COUPLERS OPEN UP FOR NO REASON

Hi here is one website on the forum , and I know there was a good one with Gunnerman about coupling and uncoupling problems and repair options too!

Alan

https://ogrforum.com/t...nel-coupler-problems

Welcome to the world of the big "claw couplers". Most work OK, some don't. Facts of life.

Well, aside from switching to Kadees, there are a couple of things you can try before replacing the couplers.

The "thumbtack" style couplers often uncouple due to the retaining pin not seating into the knuckle properly. This can be caused by a bad armature spring. Removing and adjusting the armature spring for more force (stretching it on modern couplers or bending it slightly upward for the older type). The other cause is a sticky opening in the knuckle which can be resolved by turning the car upside down, opening the coupler, putting a drop of light oil into the hole where the pin goes, then working the coupler a few times.

The newer "tackless" couplers are more involved as the hardware isn't readily accessiible. About the best shot there is to check the spring to make sure the shaft is coming all the way back into the coupler and lubricating the mechanicals.

Those are the quick and simple remedies. Hope this helps.

I've had a few 3-rail couplers open while running trains. Most of the time (99%) they are fine.

Are Kadees bullet proof?

I've lubed the linkage on the oversized couplers and that seems to help ones that stick or don't want to open. The thought of scale couplers has intrigued me though. With over 100 railroad cars that would be quite the project.

I've had two Kadee failures, both due to a missing knuckle spring on 804/805 series. The 700 series have internal springs, so that's a non-issue. I did witness failure related to an Intermountain reefer with a Kadee involving the Intermountain plastic draft box being snatched off (the coupler held fine; the box let go). Best guess is the glue/cement didnt hold the box on. So, I'd say they're pretty bullet-proof. Your locomotive(s) will start slipping before the couplers fail.

I'd recommend #700's (metal coupler/metal box) for non-metal cars and #745's (metal coupler/plastic box) for metallic cars. Use 743's (short metal coupler/short plastic box) for close-quarters installs (MTH 6-axle diesels and GP35 rear pilots) and 746 long-shank for passenger cars.

Some day I want to try the Kadees.However I will tell you just switching over to standard metal Lionel or MTH couplers is not going to solve the problem.I have had no choice but to wire strap at least half of mine shut to get them to hold in a 25 car coal drag.It totally wrecks switching operations. And don't even ask if you have many die cast hopper cars.Also many guys will recommend you keep the heavier cars to the front.I have had limited success with that .Nick

You will NOT have such "problems" with Kadee couplers. I began using the Kadee brand back in the middle 1950s, when I started modeling in HO Scale, and have never looked back.

Plastic couplers easy fix cut the pin holding the knuckle on from the bottom of the coupler remove pin . pull out the knuckle you will notice thin piece of plastic protruding from the inside of it that is the tension spring it is made of delrin plastic .heat a small pan of water to boiling and hold that piece in the water with needle nose pliers for a few minutes ,you will notice that spring expand in the hot water .take it out and let it cool them replace put in new pin and pean it . when you take the coupler apart gently remove the armature . i found this info in a mpc era greenberg repair maintenance book  work great teachman

My favorite is when a coupler opens without me noticing until the train comes back around and blasts the stalled cars.  This is even better when guests are visiting the layout! 

I just use rubber bands as I can then still reach over and push the tab to uncouple them.

If they are the plastic pull down ones I have had a lot of success just pulling the tabs out and switching them around. Also while they are off I put a slight bend in them it makes a tighter lock. On newer stuff my biggest problem is coupler heights not matching.

If you dont need them to function,can they be glued shut?

Dale H

When a $2000.00 Vision line Big Boy doesn't stay coupled to a 20 car train of $50.00, $60.00, and $75.00 freight cars unless a bunch of rubber bands are used to hold everything together there's a fundamental problem somewhere...

Jeff C

I agree Jeff, but the aggravation of dealing with OEMs is a higher evil. Lionel, MTH, Atlas, and the others must know about discrepant couplers because this subject has been vetted often enough. Yet the problem continues, so a fix is an appropriate action to take regardless of the price of the item. 

I have had some K-Line cars that the couplers kept opening on, I noticed the K-Line pin that holds the coupler closed is just a little shorter then the Lionel pin so I replaced one with a Lionel part and it worked great, no more opening.

Lee Fritz

Most of the time it is caused by the pin not riding high enough in the pocket and the slightest uneven track will drop it enough to separate.

When I come across this problem I use a simple trick. CA/super glue will keep it shut. You will not need to use a lot; a small amount will do it. You can undo the super/ CA glue by using either nail polish remover or a DE gluer made by the manufacture’s of CA glue. The down side of this is it will not open so I try and find some marker to identify it on the bottom of the coupler.

No stupid rubber bands or wires to look at.

MTC

John

A stupid question but where do you drop in the glue?

Dale H

I drop it on the pin, a little will also run down to the base tap which will also help it stay put.

I had to do it on the new Lionel CA halloween caboose, works good now.

I have some steep grades on my layout and have had to use a drop of hot glue on most of the couplers to prevent them from opening.  Hate to say it but the quality of what we are now seeing made 1000's of mile away is poor. At York I purhased a Legacy Reading Caboose. It was DOA.  Give me the old stuff!!!

Here is a post about fixing the Lionel couplers:

Fixing Lionel magnetic couplers so they stay closed

Search for  it with Google

In some cases I use rubber bands, other cases I use zip ties and in other cases I take apart or I add a little graphite.

Graphite works great. Simple fix.

Gentlemen,

    If I remember correctly, long ago Guns, Gunrunnerjohn started a thread showing how to fix this problem with the couplers, doing a file job on part of the knuckle.  You might want to both contact Guns, and do a search for the thread.  It was a pretty darn good fix it thread, however I do not remember the exact title of the thread.

PCRR/Dave

Is it possible to purchase a "dummy" coupler that is just a solid block of metal or plastic?  I'd like to solve the issue that way on my layout

The only "dummy" couplers I've seen are the ones that are included with MTH Premier steam locomotive models, and I believe Lionel offers the same item with their steam models. Those "dummy" couplers are for replacing the scale "dummy" coupler on the front of most steam models, thus the steam models can be doubleheaded. Those particular "dummy" couplers a quite short, as they are designed to fit into a steam model pilot assembly.

I have used Locktite blue threadlocker on a few couplers.  Must allow overnite curing but it does work.

The best things about using rubber bands to reinforce couplers that I didn't want to open - especially for loaded trains on grades - was it was a quick solution to apply to more than one van or truck and I could easily take them off.  

All of my problem couplers are glued shut since it is a very effective and a simple fix. I never use the opening feature anyways, so I could care less if they open and close. To glue them I just open the coupler, squeeze some glue toward the back of the open piece that is exposed when open and then close it and let dry.

BobbyOgauge shows a fix for "slamming" the couplers to get them to close that I have recommended for years - build up the "tongue" so that the incoming knuckle can push it all the way in.

Older thumbtack couplers can have their armatures bent slightly upward, with pliers, just a bit, to hold the pin higher.

Weaver plastic couplers are so bad (won't open far enough; won't close - could this even be called an "operating coupler"?) that I treat them like dummies.

Weaver die-cast are much better; not the best, but not bad.

Weaver used to sell plastic dummy couplers (the real dummies) that fit their trucks just as the "operating" ones do. I ordered a couple of dozen a few years ago; great for 3-railing 2-rail project cars with odd trucks. Just like the thumbtack couplers, but non-operating.

Weaver is, of course, no longer able to fill any orders. Sigh. Miss them a lot.

Kadees are not perfect, by a long shot. Personal experience in operating sessions on others' layouts. Kadees can be maddening, too.

However, they are less troublesome than the various brands (there's the clue as to what is largely wrong with O-gauge knuckle couplers - same design done to different levels of design standards and materials).

Suggestion: all the O-gauge "biggies" contract with Kadee to build their new trucks/couplers using their (Kadee's) coupler design, but to the traditional O-gauge knuckle coupler size. They would mate with Lionel (etc) so that the Good Ones could continue to be used. I find most to be "Good Ones".

Retrofit kits?

BTW, I believe that Kadee's #1 scale (1:32) couplers will mate with Lionel (etc) couplers...???

I think you're right. Where's Engineer Joe when you need him?

mikemike,

   Yes John's fix is kind of tedious, but it really does solve the problem. D500's fix works also, but you must be very careful using it, or you will damage your rolling stock.

The super glue does the job for quite a long time, however you no longer have an operating coupler, with this repair technique.  The rubber band and zip ties I am not fond of at all, but they do work, leaving the coupler completely en-operable also.

IMO the true fix has to leave the coupler operable, after all that is what I payed for when I purchased the rolling stock.

PCRR/Dave

I found some Weaver dummy couplers,

Dollar apiece plus shipping

clem k