oops! fried my pgm :-(

[nicko]

if anyone has a pgm suitable for a mk3 (md24) available i would like to buy it.

in the meantime ... i came across this int'restin' dissection site
http://mastercircuits.blogspot.co.uk/20 ... oblem.html

[gregorious77]

just send it off to Nick the Greek

[fallenmikethebike]

^^^^+1.
Mike

[nicko]

nick reckons he doesn't fix the no spark problem

i've pinned the problem down to a duff regulator/rectifier which in turn broke the sparky side of PGM. Got a replacement Electrex reg/rec so now face the problem of where to place the larger unit.

[gregorious77]

I put mine where the horn goes then moved the horn.

[nicko]

thanks to Andrew Firman who donated an untested Mk3 PGM to the cause i now have two broken Mk3 PGMs so have been tempted into investigating if i can, with the help of a mate, mend one of 'em

The first task was to hacksaw through the plastic case, separating the connector from the case too.

The circuit board is submerged in a rubbery potting compound. Experimenting with a mini temperature controlled hot air blower (designed for soldering/unsoldering surface mount electronic components) i found that 270C at 75% airflow resulted in the rubbery stuff becoming crumbly. Using the photos at
http://mastercircuits.blogspot.co.uk/20 ... oblem.html
as a map i have started excavating the circuit board.

[fallenmikethebike]

Well done, if you have a sufficiently inquisitiveness nature to carry through with the repair, the broken component will be pennies to repair.
Mike

[nicko]

my solution for where to mount me electrex reg/rec was inside the airbox (think i read about it on here somewhere...)
welded washers onto 6mm stud & bonded them to airbox cover. its yet to be tried in action, quite a fiddle to get cover back on airbox but the reg/rec will have fresh air @ won't get clogged up

i haven't made a hole for the wires to exit yet