power feed LT40

[head block]

My power feed jerks sometime have to turn power switch wide open to get it to move.

[Tom]

It's either the rheostat (speed switch), frozen cam followers (wheels the head rolls on), loose belt, bad bearings on the shaft that has the pulley (sheave) that the belt rides on , or  just some sawdust or a stick stuck  on the chain that the sprocket uses to pull the head.  Sometimes a chip will get down there and get wedged in. 

[Bibbyman]

Check for obstructions, etc.  Check rails to see if they need some oil and cleaned.  Check chain also.  Check the cog that pulls against the dive chain. Check drive belt tension and condition.  Check head cam rollers to see if they have seized up. 

One time I had a log roll back against the backside of the mill and bumped the drive belt cover.  It didn't take much to pull it back out but I didn't notice that the pulley under it was also bent.  Every revelation it would bind up and the head would slow down.  I took me a while to figure that out out.

[head block]

does the drum switch control the feed speed? If so could it need some help?

[pineywoods]

Tom and Bibby pretty well covered it but I'll add one more. On my mill it turned out to be a corroded splice in the wire between the control box and the drive motor. If you make a habit of using the fwd switch as a throttle, garanteed you will sooner or later have some burned contacts on the drum switch.

[DR Buck]

The drum switch shouldn't have any effect on feed speed.  If it's not something mechanical like listed above it could be the speed rheostat.  I just replaced mine.   It had a 'dead' spot and the head would jerk forward if I set it at that spot.   I took it apart twice and cleaned the carbon track.  This kept me going for about 6 months until I finally got the time to put in a new one.  

[Chuck White]

does the drum switch control the feed speed? If so could it need some help?

No, the drum switch doesn't control speed.

The speed is controlled by the speed rheostat.

- - - - - -

I had problems with my FIL's LT40 Manual one time, I couldn't get the head to move forward, but it would move in reverse.
I disconnected the battery and then took off the cover on the control box and bent (put a little more tension on) the fingers of the feed drum switch.  It doesn't take much, just so they make a little better contact.  With age and use, the fingers will lose their tension, and not make good contact with the multiple points.  While you're in there, put a little drum switch grease on the contacts.  They're supposed to be greased every 50 hours.

[Chico]

Be sure and use dialectic grease if you grease the contacts themselves . I 'm not that familiar  with these systems but I'm assuming they can be rebuilt like all other drum switches though silver solder may cost more than a new switch .
Chico

[Magic Smoke]

Depending on what year mill you have, it is very possible that there is a light labeled "In" on the Power Feed Module that will indicate the signal coming from the potentiometer (feed rate switch).
You may want to remove the P/F belt to make this test easier but just watch the light as you have the drum switch in the forward position and while moving the potentiometer up and down. The light should track the movement of the potentiometer smoothly, if it goes out in certain spots or is irradic, replace the potentiometer. Here is a link to Wood-Mizer's troubleshooting guide that better illustates this, as well as other possiblities.

http://www.woodmizer.com/manuals/sawmill/troubleshooting/electrical/super%20power%20feed%20checks.htm

[Chuck White]

Once you open the control panel, you should see a small white container inside.
This is your drum switch grease.  

I use a small sliver of wood, about 3-4 inches long and about 1/8 inch across to dab a little of this grease on the contacts.

[head block]

Depending on what year mill you have, it is very possible that there is a light labeled "In" on the Power Feed Module that will indicate the signal coming from the potentiometer (feed rate switch).
You may want to remove the P/F belt to make this test easier but just watch the light as you have the drum switch in the forward position and while moving the potentiometer up and down. The light should track the movement of the potentiometer smoothly, if it goes out in certain spots or is irradic, replace the potentiometer. Here is a link to Wood-Mizer's troubleshooting guide that better illustates this, as well as other possiblities.

http://www.woodmizer.com/manuals/sawmill/troubleshooting/electrical/super%20power%20feed%20checks.htm

I think I found the trouble. I took the beld off the motor drive and the motor had some rough spots it felt like so I guess it may be bad bearing in the motor. My mill is a 1999.

[logwalker]

They have a used feed motor on the WM website. Look in the WM sponsor page. I saw it the other day. Joe

[Chico]

You can probably have it rebuilt at a local shop cheaper than a used one and you know what you have or if you buy another have it rebuilt for a spare jmo Replacing the bearing bushing and brushes aren't too hard if you have any mechanical apptitude which it seems you do don't be afraid to take it apart and lok at it if it's going to have fixed anyway get familar with the inner workings
Chico

[Chuck White]

I agree with Logwalker, check out the Wood-Mizer used parts!  Here's the link.  http://www.woodmizer.com/us/usedparts.aspx

The used parts aren't just "used", they're refurbished.

They're considerably cheaper than new parts.

[MartyParsons]

 





I thought this might help. Here is a Forward feed motor dissembled. There is a bushing on the brush end.
I have also included a picture of the tool needed to reassemble the motor. I removed the motor on a service in the shop and checked the brushes every thing ok at 1500 hours. We cleaned the motor and reassembled. The bearing on the front is not available through WM parts but was available through local parts store. If you decide to replace the bearing in the front you will need a press to remove and replace. Make sure you locate the bearing before removal and after replacing the new bearing. I dont think you could do a field replacement of the bearing. These motors are good and I dont see many replacements.
Hope this helps!
Marty

[Tom]

That tool sure looks better than the two thin pieces of wood I used.   I had to develop a whole new set of arms, hands and fingers.  :D :D

[Chuck White]

That tool sure looks better than the two thin pieces of wood I used.   I had to develop a whole new set of arms, hands and fingers.  :D :D

I agree Tom.  Last time I checked the brushes in my feed motor, I used 2 popsicle sticks to hold the brushes in.  But, it did work! ;D

[head block]

[img width=500 height=375]https://forestryforum.com/gallery/albums/userpics/11823/1312/LT40_Standard_Motor.jpg[/
I thought this might help. Here is a Forward feed motor dissembled. There is a bushing on the brush end.
I have also included a picture of the tool needed to reassemble the motor. I removed the motor on a service in the shop and checked the brushes every thing ok at 1500 hours. We cleaned the motor and reassembled. The bearing on the front is not available through WM parts but was available through local parts store. If you decide to replace the bearing in the front you will need a press to remove and replace. Make sure you locate the bearing before removal and after replacing the new bearing. I dont think you could do a field replacement of the bearing. These motors are good and I dont see many replacements.
Hope this helps!
Marty

Where did you get the tool,are did you make it?

[MartyParsons]

It is included with the new brush kit.

I would not recommend grease on the bushing it does not need lube. If you grease it the dust from the brush wear will stick to the grease and create abrasive and make the bushing fail.

Just to put it in prespective I have never installed a brush kit on these motors. I have sold some to owners and have checked / cleaned many during service. The brushes must wear long. What have you seen?
Marty

[beav39]

headblock i just replaced mine no more than a few weeks ago,what a difference the new motor made !just like it was when it was new     2001  woodmizer lt40 hdydrualic

[head block]

headblock i just replaced mine no more than a few weeks ago,what a difference the new motor made !just like it was when it was new     2001  woodmizer lt40 hdydrualic

did you get a new one or have yours rebuild?

[head block]

Thanks everybody for the help. I took the motor apart and replaced the bushing and everything working so far. This is a great place to learn and get help fixing your mill.Thank again.
headblock