Alco pa

Are you sure the B unit is powered?  MTH 20-20310 from 2014, PS3, both A units powered, dummy B, single stipe "prospector" scheme, tethered.

the B is powered the A unit cab number is 6001

Premier or RailKing?  Paint scheme?  Weathered?

it is black top yellow sides single black stripe and silver around bottom cab number 6001 . It is mth premiere

That's the "prospector single stripe" scheme.  Originally bought to power the California Zephyr.  Went through various paint schemes during its lifespan.  MTH's website lists multiple sets (ABA) but all are both A's powered, B dummy.  I'll keep researching.

Is it ABA?  Tethered?  B unit cab number?  Second A cab number?

it is A B their is a tether and plug between the A and B but no tether at the other end of the B unit the frame at one end underneath is marked MTH Trains

if you send me an email address, I could send pictures to you

In my profile.  Please call

Sounds like somebody switched shells and discarded the middle unit.

that could be sent pix to your email address. see what you think

Go to MTH website and use your RR and cab number in search.

tried that, no results was the answer thanks

Roger

Figures, would have been too easy.

@roger smith posted:

tried that, no results was the answer thanks

Roger

Cab numbers or pics?

I'm leaning towards an uncataloged item.  Check underneath for a battery charger receptacle.  If round, early PS2, (5 volt) ,if rectangular, PS2, (3 volt).  Can anybody else help?

their is no charger plug on the bottom. supposed to be PS3

Just checking

It's my understanding PS3 engines have capacitors - not batteries, so if you remove the shell and do not see any batteries (or a 'Battery Component Replacement' - aka BCR) presumably it would be a PS3 engine.

the A unit has a pair of 2.4 volt batteries in blue plastic shrink wrap standing  at the back

According to my sources that is a 3 volt PS 2 unit.