Lionel AF Sd70 electro coupler.

Thanks John.

The "O" Gauge guys have more experience with this than we do. You might look for discussions of similar problems in the "O" forum, or in the TMCC/Legacy forum.

Here's one thread that might be worth a read:

https://ogrforum.com/t...66#18605835807329166

Also, a similar question was posed in an earlier issue of CTT:

http://cs.trains.com/ctt/f/95/p/32801/421110.aspx

And, if there's any question about your power source, a quick view of the wave form discussion (which addresses electro coupler operation) might be of value:

http://www.youtube.com/watch?v=OMR25JoCZiU

Good luck with your problem. Be sure to post any resolution so the rest of us can leverage off of your pain.

Craig,

Thank you for the info. I'll dig into it some more. I wonder if anybody else has a problem uncoupling with the flyer electro couplers?

Just my opinion here, but this isn't an electrical issue to me. I have an SD70ACe, + the scale Mikado and two scale Pacifics + one U33C of "Modern" vintage. None of these couplers open as far as A. C. Gilbert production couplers; i.e. the knuckle travel arc is smaller than Postwar Gilbert's. 

This really should be addressed by Lionel as the locomotive and rolling stock couplers are all afflicted with this issue -again "in my opinion".

Shoot mine don't even open.  I am using DCC so either I dont have the function/CV program correctly or they are inoperable.  When programming mine, the rear one got really hot. I actually unplugged it.  

In time I will probably just pull them off and put Kadee 802s on them.

A word of warning for you MSTJ Ham; I elected to install Kadees on my SD70ACe, when I went to remove the electro-couplers, I found I could not get the front one to budge. Yes, I do have the correct screwdriver head for these screws, but to date I have not been able to budge the screw without worrying about buggering up the screw-head completely. At least I was able to remove the rear one which allows operation with my rolling stock.

For some reason, the Chinese insist on installing some screws at 400 foot #s of torque or using thread locker where it is not needed or using the wrong type for the intended application. I wish Lionel would address that issue as well.

Lionel always recommends puffing some dry graphite into the coupler mechanism and on the knuckle hinge. Don't know if it helps.

It could be paint or minor fitment issues with the knuckle or the locking armature.

banjoflyer is on to some solutions.

It may be a simple fix. if you are moving the engine away at 1mph restricted speed, like a real train has to do, it may be enough when you fire the coupler to separate. It needs room to swing. Opposite of moving in to force it to close, pull it open.

Thank you for the insight D&H...for now I am will leave them be.

Thank you all. I ordered two new couplers from Lionel and I'm going to try to file them like banjoflyer suggested. I have had the sd70 over a year, so I'm not worried about the warranty. I will post if this works or doesn't. 

Thanks again,

Mike

Hello,

I followed banjoflyer's suggestion and filed the coupler. I used a small file and took off about a 1/32 to a 1/16 off of the operating part of coupler. I did a little at a time and tested. The coupler works as good as my o gauge couplers. I'm so happy with it now. i'm using american models freight cars. I noticed the couplers on these cars are not as open as american flyer cars. I used some needle nose pliers and opened them a little. I can uncouple one car anywhere on the layout now, even on the fly. All I will say is, be really careful with the couplers. They are not very forgiving. If you put to much force on them they will break. I'm not going to pay for your couplers, LOL. I might start selling my o gauge trains now and buy more s. Thank you all for your suggestions.

Happy Holidays,

Mike