Dempster 12A 8ft Rebuild

[vollek]

To All,

Thank you for allowing me into your forum.

I need help with a Dempster 12A 8ft motor rebuild. (First time at trying this)

I have most of the motor disassembled except for the main shaft.

Motor Mostly Disassembled.jpg

The main shaft feels like it is stuck from sliding out (it does turn).

I completely removed the pin (the picture below shows the pin I'm talking about, blue arrow) but that didn't seem to help.

The main shaft Castle Nut to the left is unscrewed as far as I can get it, it's hitting the side of the outside surround.

The main shaft won't move in or out at all.

Pin.jpg

On the front of the Shaft there are two items that I'm not sure what they do, and if they need to be removed to help the main shaft slide through.

See Yellow Solid Arrow and Red Dashed Arrow.

Main Shaft Front View.jpg

Here are some closeups

Yellow Arrow.jpg

Red Arrow.jpg

View into Shaft.jpg

Thanks for any help you may give me, I definitely appreciate your help!!!

Thanks
Kevin

[windybob]

Well you sure picked a good one to start with . LOL These can be a bit difficult. The pin (blue arrow) has nothing to do with the shaft coming out. either drive it back, or cut it off for now. Red dotted arrow, is a brake shoe spring holder. Means nothing for now. The two pinion gears need to be loose on the mainshaft. They have keys under them. They must slide on the shaft for shaft removal. The front of the snout is the trick. Let me edit a picture, and I will show you what needs removed. Give me a bit to do it.

[windybob]

Oh...the yellow arrow, YES that must at least be scewed out 1/2 inch, better if it's out all the way.

[windybob]

This ring must come out. Most likely you have the felt oil seal, so this ring is a spacer. It should b e a split ring. Behind it is the outer bearing race. If you do NOT have the felt oil seal, then this could be the race. never the less, it has to come out. The setscrew under the snout keeps the out bearing race from coming out, that's why the setscrew must be mostly, or totally removed. So, take out the ring, and the bearing race. Only thing keeping the mainshaft from coming out now are the two pinions. That is why they must slide on / off the shaft.

Dempster 12-A ed.jpg

[Windcatcher530 Dan]

Kevin welcome to the forum. You have the expert on Dempster's helping you, when it comes to those mills never worked on one. That might be a good thing !!

[vollek]

windybob and Windcatcher530 Dan,

Thanks for your replys, windybob I'll work on that ring, and the bearing race.

I'll report back to you on my progress.

Thanks again for your help!

Kevin

[vollek]

Just to add to the discussion, here is some history of this Dempster.

Unfortunately, the Windmill was not maintained for at least the last 20 years.

We just recently bought the property the Windmill is on.

The tail spring was broken, the pitman arms were both broken, and all the gears were heavily worn.

Here are some more pictures of the Dempster as I'm taking it apart.

Before.jpg

Plate in front of Main Shaft.jpg

I'm a little worried why the hole on the Main Shaft's front plate is worn oval (not round)...

Warped hole.jpg

If you all see something that screams "not worth repairing" please let me know.

Thanks
Kevin

[CTXmiller]

Welcome to the forum.

[mtblah]

Kevin , welcome aboard , the guys who have responded to your inquiries are all correct ! When I started on my Dempster’s I asked the same questions .
Ended all the pain ! Just cut the shaft off !!! You will end up replacing just like all the other worn parts .
And the others are right as always. , stick with Aermotor
Do as I say , not as I do . Now have an open gear Flint & Walling with WOODEN bearings , you may get hooked like some of us who started with one w/m
Mike B
New Braunfels TX

[mtblah]

Kevin , when you get ready for parts contract Slade Litsch in Thomas Oklahoma , Windy also has a LARGE selection!