CB750C Cylinder 1&4 not firing.

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Zoocrewsgarage

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I have swapped out the coils. I can fire both coils when hooked up to 2&3.
I can swap both spark ignitors TI . I have one, extra they all work on 2&3 cylinder side.
I can only fire the 2&3 cylinder from the pulsar.
Is there any other test i can do to rule out or confirm the 1&4 pickup is bad.
The only replacement is used parts?
Any help would be appreciated.
 
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SenseAmidMadness

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That sounds pretty definitive to me that it's an issue with the 1&4 timing pickup, but that doesn't rule out a wiring issue between that pickup and the spark units. I would check wiring continuity in a few places with a multimeter to make sure there's not, say, a cooked wire in the timing plate's pigtail.
 
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tszym

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Zoocrewsgarage said:
I have swapped out the coils. I can fire both coils when hooked up to 2&3.
I can swap both spark ignitors TI . I have one, extra they all work on 2&3 cylinder side.
I can only fire the 2&3 cylinder from the pulsar.
Is there any other test i can do to rule out or confirm the 1&4 pickup is bad.
The only replacement is used parts?
Any help would be appreciated.
Click to expand...
Did you resolve? What fixed it?
 
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tszym

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Zoocrewsgarage said:
Pulse generator under left side cover. There are no new ones available. Have to source a used one. About $120-160. I checked everything switched coils and TI modules.
Click to expand...
OK, Thanks Zoocrew. I replaced it, (assuming pulse generator = the OKI MPS-200) not my problem. Swapped and replaced.
Or perhaps you are referring to engine left side cover where the cdi 'pickups' are....
I apologize for possible nomenclature differences. I find different folks describe components by different names.
My actual problem is no, or too weak spark on 2-3. Found another post that seems to match my issue..
Have not had a chance yet to test his theory, but will....
 
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Zoocrewsgarage

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tszym said:
OK, Thanks Zoocrew. I replaced it, (assuming pulse generator = the OKI MPS-200) not my problem. Swapped and replaced.
Or perhaps you are referring to engine left side cover where the cdi 'pickups' are....
I apologize for possible nomenclature differences. I find different folks describe components by different names.
My actual problem is no, or too weak spark on 2-3. Found another post that seems to match my issue..
Have not had a chance yet to test his theory, but will....
Click to expand...
It’s inside the left cover on the engine . Controls ignition spark. And advance. Mine was bad. I only had Spark on 2-3 and not 1-4. There is also specs in the service manual online .
 
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tszym

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Zoocrewsgarage said:
It’s inside the left cover on the engine . Controls ignition spark. And advance. Mine was bad. I only had Spark on 2-3 and not 1-4. There is also specs in the service manual online .
Click to expand...
Hey Zoo, thank you for clarification. And thanks for the ebay link to view. Eby has been very handy for my '82 F.
 
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