MY ZW WHISTLE CONTROL WONT WORK WITH FAST TRACK???????

First, check the "polarity" of the wires to the track. I presume you did check this as you stated switching wires.

I'd also suggest that you swap sides as well... so if using A-U, go try D-U (this is because the ZW actually has 2 rectifiers, one for each channel. It wouldn't be unheard of to have one go bad)

Additionally, the ZW whistle control has two positions... Most modern whistles only need the whistle switch to be activated part way.

I doubt it's the FasTrack. As mentioned above it's either the transformer, the wiring, or the locomotive. What's the transformer item number & the locomotive?

Old.transformers won't always make board triggered whistles blow, (and visa versa)

Adding a diode type button (can be made and can do bell too or be added for bell only) or swapping out the Lionel whistle disc fora heavy duty diode (good for most post war, but 99%  not 100%.

I.e. some whistles are just finicky (1 old and one new are finicky out of about 25 o mine)  

You mention bell. If you have a diode rated higher than a transformer amp output you can blow the whistle/bell with it strung from center to outer rail (hold with pliers, it will get hot, fast...the smaller amp the hotter....an 8a might work for a sec or two, but too much will cook it fast. This is for tests the whistle works at all)

The boards look more for wave shape than offset max is my guess (fast change). The electromechanical relay likes a heavy offset and doesn't care much about wave shape, it relies on the peaks more to do actual work.

The old whistles are on a 5v boost too. This is to make up for old whistle motor draw. New whistles use can motors or recorded sounds and don't need a boost to keep from slowing, so new transformers don't give a boost.

You can bypass the ZW boost or leave it when swappimg in a diode. (5v boosts can cause new locos to rocket ahead)

Building a box you can taylor boost as needed and include whistle and(or) bell

It just takes a handfull of diodes, and a button. Some extra switches for choice of wh/bell, and boost level (rotory or toggles) are optional.

Lol, usually bad track causes a whistle to blow accidentally.  A bad connection or dissimilar metal connection (in some old non-whistle transformers) can cause a temporary DC offset that triggers more wave sensitive whistles non stop (dc voltage does it too, but the loco will run on dc with a different tender(not for diesel, elect)

Got the horn to work on my diesel but the whistle will not work when engine is on track.

the tender whistle works great but not with the engine???

GG1GUYY

Has the whistle motor been serviced - cleaned, and lubed?

Are the tracks , wheels and roller pickups clean?  Especially important when the whistle operates with the tender stationery, but not when it is moving.

The transformer whistle rectifier may be old and in need of replacement even if it blows the diesel horn.

Larry

See the current thread "Blast from the Past" and look at the video. About half way through, there's an extensive "show and tell" by Jim Barrett in the Backshop, discussing the renovation of a ZW. He specifically shows steps for ZW parts replacement to improve the whistle function.

Does the whistle tender work for sure?  You haven't mentioned the type of engines (mod vs PW) .

Test ..mostly for POstwar, disconnect track power, reconnect -9v dc might do it, 12vdc should, up to about 20vdc max, should trigger the relay &run the whistle motor. 2- 6v lantern batt. in series = 12v, ( bat1+ to bat2- ; now use bat2+ for + and use bat1- for -)... 9v in series(18V) or parallel (+ to +, - to - =9v, slower drain (tests only)... a 12v car battery... or a DC power supply @ 2.5a min, hopefully 3-4a.

Running a train on dc makes the whistle or horn blow non-stop on pre/postwar and some modern ones. (I run a small loop off a car battery or battery charger by running a non whistle tender or hornless diesel; motors and e-unit don't care much and function normal (e-unit stands a slim chance at building magnetism; dissipates with ac use or running pawl thru a screwdriver demagnetizer)

This dc supply test trick may work on some modern Lionel boards too, but not all mfgs. No harm done to try, (ac contains both dc polarities naturally, doesn't always need both though). Modern andwill clang the bell if equipped depending on + or - dc wires go to center rail. PW does whistle/horn either way dc is wired to track)