"I would be interested in anyone who could post something negative about this ign., as I have yet to hear of a failure"
I'm not making this reply to "dis" the Bosch ignition as I've had a '75 distributor in my '69 140 for at least 10 years with no issues. But over the course of many years of servicing Volvos I have had occassion to make repairs on this type distributor (system used in the early years of the 240 series B21) so I want to let potential users at least be aware of the possible faults. Most common would be a failure of the coil winding in the distributor due to shorts in the winding. This ususally gives plenty of warning with unexplained temporary failures--the motor stops running after being fully warmed up--then will restart after a cool-down period. Eventually the failure will become permanent with a no-start condition and requires replacement of the winding. The second fault I've found is uncommon but possible. What can happen is the tiny pin which locates and secures the reluctor can disintegrate (rust) allowing the reluctor to shift position on the distributor shaft throwing timing off. Symptoms can be hard starting, no start, severe pinging and/or backfiring. The fix is simple enough with the repositioning of the reluctor and replacing the pin. I hope this doesn't discourage anyone from using this type dist. as I found the improvement over point & condensor to be dramatic. I installed my system in the dead of winter and made no other changes at the time. My cold start-ups went from the motor cranking 4-5-6 revs before firing to an almost instant start. -- Dave
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