plate (China) and added some missing(?) but "Genuine Adler" parts to the upper thread tension system. I've discovered that I cannot be at all certain I actually have an Adler 67-GK373; even though labelled on the front as a "Chandler", it has an escutcheon plate on the back that says Adler 67-GK373 and an obscure number on the inside of the main casting that I labouriously decoded as "067 140131", which or may not be the serial number. According to specs the 67-GK373 has needle system 134-35 but came with DPx17 (135x17, SY3355) needles; I currently have Organ needle DPx35R, size 20 PD installed and loaded with Bonded Polyester Left-Twist size 138 upper thread  and same thread but size 92 in the bobbin. Due to file size constraint, I've only attached four pictures but I have several others if I can get them to upload.

The following 2 pictures illustrate the unacceptable type of stitches I'm now getting.

Top of material: brown thread is 138 bonded polyester upper, gray thread is 92 bonded polyester in bobbin; sewing started at "S" and finished at "F":

:

Bottom of material:

This photo shows what it used to do!  

Gary

Any assistance will be greatly appreciated!

Gary

Edited August 23, 2021 by GaryCotnam
Spelling mistakes!

[kgg]

3 hours ago, GaryCotnam said:

Any assistance will be greatly appreciated!

My suggestions would be:

1) If the machine came with 135 x17 did you make the necessary adjustments to allow you to change back too the original 134 needles. If not I would use what the machine came with or make the necessary adjustments.

2) Using a #20 needle in my opinion is too small for V138 thread and the loop that the hook catches may not be formed properly so you get skipped stitches.

3) Use either V138 thread or V92 thread for both top and bobbin thread until you figure out where the problem is then venture into mixing thread sizes. I would suggest starting with V92 top and in the bobbin.

4) For tarp type sewing getting the knot to be pulled up you will need multiple layers, I would probably try folding the tarp up until you get a 1/4" of material and see what happens. A quick test would be try a say three or four layers of denim material and see what it does, I know my Juki 1541 S hates thin stuff so I use another machine to cover off thin stuff.

5) The rat nest on the bottom indicates to me too low a top tension which maybe caused by top the routing. If I see correctly, you have the top thread going straight through the bottom hole of the top thread pin. I suggest you try going into the top hole half wrap around the the pin and out the third hole. The more holes used will also increase the top thread tension.

6) The amount of bobbin thread tension and the direction the bobbin spins off thread should be rechecked.

7) A couple of closeups of how you have threaded through the top thread tensions may also help.

8) I would suggest taking a look at the video

Just some things to try,

kgg

[GaryCotnam]

kgg: Thanks so much for the quick and comprehensive answer to my multi-faceted problems. There is so much history on this machine to relate since I've owned it from 2009 to the present and lots I've forgotten. All of your comments are much appreciated. I'll do my best to respond to each point in turn. My current thinking is that the basic problem is in the tension system but I'm also trying to be methodical and rule out any other factors, such as verification of my actual machine type, needle system, needle/thread size and type, etc.

I've seen opinions from some knowledgeable people having experience with the older German machines that indicates some of these industrial machines have been "dressed up" to look like superior models, presumably  for financial gain... I don't really think that is the case here but I also don't rule it out. So that issue is probably a red-herring... I've even questioned whether my thread is Left or Right Twist and am now quite sure but not 100% yet that it is standard Left Twist..

Now to your comments:

1) As I recall, when I picked up the machine in Montreal it came with one package of 10 Ruitai DPx17 Size 110/18 needles, 1 installed in the machine and no thread, which  was no problem since I  had spools of bonded polyester in sizes 92, 138 and 207 on order from The Thread Exchange. While I was there I bought a box of 100 Riutai DPx17 needles in size 125/20, expecting to use it with the 138 size thread. Shortly afterwards, I also ordered boxes of 100 Riutta DPx17 needles in Size 100/16 and 100 Flying Tiger DPx17 needles in Size 180/24 from the Montreal dealer, who simply fulfilled my order without comment. Obviously, I didn't know what I was doing since the 100/16s are too small and the 180/24s are too large for the Adler 67-GK373. That's when I started learning about needle systems, sizes  and matching needle to  thread type and size, I think I had moderate success with 138 on top and 92 in bobbin but am not certain about that point. I don't recall precisely but see that I have Organ DPX35R needles in sizes 125/20, 130/21, 140/22 and 180/24 in stock so believe I bought these several years ago in the hope that their quality is superior to the Riutia brand..

2) I certainly won't argue with experience but my choice of 125/20 needle for 138 bonded polyester came from interpretation of the service manual specs which shows needle size ranging from 120 to 150 and synthetic yarns sizes from 60/3 to 20/3 for the Adler 67-GK373... however, I could easily have misinterpreted these different systems. so trying 130/21 with 138 bonded polyester is definitely worth a try.

3) Yes, the smaller 92 thread might make troubleshooting easier so that is also worth a try. Thanks for these suggestions!

4) I never thought of quadrupling the material; maybe the test job at double thickness (or should I say double thinness?) is simply too easy for the way the machine is currently set up!

5) I'm pretty sure I've got the thread routed according to the general Adler 67  instructions but perhaps the GK373 version needs even more tension from the thread spool. Very hard to see in the full picture but the routing from the big thread spool is through the two spool support loops and then around the front of the guide pin then front to rear on the bottom hole, then rear to front on the 2nd from bottom hole, then into the tension mechanism. It is my current belief that the tension mechanism is the root cause of my problems. I've completely disassembled this mechanism, including the mounting plate and found the felt washer on the right tension assembly to be worn, so bought a new one (part no: 0016004010 ; labelled "Felted Washer Durkopp 167"). While the mechanism was apart, I cleaned gunk off all metal parts with fine steel wool and all feels quite smooth and clean now. The left mechanism (with the take up spring and thread pulley) seemed to be missing a back plate so I ordered part no. 3671100350 ; labelled "Washer Durkopp 267 Adler". Presumably these parts also fit the Adler 67! At any rate these two washers are now installed but I'm not sure I've got the left tension parts assembled correctly because the thread pulley does not rotate freely unless the retaining nut is almost off, so I'd like to verify this assembly detail. The old Adler manual pictures I've got are even worse for this detail than the ones I've been able to upload for all to see. I'll try to send a close-up to see what you think. Shouldn't the left tension mechanism thread pulley freely rotate at all times?

6) I believe I've got this correct: when I hold the open part of the bobbin cover facing me with the ear up and on the right side and then insert the bobbin, the thread is going upwards on the left side, then through the slot and under the tension spring which is u-shaped at the front, so the thread remains in the middle of the u but under the spring. When installed in the machine the bobbin rotates counter-clockwise as it releases thread. Does this seem right to you?

7) I'll try to send as much detail as the forum will allow. Note: hook assembly & bobbin cover are brand new Hirose components; still using old feed dog and needle plate since new plate is not quite same width as old one and didn't work any better but it is standing by in reserve if needed.

8) I did watch the video (although it is a large bobbin 167-GK373). I'd be so happy to have my machine running like that one! Gary  

 

[GaryCotnam]

kgg: I now realize that there was at least one key point you raised that I failed to answer in my previous post, namely how I set up the machine for the  Organ DPx35R needle, size 20 PD. As mentioned earlier, I have several different sizes of this currently preferred needle and some of the packages list the DPX35R along with other designations (134-35R, 2134-35R, DPx35R,  SY7225,) which I assumed means they are equivalents but maybe that is a false assumption to make? The Adler 67 Service Manual indicates that the 67-GK373 uses needle system 134-35, whatever that really means is unknown to me. The dealer supplied Ruitai  DP x 17 (135 x 17, SY3355) needles; is this contradictory to the 134-35 spec? Anyways, I'm aware that needle & hook timing must be carefully done and have done that with the Organ DPx35R Size 20 PD needle installed following the directions provided by the excellent YouTube video by Uwe Grosse https://www.youtube.com/watch?v=pL9WiZeKZAY.

One other idea which has come to me, since mulling over your very appropriate comment "rat nest" concerns winding bobbins. I know from my fishing reel experiences that there is a way line happily winds and another which is a constant struggle to work. .I've found this is usually caused by line twist, so to fix that I let out the entire spool at a fast trolling speed with nothing attached at the end and then wind it back. Usually once or twice per season is all that's needed. Anyways, is it possible my bobbin winder is twisting the thread the wrong way while filling bobbins? Another thing I haven't mentioned is that my top thread now often shows signs of fraying, which i think is an indication of something hampering the thread path. Even with the tension release lever depressed pulling the needle thread is hard to start and sometimes jerky, which I think is caused by the spring pulley not smoothly rotating. What do you think?

Please note that I added the washer against the plate on the left tension spring/pulley assembly because a parts diagram for the Adler 67 I had downloaded showed its existence... that part was either missing or not used for the 67-GK373. Maybe this washer is just complicating the tension process.

These are my Organ and Ruitai needles; are they interchangeable or incompatible with my 67-GK373?

Sorry for the overload of detail; my thinking is that better too much than too little but I also know that it can be annoying to cull out the important info from the fluff.

Gary

[GaryCotnam]

kgg: Doh! I'm suffering from a self-inflicted wound! I took out the "missing" washer from the left tension spring/pulley assembly and now the machine will sew stitches!

They were pretty sad ones on the first try but at least I got about 20 done without "rat nesting" (except at the end). I increased top tension and that eliminated all but tension was still not balanced so every trial after that was an improvement. Pretty basis stuff but thanks for your support which helped me just knowing someone was interested!

 

My stitches are admittedly no hell yet but at least I'm now moving in the right direction and can sew! It's so hard to get good technical information; in fact, that's what drew me down this rabbit-hole in the first place because I thought my tension system was missing parts. The March 8, 1982 "Spare Parts" by Kochs Adler AG for several models of the Adler 67, specifically depicts washer 367 11 035 0 in diagram 1 as applicable to the 67-GK373 model as well as to several other 67 models. But hey, I don't think brand new machines provide anywhere as much technical info as these old timers did!

Thanks again, Gary.