The Craftmans Shop > New from Old

JCB 803 Saga

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awemawson:
So now it's a case of putting it all back together and seeing what happens!

I did check leakage from the windings to the spindle. Initially it was reading 5K ohms - not too concerning for a 12 volt motor, but obviously better if the leakage wasn't there at all. I gently warmed it using the workshop hot air hand drier, and the leaking slowly came down, eventually getting to about 120k ohm.

So back together:

awemawson:
so a quick bench test - just the motor as the parking wiring / contacts is rather complicated and needs the two pole three position switch that's in the machine.

Well slightly to my surprise it works ! Both speeds work and the crank goes back and forth giving the correct motion.

Popped it back in the machine, and yes the parking function works  :ddb:

So now that I'm on a roll I re-fit the wiper blade and adjust it, BUT the motor hasn't the torque to reliably move the blade, even wetting the screen  :bang:

Either the brushes need to 'bed in', or there is a short on the armature windings, or the magnets have demagnetised. I left it running for a while to 'bed in' but things didn't improve much. I may at some time take the armature out again and do a 'growl test' on it, but meanwhie I'll keep an eye open for one on ebay at less than the staggering £180 that a new one costs  :bugeye:

tom osselton:
I'm suprised the armature cleaned up so well.

John Rudd:
I reckon its all that grease you packed into it that's causing your problem...... :lol: :lol:

awemawson:

--- Quote from: tom osselton on July 27, 2015, 12:39:22 PM ---I'm suprised the armature cleaned up so well.

--- End quote ---

So was I  :lol:

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