How do I fix a spring on an MTH Coupler with hidden uncoupling tabs?

A little update, I got the coupler disassembled. Now, I don't know if this problem is caused by the spring or the pin.

Which spring are you trying to service?....take a picture with a pencil or something pointing at the spring you want to fix.....there’s a coupler spring in the knuckle, and there’s a centering spring for the arm........Pat

I will need a jug of JackD to tackle that. 

The centering spring is always fun to get lined up, that's where the JD come in.

Since we're on the subject- My MTH Railking coal car couplers are intermittently coming apart.  My coupler doesn't look like the one above. I do have a spring I can see ( visible in picture) is this the only spring or is there one inside the knuckle I need to replace. If so there isn't enough JD in the world for me to work on it because I have essential tremors but I have a friend who I can call upon to work on it.

What exactly is "coming apart" on the coupler?  A picture of that would be useful.

John, I decided to try something simple first. I was able to loosen the screw holding the silver spring. I stretched the spring a little and re-installed it. I ran it for 20 minutes and had no problem. I also had to do this to a brand new Premier coal car. I'm just glad there wasn't anything smaller than that spring & screw.

Don

gunrunnerjohn posted:

What exactly is "coming apart" on the coupler?  A picture of that would be useful.

Here are some pictures of me pointing to each item:

Spring:

Pin:

Well, it's tricky getting that centering spring in.  You have to first stick it in the cavity and catch the ends on the lips, then drop the coupler on the pin without disturbing it.

I don't understand the issue with the long spring, those are simple to put on.

Peter, I wasn't very clear on my description of my problem. The moving "flipper" ( I don't know the exact name for the part) on the knuckle of the coupler would just open up and leave a string of cars sitting on the track. No parts were "coming apart". Neither one of the springs in your picture look like the spring I stretched to get my couplers working again. The spring in the photo I attached was only about 3/8" long. I just stretched it out then reassembled it and it seems to be doing fine.

Thanks, Don

The spring inside the coupler can be bad, those can be replaced, but you have to remove the rivet.  The coupler spring it TC-22, the rivets are TC-23X for the black ones and TC-23 for the chrome ones.

I'm thinking about replacing both the spring and the pin.

Well, if you are replacing the spring, you typically have to replace the rivet as you have to cut it off to get it out.  I keep both in stock as this is a pretty common issue.

Right now, I have the truck completely disassembled, and ordered 10 new centering springs. The only other question I have is: What does the rivet look like on this coupler?

Knuckle rivets all look the same, the only difference is some are chrome and some are black.  That's the only rivet you should encounter there.

Home stretch: got the coupler and spring altogether. Now only one piece left before putting the body screws back on. Does anyone know what piece is in the second image and where it goes?

Just figured out what that black piece was. It was part of the inside of the coupler and I put it with the long spring, and reassembled it. It took a few disassembles of the truck side frames to keep it from getting jammed. I have yet to test it. Now I'm off to do the baggage car.

UPDATE: The coach car test run was a success. Will do the baggage car tomorrow night. After that, I'll fix the trucks on my MTH PRR Observation car.

@Trestleman1 posted:

Peter, I wasn't very clear on my description of my problem. The moving "flipper" ( I don't know the exact name for the part) on the knuckle of the coupler would just open up and leave a string of cars sitting on the track. No parts were "coming apart". Neither one of the springs in your picture look like the spring I stretched to get my couplers working again. The spring in the photo I attached was only about 3/8" long. I just stretched it out then reassembled it and it seems to be doing fine.

Thanks, Don

Does anyone know the part number of the "flipper" on the knuckle of the coupler? I have a couple of broken ones I need to replace.