What Kind Of Oil To Lubricate MTH Smoke Unit Fan Shaft?

It should work fine, personally I use 102 on all of my o guage moving parts including the fan bushings.

It works great on axle bushings, steamer rods etc.

Its a "heavier" light oil that stays where its put ( less inclined to run off) and lasts longer. Any fan I've ever oiled with 102 has never needed it again.

DON'T DO IT!!!! The can motor will fail (arcing internally) when lubricant or smoke fluid gets into it. I learned this the hard way. If my warning is too late, you can buy a new motor from GGG.

I've oiled a number of motors, none have ever exploded.  Sometimes the oil doesn't do the job and the bearing noise is still there, but that's a different issue.

John,

What is that different issue and what is the fix for that different issue?

Thanks,

Hugh, the "different issue" is that the oil doesn't fix it.  That is normally most likely the bearing hole has worn to the point where oil isn't enough to solve the problem.  I replace those motors.  However, a good many have worked for some time with just oil. 

I agree with john, a very small amount of Castrol GTX 5w20 on the shaft won't hurt and might help. 

The key is a drop and to manually work it in or let it soak.  Normally oilite bearing are impregnated with oil and it comes out under heat and goes back into the bearing via capillary action when cool.

Too much oil and too much smoke fluid which overflows and gets into the can motor can short it.  Shorted fan motors lead to shorted audio amps on PS-2 3V board.  G

Wow GGG,

That is really an interesting connection. Most of the smoke units that I have worked on have too little absorbent packing in them which allows too much smoke fluid to slosh around. I can see how when handling and rotating these locos that excess fluid can get into there. My method of repair pack lots of wool insulation so hopefully that does not happen.

I will watch closely if  get in any more bad audio amps.

I usually fill smoke units while shell is still off when I do repairs.  You can see sometimes the fluid wick across the bottom of the PCB (top of the smoke unit) which places it near the air port.  Making sure the wick is suppressed at the air port so that no fluid can transfer into the air chamber is important.

Usually when I have found shorted fan motors the air chamber and the motor are slippery with smoke fluid.  I have to clean out the air chamber before installing new motor.   G