DC problems with 2-8-4 and 4-8-4

[uncbob]

 I am running two ovals--18" and 22" with DC



I have 2 MRC Sound and Power 7000 supplies



I can switch the  supplies between the ovals

In addition to other manufactuer steamers I have Bachmann  2-8-0  2-8-4  4-8-2  4-8-4

All Bachmann are DCC equipped and I have inserted the jumpers  to bypass the DCC

The 2-8-0 and 4-8-2 and all my non Bachmann have no problems with either supply

The 4-8-4  and 2-8-4 will only run in reverse on supply A  --they run OK on supply B



Any ideas ?

[uncbob]

Found the problem

I did not use the jumpers on the 2-8-4and 4-8-4

Evidently the decoders in these 2 didn't like one of the MRC 7000 supplies
Why I don't know --Popped the jumpers in and problem solved