397 coal loader

[catdoing]

can some one tell me how you swap the belt on 397 coal loader

thanks

[ben10ben]

It's been a little while since I've done it, but here are the basic steps as I remember them:

 

1. Squeeze in the two metal supports for the belt, and lift up. This should free the loader arm to rotate freely around the shaft. 

2. Take the motor cover off. 

3. On either end of the shaft that runs from the motor, there should be a small bearing box with two screws over top of it. Remove each of these screws. 

4. You should now be able to lift the entire pan and arm assembly up off the base of the loader. You may need to wiggle it a little bit to free it from the coupling with the motor. 

5. Now, if you look on either side of the pan, you will see a cam. Make some sort of mark on both each cam and on the shaft to let you know the orientation they're in. 

6. You can now remove the cams from the shaft. They normally just slip on, however sometimes they will get hung on the shaft. If they won't budge, try gently tapping the shaft with a hammer. Otherwise, soak overnight in penetrating oil and try again. If worse comes to worse, you may need to cut the shaft and replace it. 

7. Once the cams are off, pull the shaft out. The arm should now separate from the pan. 

8. You'll now need to go to the other end of the arm, where the clear plastic guard and chute are attached. These are held on by the same shaft on which the end roller for the belt spins, which is held in place by a C-clip. Bend the C clip out of the way, pull it off, and pull the shaft out. You can then pull the chute off the end, and remove the old belt. 

9. Once you have the old belt off, wrap the new belt around(you might want to lightly dust it in corn starch to keep things moving well). Then, put the chute back on(there are detents to hold it in place), and put the pin/shaft back through the roller. This is probably the trickiest part, and the only way to do it is by trial and error. 

After this, reassembly is pretty straightforward. Just be sure the cams go back on in the same and correct orientation. This is where a service manual, which is, in the long run, a small investment, can be very useful.

While you have things apart, I'd also suggest that you clean and lubricate the motor and gear box. 

Good luck, the 397 is a fun and reliable accesory. 

 

 

[GBThomas]

The July 1993 issue has an article by Ray Plummer on how to replace the bels.  Also how to tune up your 397.

George

[bfskinner]

ben10ben's instructions seem quite good.

Five additional suggestions:

Take care not to bend anything!

Between steps 3 and 4 add: Mark the top of the little bearing blocks (397-14) so that you can get them back exactly as they came out. They may appear to be symmetrical, but they're not.

While you have it apart, replace the rubber "cloverleaf" flexible coupling (397-29) that transmits power from the motor to the shaft.

Keep all oil, including any "skin oil" from your fingers, off the new belt.

http://pictures.olsenstoy.com/searchcd31.htm?itm=297

 

 

[catdoing]

THANKS FOR THE HELP THAT CAM IS PROVING TO BE A REAL BOOGER  CANT SEEM TO GET IT TO FREE UP

[Anonymous]

Apply some PB Blaster where the cam meets the shaft.  Be careful not to get the PB on plastic though. 

[bfskinner]

THANKS FOR THE HELP THAT CAM IS PROVING TO BE A REAL BOOGER  CANT SEEM TO GET IT TO FREE UP

The square shaft is the most critical piece not to bend. Try repeated applications of penetrating oil over several days. As Jim Trumbie advises, don't get it on the plastic. The trays have long been the most difficult part to replace. (Not sure whether this is still true.)

If that fails. try this: rig up a jig so that you can suspend the tray above a cup of ice water. Cool the shaft as best as you can, and apply a little heat to the cam. It may pop off. If the ice water doesn't do it, perhaps you can get hold of some "dry ice" or even one of those  spray cans that shoot ultra-cold vapor. (BE EXTRA CAREFUL with both of these options -- you can give yourself serious frostbite in just an instant.) Again use a combination of cold on the shaft and heat on the cam. Take great care not to melt the plastic due to excess heat, or to have it go brittle due to excess cold.

If all else fails, cut the cam(s) off with a Dremel tool, perhaps. When you buy a replacement, always buy two cams and make sure they match exactly. (The position of the square holes in the cams varies from sample to sample, so you can't be certain that a new one will match the old one on the other side of the tray; and, if it doesn't, the device will not work. )

Use a smooth-face pliers; or seriously taped-up Vise-Grips, to hold the shaft, and another pair adjusted just tight enough to slide on the shaft. and push the cam. Tap a little on the second tool to break the cam loose -- without bending the shaft. You will need a helper.

When you re-assemble, put some anti-corrosive grease on the shaft under each cam to try to prevent this rusted-shut situation from happening again.

Maybe some mechanic on the forum has a better idea. There are tools ("nut-splitters") that some mechanics use which might work on the cams. Good luck! Let us know how it goes.

[middivrail]

I replaced the belt on the one I have a few years ago. I ran into the same problem, the cams were frozen on by rust. I tried penetrating oil with no luck. I than thought that I would distort them a little by applying force with Channel Lock pliers. It broke into several pieces by flying in all directions. But I had replacement cams on hand. The metal does seem to be a little brittle, so that could be a option for you, watch your eyes. I bought my replacement cams at Olsens.

[catdoing]

Ok heres how i got that stuborn cam off. After soaking in pb blaster use pair offset needle nose or reguler pliers just under the cam so that the shaft will slid through.  Strike with small ball peen hammer.  Then i used small file to file the end back down. Work quite well.

Thanks for all the help

[bfskinner]

Ok heres how i got that stuborn cam off. After soaking in pb blaster use pair offset needle nose or reguler pliers just under the cam so that the shaft will slid through.  Strike with small ball peen hammer.  Then i used small file to file the end back down. Work quite well.

Thanks for all the help

Congratulations! Sounds like you did a good job. My suggestions about using two sets of smooth-faced pliers, and the other ideas about cutting (or even breaking) the cam off, were intended to avoid hammering on the end of the shaft itself, but if you got away with it without bending the shaft, more power to you. Most folks don't give the penetrating oil sufficient time -- days are not uncommon -- but evidently you did.

"Mushrooming" the end of the shaft a little is no real problem. As you noted, it's easily fixed with a little filing; but as I tried to stress earlier, bending the shaft, even a little, can be a real problem. I only wish someone would try the heat/cool technique and report the results.

[catdoing]

tried the heat thing and id say id did help to loosen up the cam