Major failure on one of my locomotives

Miraculous find.....an MTH Parts diagram

https://mthtrains.com/sites/de...oded/30rtr13341e.pdf

Maybe this part? https://mthtrains.com/bi-0000034-0

I think your JB-Weld solution is probably as good as it gets.

That is the plastic motor mount which is good. What is broken is the actual gear housing. The screw holes for the motor mount crumbled. I checked as I thought I could drill straight through but that will not work. So if the J B Weld works then all is good. Not a big deal. I was thinking what might have put pressure on these mounts. I let my 3 year old run these trains. She has a habit of running it full power then hits the red reverse button at full speed. I don't know if this was the issue but it might be likely.

well if the casting was weak to start with and suddenly reversing may have caused it to fail. maybe better to save for parts for other engines !

Alan

I don't think throwing away the locomotive is the solution the OP is looking for.

Good fix! Can you resurrect the thread if 6 months from now it’s still going strong?

Thanks!

I'm going to let it set up for the next week. I don't think it takes that long for J B Weld but I thought it wouldn't hurt.

Then I will put it through a normal workout to see if it holds. I will update the thread after this then give another update after some extended use.

I will check the thread to see if anyone has any other ideas. For me this appears to be the best.

It's not an expensive locomotive and outdated but up to this point it has done it's job. I also figure I'm pushing the expected life of the PS 1 board. 

I should have taken some photos but didn't think of it at the time.

In the parts diagram, what is the number of the part that broke?

It would be the drive block #26.

If you could drill and tap the JB weld that would probably be a permanent fix. If you can’t perhaps backing the screw out before the weld totally sets up the threads may stay formed. I’ve never done this but it sounds possible. Good luck. 

The way to go is to coat the screw with wax before you cast the JB-Weld.  When it's all hard, you'll be able to remove the screw.  You can also tap JB-Weld, but you have to have the drill size correct to not put excessive pressure on the material when tapping it.

The drive block is $50, so that's an option if you fail with the JB-Weld.

I'd make the JB-Weld fairly thick at the screw location, as thick as practical.

gunrunnerjohn posted:

The way to go is to coat the screw with wax before you cast the JB-Weld.  When it's all hard, you'll be able to remove the screw.  You can also tap JB-Weld, but you have to have the drill size correct to not put excessive pressure on the material when tapping it.

I once bought a thread repair kit that resembled JBWeld. On an aluminum motorcycle rack I filled the hole with it and screwed the waxy coated screw in and waited until it cured to remove the screw. Worked perfectly.

GRJ, sounds like a winner to me. Good to know about the wax. 

You could also embed a threaded insert in the JB-Weld and have metal threads, another method.  Maybe just run the waxed screw onto a nut and bury the nut in the repair, when when you remove the screw, you have the nut buried in the JB-Weld and it will provide additional strength for the attachment after everything cures.

Another trick I use to contain JB-Weld is plain packing tape.  Turns out that JB-Weld won't stick at all to the adhesive on the tape, so you can build a shape with tape and fill it with JB-Weld.

Some really good creative advice here.  Many of the suggestions should work, as long as the root cause of the original failure wasn't zinc pest!  I would look over the rest of the drive block carefully for signs of corrosion or disintegration.  Because if it's crumbling you would be wasting your time!

I don’t know if this frame matches your loco.... but if it does?