Belated thanks to everyone. For some reason I'm no longer getting email notices when replies are posted (checked settings they look OK). Anyway, I have about 40/60 split between Kadee and older Horn Hook couplers. I have a couple of "transition" cars that can cross connect. Most of the issues were on older cars with Kadee... so I pulled the culprits, check with Kadee gauge and have replaced coupler, or else modified the height. As of now, the repeatedly troublesome cars seem to be working fine. I have seen some cases on these older cars that the coupler box can droop... that's a good sign for pulling the car and reviewing the whole undercarriage. But I think I'm on the mend here. Over time, I'll convert the worthwhile cars from HH to KD. But the transition cars are useful as a crutch and will likekly keep that around for some of the more stubborn conversions (a set of three 0-4-0 dockside switchers with HH couplers don't look like EZ conversions).
Hello, and to the Model Railroader forums.
Here is what I know:
1) You MUST have genuine Kadee couplers, period. Even the "clone" Walthers Proto-Max is not as good. Kadee is a gift to all model railroaders in that they have contiuously improved theoir product and maintain spectacular quality control.
2) "Standard Head" couplers are more reliable at staying coupled. Change out the #158s for #148s will help.
3) Vertical changes in trackwork are a problem. Check your track.
4) Make sure none of the knuckle springs (the coil spring on the outside) are missing. Kadee sells these seperate and inexpensive. I lose 50%- 75% of them when I try to install them. I just keep lots of extras on hand.
5) Kadee couplers work best in Kadee coupler boxes. Some OEM boxes allow too much movement up and down, and this can cause decoupling. 95% of my fleet has Kadee coupler boxes. Only some Tank Cars are the exception.
I hope some of this helps.
I hope to see you around in the forums once your moderation delays come to an end.
-Kevin
Living the dream.
If I park a train of say 30 cars on a down grade for a couple of weeks or more, when I start it off, as soon as it hits the flat the train starts to come uncoupled in multiple locations. I have mostly KDs and as soon as I couple them up again all is well. It does not happen if the train is parked going uphill with no slack in the couplers, only when they have been bunched up for an extended period.
.
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
Hello All,
John-NYBWIf you have a large layout, consider buying bulk packs because they are cheaper. I think they come in 25 or 50 pair packs.
Even if you don't have a large fleet the bulk packs will save you money in the short term and headache in the long term.
I have found that it is always handy to have some spares on hand for that odd moment when a coupler or it's spring(s) "disappear" or when you get that new piece of rolling stock/locomotive that needs a coupler upgrade.
Hope this helps.
"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"
I have a few 158's in the mix, and as these are smaller (closer to real scale) sized heads, they are a little more "temperamental" with trackwork flaws. (My polite friendly term for some malfunctioning equipment.)I have not had the experience of them disliking the larger sized 5/148 couplers however.
When I have this occurring frequently on a section of trackage, there is almost always some trackage issue, dip/bump/hump style, or alignment issue, including one rail lower/higher than the other, missing rail joiner, etc... creating the issue. (And almost exclusively occurs with the "scale head" couplers, unless it's really bad.)
Is anything sitting too high with the trackwork? The OP mentioned at turnouts, maybe a higher than it should be frog or guard rail?
Only time I've had 5's do it is when I lose a knuckle spring, or have a low hanging glad hand. I have had the "clones" of the plastic variety do this for no apparent reason, so the plastic clones get pulled and replaced with real metal ones.
Ricky W.
HO scale Proto-freelancer.
My Railroad rules:
1: It's my railroad, my rules.
2: It's for having fun and enjoyment.
3: Any objections, consult above rules.
I have fixed some coupler problems by putting a drop of CRC 2-26 on the coupler head. Sometimes the coupler closes, but not all the way. The lube helps this problem, especially on older couplers.
I'll second the suggestion to replace the coupler with new KDs. Since the KD clones came on the market, I have yet to find one that operate as reliably as the originals. I'm snooty when it comes to couplers and I don't put any rolling stock on the layout without replacing whatever couplers they came with. I used the #5s for years but have switched to whisker couplers (#148) for new installs. Both operate reliably. As long as I have the height correct, the center spring (#5 only) is in good shape, and the knuckle springs are on properly, I've never had a problem with them. If you have a large layout, consider buying bulk packs because they are cheaper. I think they come in 25 or 50 pair packs.
First thing I would do is reinspect my cars with a NMRA wheel gauge and a KD coupler and trip pin height gauge and make adjustments and replace any missing knuckle springs.
A slight dip in the track should be be the cause of cars uncoupling if the coupler and trip pin are the correct height.
Also #5s and #158s do not play well together due to the size diffence and will uncouple. KD #5s and #148s will work together.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
I'm not modeling in HO but in N scale and use exclusively Kadee/MT couplers.
The seaks are the same I think
It seems I have had same trouble like you with some of my N scale cars and with Micro Trains couplers
They uncouple or couple not well, and some uncouple here and there without any good mechanic answer
First all the clones which appeared in HO and in N scale when Kadee patends were over, work not reliabily with the Kadee/MT couplers, especialy in N scale, they even not work well together, they are clones, they are silmilar but not Kadee or MT coupler for sure; so they are prohibited on my fleet and anyway a standard couplers is the best way to go to avoid any trouble in operation.
Second, some of my cars were not used for a while and stored in their box; part of my car fleet never had the chance to roll on my layout for different reasons.
They were out of use for a long period, severals years in fact.
Now they are all on the layout and here come some troubles
Some knuckle didn't open and some other stay open and close not well, they need a real schock to be closed or to be in the proper position.
These MT couplers work with a small spring enclosed in the coupler box
I have also checked height and the pin form and all were in perfect gauge by MT standards.
But just a puff of Greasem ( graphite powder) in the box and on the sliding parts of the coupler was the answer to make them working properly.
Friend of me who works in injection parts of plastic and zamac ones tell me they use kind of oil in the molds; all the plastic parts like the zamac ones are covered with these lubrifiant used to release the molds.
It seems, but not clear, this oil in time begun to be like a glue on which some part can be "glued" or just keep a bit, but this could be enough to keep the small parts of our couplers in a bad order.
Yes may be the best way is to clean parts in a solvent, but I didn't, I just use the Greasem and all work fine; all the couplers which gift troubles, treated this way works like new ones, none has given troubles anymore.
I'm not sure it's an answer to your problems but this is an easy try and quick try.
This was my answer of my MT couplers troubles.
Some of the plastic KD clones have shanks that can bend enough under strain to cause a mismatch in height leading to a separation.
cowman You said you were using #5's and #158's. 158's are scale couplers and I think I have seen that some people have had a problem with the scale couplers staying connected to "regular" couplers. I don't have any #158's, so maybe somebody that has both can relate their experiences.
You said you were using #5's and #158's. 158's are scale couplers and I think I have seen that some people have had a problem with the scale couplers staying connected to "regular" couplers. I don't have any #158's, so maybe somebody that has both can relate their experiences.
Whenever I have operated on a layout where #158s are used along side #5s, the 5s always preform better, with the #158s always being slightly more prone to uncoupling or haveing little issues, but I don't think this is the only source of the OP's problems, as 158s still are comparible with 5s and work fine a majority of the time.
I would immediately expect there to be issues with coupler height, but as the OP has checked that and reported no issues, and has no grades, it must be something else.
I am inclined to believe that the issue is with bad springs (or no springs) keeping the couplers closed (not the centering spring, the other one). Some plastic couplers don't even have springs on them, just plastic ten thing that do absolutely nothing! I recommend you check for good springs!
Regards, Isaac
I model my railroad and you model yours! I model my way and you model yours!
mbinsewiAlso, check the couple(r) [SIC] swing on your loco, and on the cars.
If nothing else is awry I agree with checking the coupler swing.
When the couplers are too tight they bind and can cause derailments.
If you are running tight curves; 18- or 15-inch curves in HO, if the couplers aren't long enough the corners of cars and/or locomotives might touch causing derailments too.
Longer shank couplers could help alleviate this if this is the problem.
Nine times out of ten when it happens to me I find the spring on the coupler has gone AWOL.
Are the couplers opening up or just seperating?
Good luck,
Richard
Are you sure there are no elevation changes? Even little bitty tiny ones? Miniscule invisible humps or sags?
Any difference between forward and reverse?
Have you tried running the trains through the trouble spots at double extra super slow speed to look for any uplifting or dipping? Riding up on the frog or something? Unwanted superelevation on the curves?
Any jerking or porpoising of the tractive effort that might cause slackening of the tension of the coupler? Any hidden magnet that might open the clasp?
It kinda sounds like the horizontal swing of one or the other coupler shanks might be restricted.
LINK to SNSR Blog
If most of your couplers work fine, just replace the bad ones with new Kadees. It's not worth trying to diagnose the problem, because that will be the required fix anyway. Sometimes I just put Kadees on brand new equipment if it's equipped with junk.
It takes an iron man to play with a toy iron horse.
Yeah, search on this site is worthless. Has been so for years. Google works, so does Duck Duck Go. Sounds like you have the coupler height issue under control. Are the centering springs working properly? Are we talking truck mount or body mount? Are we talk real Kadees or Kadee clones? Are the knuckle springs present for duty and working? There was a line cheap Kadee clones with the knuckle spring a mere plastic finger that broke off easily. For couplers with a knuckle coild spring I use a tiny (very tiny) dab of Duco cement on the ends to keep it in place. When I have a troublesome car I replace what ever it has for couplers with genuine Kadee couplers. Forty and fifty foot freight cars work better with body mount couplers. Long cars, 80 foot passenger and so, need truck mount couplers to get around 22 inch curves let alone 18 inch curves.
David Starr www.newsnorthwoods.blogspot.com
When I unpacked my trains after 20+ years, the box spring for the #5 couplers had lost its mojo and would not center the coupler. I suppose the spring on the knuckle could weaken too, but mine prefer to vanish before that happens.
I don't know when Kadee look alikes started to appear, but nobody loves those.
Henry
COB Potomac & Northern
Shenandoah Valley
The Search the Community thing hasn't worked in a long time....waiting on promised "up-grades".
Maybe check the coupler pins and see if any are hitting the rails. Just before I install new couplers, I bend that pin up just a tad, to make sure they clear everything.
Also, check the couple swing on your loco, and on the cars.
Mike.
My You Tube
Can't get the search to return ANYTHING on ANYTHING using the box on the right (even "DCC" returns no hits).... Anyway, I've got some really old rolling stock and a couple of cars are decoupling when the locomotive hits a turn of needs to pull thru a turnout. All knuckle couplers (but some of unknown age). Could they just be "weak" (due to age)? I have checked and rechecked coupler heights, they all look good vs Kadee gauge, as well as adjoining cars. I'm planning to do some more coupler conversions anyway (lots of hooked horns around), so I'll have a supply of #5 or #158's hanging around. There are no elevation changes on this layout. Any other places to look?