New MTH 20-3619 Aux Water Tender

You perhaps ought to have checked your J's tender for the necessary plug in pigtail before assuming compatibility. Regardless, depending on how handy you are, I believe there is an adapter harness to convert your tender over so the rear coupler will work. Not sure what other features your aux water tender has. If it has sound etc, there may not be any practical way to convert it, but MTH should have the answer for  you.

Rod

Rob, I have the Imperial J from around 2006 (#608) and IIRC, it came with a tether inside the tender shell. It is specifically for attaching to an auxiliary tender although the one available at the time was the 30-???? 027 version. Not sure which engines came equipped this way but might be worth a look.

According to the MTH website, this tender is specific to a PS3 J engines.  As I just bought a railking 30-xxxx N&W J engine I am unsure if this tender would work with Railking engine, besides the fact that this auxiliary tender is full scale Premier and works on O-42 or greater curves.  So hope some one else has this tender and can answer questions.

I did buy a auxiliary Premier tender at York just to have it realizing size differences.  But now curious why the 20-3619 is noted as for PS3 J only.  Maybe has LEDs rather than incandescent lights like older models?

The 20-3619 Aux Tender is sold to work only with Premier engines. The Railking Engines are not wired to have the wire harness to hook it up. The Premier J also has a switch that you flip which cuts off power to the main tenders back up light and coupler and sends it through the harness to the Aux tenders back up light and coupler. The reason the manual says it's for PS3 only is because the back up light on the Aux Tender is an LED and only PS3 boards can control LED lights. Your best bet would be to find an MTH tech who knows how the engines are wired and could splice a harness in for you. Other wise you will simply just be pulling it around. 

Thanks John.  Pretty much assumed what you said but just curious if I was correct.  But I could be wrong, but never have been wrong about anything before!! 

The aux tender I did buy had a tether assembly in box and with instructions I see what they are doing.  So if I had access to MTH schematics as far as what PS3 board connectors did what, and converted the aux incandescent to LED I could do conversion.  Since I don't use couplers I could probably just splice into J tender lamp circuit and run wires to aux tender.  Probably PS3 couplers are electrically different than PS1 or 2 couplers (current draw) so would not modify. 

More trouble than worth conversion.  Besides almost every time I have opened an engine or diesel shell for yearly lubrication, no matter how careful I re assemble I cross my fingers there is no poof or magic smoke (seems MTH packs 15 pound of wiring inside a 5 pound shell, so many chances for pinched, cut, or grounded wires).  I will just drag aux around with backup light always on and say engineer forgot to switch it off after last reverse move.

And finally, hope everyone had a safe and happy Thanksgiving.

No problem! Sounds like the Aux Tender you bought is an older version. The ones released around 1997-1998 did come with a kit to splice in the tender for the Protosound 1 engines. To my knowledge they have not offered such a product for Protosound 3. If you were to attempt it, you would need an LED bulb, and most likely a new coupler. I spoke to MTH a while back and the Proto 2 and Proto 3 couplers are the same. Only change was when they went from Proto 1 to Proto 2. 

Happy Thanksgiving to you too. 

Things evol over time, but there are RK Engines with tenders designed to work with AUX tenders.  Newer models have the harness inside the tender as mentioned early.  You unfold it.  Some have switches to control which couplers fire, other have been set up to have the front coupler fire the AUX tender, so read your engine manual.

Tips: Early PS-1 Aux tenders use 1.5V Bulbs and PS-1 couplers.  They will not work with PS-2 or 3 engines with out changing both.  Later PS-2 tenders have 6V bulbs and PS-2/3 Couplers. Couplers work with PS-3 but not the bulb.  Latest versions are PS-3, again couplers work but wired for LED.  So if you are trying to get a new PS-3 Aux tender to work with PS-2 you need to modify wiring to support bulb.  Coupler will work.   G

Thanks, I printed your message and put with my stuff for reference.