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Power valve motor


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watfordhorn
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Power valve motor

Fri Aug 30, 2013 10:21 am » Post: #1 » Download Post

I am just getting my 96 MC28 ready for the road, it looks to be an extremely low milleage bike, i would not be suprised if it was less then a couple of thousand km's looking at its condition and the wear on its discs.

Problem is it came with a completely non working PGM, I figured it could be just the wrong card but buying another is a bit risky but it would be nice to know its actual milleage.

Anyway....the problem..

I tried the PGM in another bike and its definately dead, no biggy as I have a spare but performing the usual checks before I run it I decided to make sure the valves were free so i didnt blow another one, guess what, they hardly moved, I disconnected the cables, and still the pulley on the motor hardly moves, so I took it off to test it by connecting it up to a battery to the bottom two terminals on the plug.....nothing, I do the same check on a spare powervalve motor and it moved fine. Problem is this is a MC21 motor and although its the same part number the wires are different colours...as its the same part number I think it should be fine as a replacement....anyone know any different?

My other thoughts are maybe this blown motor fried the PGM hence it having such a low milleage.....but what could of caused the motor to fail? The valves are all free and easy to turn by hand.
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watfordhorn
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Fri Aug 30, 2013 10:28 am » Post: #2 » Download Post

Scratch that...I thought the valves were moving fine but the top one does stick sometimes, I guess thats whats blown the motor? But the question is the same...are the motors compatible? Could a blown motor completely fry the PGM or would it of just done the powervalves circuit?

Glad I checke before melting another PGM!
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StephenRC45
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Fri Aug 30, 2013 11:27 am » Post: #3 » Download Post

There were two MC21 servo motors, both with different wiring. I managed to blow a F3 PGM up by pluging the wrong year servo in once.

So yes, it's possible the servo could kill the PGM.
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watfordhorn
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Fri Aug 30, 2013 11:31 am » Post: #4 » Download Post

Bugger, i would of thought that same part number should be same form/fit/function, oh well. I guess it could be safer to buy a new one for the right year?

Do you know if your two different ones had the same or different part numbers? The wiring is the same it's just the colours that are different.
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StephenRC45
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Fri Aug 30, 2013 11:35 am » Post: #5 » Download Post

They have the same wiring but the pin numbers of the connectors are different. Eg positive feed used to go into pin one, now goes into pin two for example.

I don't recall which was which but two wires had been swaped in the block connector.
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watfordhorn
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Fri Aug 30, 2013 12:29 pm » Post: #6 » Download Post

Sounds about right.

Blue wire goes to the same on both
White wire goes to the same on both
red/white goes to bottom left on one (MC21)and top right on the other (MC28)
red/yellow in top left MC21 and black white in bottom left of MC28

I guess I need to be looking at the wiring diagrams Sad
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watfordhorn
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Fri Aug 30, 2013 1:26 pm » Post: #7 » Download Post

Cheated......opened them up and checked where the wires go (as I cant be sure whats going on where in each PGM).

Basically they are the same inside, same components, but with the red/yellow wire in MC28 motor replaced with red/white in MC21, and red white in 28 replaced with black white in 21

Although I think I got confused with the colours positions earlier, anyway, the long shot is I am happy now to fit it as is....but I am not repsonsible for anyone else swapping motors between bikes Wink
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