Weaver Engine eliminating the drive shafts between trucks.

Have you given any thought to Northwest Short Line's Stanton Drives?

I have used a couple of them on HO motive power.  The first of which was repowering a Hallmark Gas Electric (Doodlebug)...which was incredibly successful.  Reminded me of the adage 'Turning a sow's ear into a silk purse!'

Don't know what your specific Weaver loco candidates are, but using a Stanton Drive on each truck would give you two motors for power, and NO gear train headaches.  No interior intrusion...a boon to detailing, speaker, decoder, additional weight for traction, etc..  Well worth the price...IMHO, of course.

Very responsive folks to communicate/discuss your project with.  Another treasured state-side manufacturer in this hobby trying to relieve 'headaches'!

Just a thought and a recommendation...FWIW.

KD

Trying to keep my costs down. Not worth the $ to do several engines with all with those drives. The other issue is the motor in those Stanton drives is rather small, the motors in the Weaver are significantly more robust.

I have a fleet of weaver single motor drive locos, A couple of FAs and a bunch of RS3s.      I noticed a lot of failures early on .    However, as the years have gone by, it seems there are less and less failures.    This is just sort of observation no real statistics, but perhaps hope.

I think converting the loco to only one powered truck will reduce the pulling power by more than half.    I have had a few of the All Nation NW2 switchers over the years that only had one powered truck.    They were very weak pullers in my experience.    Adding more weight did not help.   If anything it reduced the pulling power because it also added weight to the dummy truck which the powered truck had to pull. 

The gears are only a few bucks a piece.

If you’re going to dummy a truck, you’ll want to remove the gears from the axles so that the dummy truck rolls freely.  Otherwise you’ll waste power trying to drive the geared wheelsets, or they may just end up sliding down the track instead.

@prrjim posted:

I think converting the loco to only one powered truck will reduce the pulling power by more than half.    I have had a few of the All Nation NW2 switchers over the years that only had one powered truck.    They were very weak pullers in my experience.  

I agree, the examples of locomotives with a single powered truck I've encountered and owned were anemic pullers.  In one such example, I had the Lionel Phantom set from 2000, it had trouble on Atlas track pulling it's four cars!  I added a second powered truck, and it's a totally different locomotive now!

Improving the Lionel Phantom Locomotive

Split chain gears was a common problem with Weaver engines. P&D had their own gears  made, We changed out every engine before it was sent to the customer.