[JMedwick]

I have tried so many things and this engine still runs really slow. Cleaned top to bottom. Tested with another tender. Swapped out the chassis. Swapped out the armature. Swapped out the plastic holder for the armature. Tried different spacers. Tested with and without the smoke unit. The armature still turns slowly when I spin it by hand, like something in the assembly is causing the sluggishness. My only other guess is to now swap fields.

 

[alaft61ri]

Did you ck your quartering ck linkages if u can send pics. When turning by hand is the shell off that why I said ck linkages. Before u put housing on armature does it move freely..
Al

 

[T-Man]

Does it run right on the bench? Strip it down. Shell, tender, smoke, and rods. Check soldering and run it. Look for smooth running drive wheels. Check for bad axles and Rims touching the frame. Clean the worm drive with a wire brush till it shines. Check the brush length too and spring tension. Get it to work on the bench first.
Running slow is only bad when the motor gets hot. It means it is fighting something. Pay attention to heat. A sLow would not bother me but a hot motor would.

 

[mopac]

Remove all side rods. Motor just turning rear driver. What do you notice.
Disconnect smoke unit rod. You have done most of what I would do. Different
tender with same results tells you it is problem with the engine. Does it run slow
in forwards and reverse? Have you tried new brushes and springs? Have you refaced
the armature? Have you cleaned the grooves between armature segments? I have a
northern that runs fine in forward but slow in reverse. I believe the problem is a wire
to the engine plug. Has your engine ever run right? Keep trying different things till
you find the problem. Good luck.

Smoke fluid can gum things up. Ask flyernut.
Try with just one thrust washer on each end of armature.
Look for dry grease on axle gear and screw gear on end of armature.
Oil axles where they go through bearings.
Let us know how you fixed it. When you get it.

 

[JMedwick]

I did check the quartering too, turning the armature by hand and then running with no linkages and then one on each side. No change in performance. I think the next step is to totally swap out the field coil.

 

[JMedwick]

It does not run hot, more so running slow. It ran the best on the bench without the smoke unit attached. I am inclined to revisit that part. I really have to crank it up on the transformer to make it run when fully assembled.

 

[alaft61ri]

I know how u feel recently bought a dieselfew weeks back cheap I like u all most sold it as parts did get it running took two weeks. Good luck you will get it.

 

[flyernut]

It does not run hot, more so running slow. It ran the best on the bench without the smoke unit attached. I am inclined to revisit that part. I really have to crank it up on the transformer to make it run when fully assembled.

That tells me it's either mechanical or electrical..Polish the linkage on the smoke unit, and make sure it is smooth and running free. Make sure the smoke gear is free. Check your wiring for any frayed or loose solder connections. I had a Northern that simply would not smoke as much as I wanted. I gave up on it.. During a rainstorm, I pulled it off the shelf and took it apart, and found a wire that was only connected by 1 strand. Problem solved.If and when you change the field, try turning it 180 degrees, that sometimes work. Make sure the armature is of the correct length, and the brush bracket assembly is the correct one for the armature.

 

[JMedwick]

Went back at this engine today and now it is running. The new armature and armature holder helped some. Fixing the solder connections from the tender to the engine even more. Looking good and smokes well now.

 

[alaft61ri]

That looks really nice like new.

 

[JMedwick]

It’s in good shape and is actually part of a full 4611 set.