MDC Box Cab Deisels & Climax Locos

[Trussrod]

This was originally writen in answer to another former fourm member but contains a lot of useful information uf your having problems with yours running right?

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I have an MDC track cleaner that runs flawlessly for me and has for years with just the standard motor and gearing and does not run jerky, as you mentioned in a much earlier post, that your climax was doing. It runs with smooth steady power for me.


Now, contrarly the MDC Climax I picked up in kit form last year does run jerlky as well as having trouble negotiating various areas and turns if they're just slightly too tight.

I corrected the limited truck pivoting problem by using a fine round jewelers file and releived the outer edge of the journal connectors where the truck drive conector hits when the truck is pivoted completely to one side or the other. This made a big difference in a smother running mechanism in tight curves.

Also, ensure that the copper wipers are pressing against the contact screw heads firmly enough and that the wipers are also pushing against the insides of the drive wheels for good pickup.

Thats the only thing I did check last night as I was having problems with the Climax running without sometimes stalling on a 20" radius curve. As soon as I gave it a slight adjustment sidways off she went so I now realize it must be poor electrical pickup of the wheel wipers and I had just securely soldered feeder wires to the track almost right at the stall point too.

I'm going to ensure the truck wheel wipers are making good contact and I'll bet that will solve the problem. I usually bend the wheel wipers in a semi curve on the end to contact the inside of the wheels.

Also be sure to put a rounded bend on the end of the poortioin of the wiper that contacts the screw heads so they don't come in contact with the frame and short out.

HTH

 

[Trussrod]

I found out a couple of more things about these loco's.

First, is that you can't tighten the Bull Gear Drive assembly to tightly to the frame or it binds against the gear on the Armature shaft of the motor making itr extremely hard to even turn the Armature! The Bull gear housing mounting assembly could use a shim of about .005 between it and the frame of the loco.

Second, the trucks, 'Do Not' have the electrical pickups that rub against the backs of the drive wheels as I thought they did.

 

[CNR Glen]

I converted one of those to a belt drive by turning the bull gear on a lathe to make a pulley. I added a can motor out of a DVD player with the second pulley. The unit moves considerably quieter now. I'll try to find some pics for you.

 

[CNR Glen]

Here's the pictures of my project.

I cut the shoulders off the frame to I could lower the boiler up front. The motor is isolated on an aluminum block so I could DCC it if I wanted.

 

[Trussrod]

Hi Glen,
Sorry for the delay in replying back to you.

You went through quite a bit of work alright and yours is weathered nicely and sure looks
well used. I was a little too timid to go too far all at once, although I do plan to weather
mine too as they look too new at present.

My excuse is that the cab suffered major damage from a smaller tree falling on it and had to be rebuilt, so hence the fresh paint job.

I have more to do on it and one of the main things is to add about a .005/.010 shim under bull gear housing mounting brackets to move the Bull gear a little farther away from the drive gear on the motor.

I also want to paint the boards an apropriate wood shade as well as the frame and end beams which will probably wind up a dull or greyish red.

I also may remove the simulated grab rods on the cab as one is partially missing anyway.


Here are my two shots.

 

[CNR Glen]

I have more to do on it and one of the main things is to add about a .005/.010 shim under bull gear housing mounting brackets to move the Bull gear a little farther away from the drive gear on the motor.

Instead of shimming the bull gear why don't you shim the motor? Shimming the bull gear will drop it and it's housing lower and it might interfeir with trackwork at turnouts.
Another thing I did was to take each truck apart and carefully inspect all gears for flash. I also had to ac some gears onto the axles because they were loose and spinning. I used my Dremel witha brass wire brush to polish the worms on the driveshafts as well.


I have alot of leftover parts here so If you need anything just ask.

 

[Trussrod]

Hi Glen,
That a thought about the Bull gear dropping lower but I doubt that even .010ths is going to make that much difference, in fact I checked and there is plenty of room under the BG housing.

I redid my photos so they are lighter & sharper so take a look again. I'm not sure how you got yours to turn out so much bigger though unless it's just me that can't see them enlarged?

Thanks for the offer of extra parts but I'm fine. Does yours run smooth without jerking? Mine seems to be getting better but still has a ways to go and I think the shimm should help a lot, I see and let you know.


Take care, it good talking with you,

 

[CNR Glen]

The other thing about dropping the gearbox is it will put the bull gear and universal shafts out of alignment with the truck drive shafts. This could increase drag on the drivetrain and also increase noise, much like going around a tight corner increases noise.

Mine ran pretty good before I converted it to belt drive but it runs even better now. I actually have enough parts to build 2-3 more climaxes but since I went DCC I don't have much use for them.