Getting AF Alcos running again after layoff

Hi -

Once-running "original" engines that ran no longer do - it's the reverse unit.  PLEASE DON'T WRITE IN TELLING ME TO REPLACE THE REVERSE UNITS.

There's got to be some trick to get these things cycling again, they stop working after they sit too long.  Right now they just light up

but the reverse unit doesn't kick in.  Can anyone tell me from experience what to try and in what order?  I read about fingers, etc but

don't see them or how to remove/clean them (if that's a thing).  I see the drum that's supposed to rotate, but the latch that sticks through the outside doesn't

seem to move anywhere so I won't try and force things.  Also, the "lever" at the end - that's (I think) to lock it in one direction?  

Thanks for your help -20180512_093223[1]20180512_093237[1]20180512_093254[1]20180512_093303[1]





Photos (4)
Original Post

Okay ... good info ... so the latch goes through a slot and is limited as to how far you can "swing it from side to side" - as you suggested I moved it as far as it will go to one side, now (and yes, I'm an idiot) the engine runs in one direction, at least, but won't go into neutral and do the reverse cycle, is there some adjustment so that the lever moves between - are we looking for 3 states?          both directions / neutral no direction at all / one direction operation?



It sounds like the brass pawl is not dropping without power and is stuck up. Something I learnt many years ago is that the top edge of the brass pawl will pick up dirt etc and this causes it to stick to the top of the black reverse units frame.

Just leave the locking lever in the off position which you have done and and push the brass pawl down so it drops. Then get a Q tip and clean the top of the pawl to remove the grunge, you might find it comes off a green colour. Then use the other end of the Q tip and clean the corner of the metal frame where the pawl locks into so that you remove any other bits of dirt. Do not oil anything , these reverse units do not need oil anywhere from my own experience.

I'm embarrassed - I'm 2 kinds of engineer and don't know what a pawl is - can you describe it and repeat what your saying, tailoring it not only for "dummies" but "idiots"   LOL   - seems like you've hit the nail on the head - what do you use for cleaning solution?  Is acetone a no no?  Rubbing alcohol?  ????

Thanks  so much!



Picture two shows the end of the brass pawl in the opening of the reverse unit in the top right position. It sounds like it is stuck in this position with the locking lever in the off position and power cut.

Just pushing it down with you finger will see it drop to the bottom of the opening. The bottom of the pawl will be resting on the bottom of the black frame. The top of the pawl will be exposed. I don't use anything on the Q tip to clean the top but there is no reason why you can't use rubbing alcohol, just make sure you use the other end to dry it off completely. Then do the same on the frame using picture two as reference and use another Q tip to clean the top right of the opening of the frame.

i find that this gives about 95% reliable cycling of the pawl dropping when the power is cut to it.

As it hasn't been used for a while I would also look at removing both side frame assembly's to get access to the axles and gears. Depending on when they were last lubricated I would drop some oil on the axles either side of the gear so that it goes into the chassis. It may also need the old grease removing from the gears and new grease applied. The other place it will need oiling is on the armature bearings. These are more tricky to get to when it is all assembled together. I use a modified syringe with a needles end cut off to remove the sharp bit. A small amount placed on the shaft right next to the bearing is suffice. If you don't have a syringe you can use large needle dipped in some oil and transfer it to the shaft.

I believe I can see some other problems with your reverse unit which are going to cause a failure later on.

In picture four if you look to the left of the red wires you will see a metal tab that protrudes through the brown finger board to keep it in position. It looks like someone has removed or replaced it in the past and not secured it correctly to stop it lifting which will cause the fingers to not make contact with the drum. They need to be twisted by about 20-30 degrees to lock the board in position. You also need to make sure the boards are all the way down as you twist the tabs. Be careful!!

The finger board on the end where the yellow wires go to looks like it may be lifting away from the frame already.

Here are a couple of pictures to help. The first one shows both tabs verticle and in alignment to the main frame. This is the position they need to be in to remove and replace the boards. In your case you can twist the tabs with the wires connected, you don't need to remove them. A good pair of needle pliers is all you need.


The next one below shows the twists in the tabs to lock them in position. Sometimes they may need twisting a bit more, if they do, just do it by a small amount so that there is no movement of the board.



Photos (2)

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