# Santa Fe 8352 engine slips



## Mr D (Feb 17, 2018)

Hi all, new to the forum and to model trains, please bare with me as I am not sure of the correct train talk.

I bought a used Santa Fe 8352 Diesel Engine, which was not working. I took apart and cleaned the motor and armature. I was able to clean the copper armature, brushes, and e unit and I was able to get it to move and fire the lights up. However, the vertical engine on forward will only drive 12-14 inches and the motor seems to pop out of gear and revs on high without the train moving anymore. It seems a little better in reverse however does the same after a loop around the track. This is also without pulling any cars. 

It seems as if the worm gear is popping out of gear. The power truck is stamped "8250-125".

I noticed that the plastic gear that the drive shaft is attached to also slips and has fallen out. I have pushed this back on.

The worm wheel and worm axle is not locked in, the worm wheel spins freely, it seems like it needs a locking mechanism?

I tried screwing down the set drew on the plastic brush plate but this did not work. There is no other washers or bearings to adjust or replace.

Any ideas?
Can I rebuild this unit or just look for a new/used power truck to replace this one.

I tried attaching pics but do not know how to upload on this site.

Thanks for any information.


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## T-Man (May 16, 2008)

MPC era is not noted for quality.


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## CTValleyRR (Jul 26, 2014)

I would just replace the gearing. Northwest Short Line has a ton of replacement parts for work like this, and a lot of on-line how-to guides. It would help to know the manufacturer of the original, too.


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## T-Man (May 16, 2008)

There is no part breakdown of the motor. The best bet is replace it all. That is one reason why you see the motors on ebay. Your armature is good and this is the common part that sees failure. Normally one of the plates come loose.

A worm gear sits center on an axle where it is spleened.

If it spins that is not good.

The link to the diagram is on page 1-24

Lionel does not support parts for this era but with a little determination you may find a part on a modern version. 
For this the simplest part would be a new motor.


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## Mr D (Feb 17, 2018)

Thank you all for your replies. It seems that I may fix this situation with a new drive gear (Lionel 600-111B Brass Drive Gear) 

When I receive the new metal drive gear. Can I just press it onto the worm axle with a pair of needle nose pliers and a flathead screwdriver or do I have to dismantle the truck and use a special press? How does the drive gear stay put?

I'm trying to do this with out filing off the pressings that secure the truck from the sheetmetal.


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