Replace electronic reverse with e-unit

Yes, you can do that. You will have to rewire the E-unit to work properly. You can use either AC or DC to energize the E-unit coil

Use the rectifier to apply DC to the outer/continuous bands on the drum and use the inner, switching contacts on the drum to apply switched/reversed DC to the motor.

30+ may be right for a 6amp reverse board, but your talking about the small Motors that are under the frame? Those boards are about 22.50.  but if you have an old e around yes you can use that.

What is that buzzing sound?

RoyBoy, I like your idea of using the rectifier before (instead of after) the e-unit.

Also, another question . . . .I have limited space in this Budd car.  Does an e-unit work sideways, or does it need to be upright?  It seems to me that gravity is needed for it to work.   Dave.

It needs gravity.

If your e-unit is PW you can sell it for more than a Lionel basic Electronic E-unit.   G

I noticed that most AF e-units sit sideways rather than vertical like the lionel units.  I don't have enough space for a vertical, but do have the space for the AF type.  The AF types go for $18 on ebay which includes the shipping.  An electronic unit from Lionel goes for $19, but then there is $9 shipping, bringing up to almost $30.

This is for the old K-line RDC commuter train set  (1 powered, 2 dummies).   Right now I inserted a bridge rectifier to get DC to the motors.  Runs great, but of course does not reverse or go in neutral.

Rectifier must be before the E-unit drum, or loco will not reverse.

I raise question of whether feeding DC to the solenoid coil would cause it to overheat.

Lionel did make a flat mounted spring loaded E-unit for a couple of engines. They might be hard to find but they did make them.

I can sell you a Lionel 103E shipped for $20.  A smaller Dallee Low amp one for $15 shipped.  If you need a good 6amp version I can sell you a Williams for $30 shipped.

While cheaper, I do have to believe your not going to like the modified Mechanical E conversion as much as back to an electronic one.  E-mail in profile,  G 

I was unhappy with performance of the spring-loaded E-unit on a 1946 #726, and replaced it with a QSI ACRU, which has been perfect.  They are no longer available unless you can find someone wanting to sell one they have squirreled away.

He needs a DC unit.  Lionel still has AC units (SSRU and even more modern ones) if you need one for a AC motor engine.  G