help needed - repair on MTH 6 wheel pass car truck

Do these have a thumb tack? If so you can remove the armature (piece that the thumbtack is attached to) and bend it up. This makes sure the pin that holds the coupler closed has max pressure on it.

Pete

thumbtack ?  No.  An armature between the wheels gets pulled down by magnetism.  The other one offers more resistance if I pull it down with a fingernail.  

I wish to correctly repair it as i do wish to do switching with it   (part of a passenger train that might pick it up or drop it off).

Put that in the middle of the consist and glue it shut.

does the photo help things any?

I repaired one of those once. It must be one of most expensive couplers to make ever. I think I counted 18 individual parts go into that. The problem is the tab at the end of the arm is prevented from going all the way into the coupler knuckle and what is preventing it is within the truck under (looking upsidedown as in your picture) the plate that gets pulled by the magnet. I had to disassemble to whole truck to get to the problem and file some metal away so the arm could move further into the knuckle. If you want to investigate first remove the truck and move the plate and the tab behind the coupler head to see whats preventing full movement. I don't know of a simple repair here.

Pete

hi pete

thanks much!!   This is most helpful . . . means I can fix it myself with attention to detail and care.

I agree  . . must have been a gawdawful expensive item!

John

it appears, on close inspection, that the coupler head is held on by a Phillips screw.

I am hoping if I remove it then I can get to the  circular spring, stretch it out a little and make it a tad stiffer.   And not have any part fly off  

You don't have to diaassemble it.  The tab on the plate that is pulled down by the magnetic track section is exerting too much pressure on the mechanism that slides into the coupler.  When you go around turns, the slack is less causing the coupler to open.  If you can hold the plate securely to the truck with your fingers, then bend the tab so it doesn't put as much pressure on the mechanism, it will work better.  Done a few at MTH, but it is a pain.