Actually to have a bit of fun, it like buying a 20 year old car, and putting a 20 year old motor in it... finding a new gear would give you detective of the year status!   

Even if you found one used, the worm gear (the other gear is just called a worm) would most likely be damaged or in poof condition...

sorry, best bet is new chassis... look on my page, that large worm gear is awful... see the pictures with the pliers

https://www.elmassian.com/index.php/large-scale-train-main-page/motive-power-mods-aamp-tips/bachmann-motive-power/big-hauler

Greg

interesting, when was this purchased, as they have been out of stock for some time...

did it really come with DCC? or is it "DCC ready"??

look inside and see what is plugged into the socket, I think it is NOT DCC...

Greg

Yeah an interesting area of packaging design... now involved in passively cooled 10 gigabit switches, and those lasers in the fiber optic transceivers are tough to cool!

fans are easy when you start to conductively cool stuff never designed for that method of cooling.

(the video does not show the "secret sauce" of cooling)

https://www.youtube.com/watch?v=5zXA1bh4dLI

Actually, direction does matter... in some use cases...

so sucking in air is preferred, because if the smoke unit is used and you have the fan "exhausting" people have reported it pulls the smoke into the loco, not out the stack.

other than that then normal electronic cooling rules are in order, and then you should be exhausting air, but the difference here is small.

if you look at modern electronics, a fan mounted to the case will be exhausting, pulling hot air out along with any heat from the fan itself... but in this case the fan's heat is minimal..

But, in the very specific case of this loco, the most important thing is as wraujr stated (sort of) just a bit of airflow over the "hot" device makes the most difference..

Spent a number of years with real products (a small company called Hewlett Packard) in the 70's when we really started looking at what the heck the fan was doing...

so, will you use smoke? then the choice is easy..

Should be no issue, I see that the motor is geared to both axles in each truck.

You should be able to get the PDF files of the exploded diagrams here, if not email me.

Greg

Fan helps, you just are not hot enough yet! 

https://elmassian.com/index.php/large-scale-train-main-page/motive-power-mods-aamp-tips/bachmann-motive-power/45-tonner

The fan was there to cool the electronics, per Bachmann... but sometimes it is installed backwards and blows in a direction that does not help cooling.

Most people toss it.

will a human answer the phone in the parts department?

unfortunately, the "DC dummy board" has a number of components to control the lights, and no circuit diagram is available as far as I know.

1. I would go to a large G scale forum like MLS and ask there.
2. you could buy an adapter plug from Bachmann and do some wiring to make the lights work...

I do not know for sure, but I believe the flicker electronics just need to be powered,

Did you look to see if they have them on the store.

check ebay, the only indicator unless you want to track other auctions..

(TRAINZ.com will indicate last selling price)

did you check first to see if the wiring diagrams are on the Bachmann site?

umm... 26 years of experience with Bachmann?     

unfortunately, many bachmann gears split, the white "nylon" ones.

The most requested repair part.

no delrin... never stock on any bachmann.