PW 3662 question

take it to a pro

Disconnect the piston and plunger from the sweep arm and see if the piston operates properly. You may need to disassemble the piston from the cylinder and lubricate the edge of the piston with Molykote powder and oil, according to the service literature. If the piston works this way, lubricate the mechanism with Molykote powder or powdered graphite and try again.

 

Larry

 

 

 

 

 

Thanks Larry,

 

I don't believe that the piston is the problem, when I operate the sweep arm by hand with the piston still connected, it all moves freely (including the piston) without any binding or resistance as previously mentioned.

 

There are countless 3662 junkers out there. I would find one and if the mechanism works just replace the entire assembly.

 

Richard

Try the suggestion and confirm that the coil is good and works properly. This is the first step in identifying and repairing the problem.

 

Larry

It sounds as if the piston is stuck. Service it as train Larry suggested. The seal on the piston may be shot. It needs combo lubrication around the seal inside of the cylinder. Read and check it out here. 3662 Milk car

I guess that I would take the coil/dashpot assembly apart, and apply power to check whether the coil generates enough magnetic pull. I would see how strongly it attracted a screwdriver. (as Larry suggests)

As far as the dashpot goes: it is possible to put too much around the seal. When there is too much material, the dashpot offers too much resistance, and the mechanism will not work.

At what voltage are you operating?  First try to increase voltage.  You might also lubricate the mecanism at thee pivot points and where the two plates slide on each other.  Also check and make sure one of the plates are not bent slightly. m If one is bent the mechenism will still operate by hand.

Thanks for the feedback guys.

 

As stated in the original post, the piston moves freely and smoothly, along with the sweeper arms.  There's no jamming or binding anywhere in the mechanical linkages.  Same with the can sweep arm.  Tried varying the voltage anywhere between 10 up to 18 volts.  I can hear the coil humming but that's all I get out of it.  Wiring from the slider shoes to the coils is solid and good.

 

I will disconnect the leads to the coil and power the coil by itself and check the magnetism of it.  As I've alluded to earlier, it initially seems to me that the coil is the culprit, but wanted to pick other's brains in case I missed anything else beyond what I've already observed/checked.

 

I'll try working on it this weekend and see what happens.

 

Thanks again guys.

Just to give an update, I was able to verify that the coil was the culprit, I happened to chance upon an underframe with the complete coil & mechanism assembly for the same car in excellent condition and swapped them out and it's running like a champ again.

I wanted to express my thanks again to everyone for their suggestions & contributions.

Thank God for us TCA Members, eh John?