Help Misfire

Neilr

Neilr

Member
Hi I have a terrible misfire now. I had fitted accuspark electronic ignition kit. It ran well to start with. The timing seems all over the place. It seems to be running rich. I have changed plugs and have spark at all cylinders checked with spark testers. Any one have any ideas.
Thanks Neil
 
Make sure your coil is a correct match for your electronic dizzy. But possibly your best bet would be to take it to a good rolling road tuner who can test everything and set it up correctly. Probably cost you around £150 but may save you a lot of time and money in the long run.
 
Its the same whether on points or electronic. I think my next move is compression test and then remove rocker covers. Perhaps it could be a lifter or valve issue. As it was running fine and started to misfire for no apparent reason. I don't believe it to be fuel related as I have not touched that side. Carb pistons are free though and there is oil in them. Only thing I have noticed is advance is not working. Checked with vacuum gauge. I have tried to move the arm but if feels seized.
 
Try to isolate which cylinder(s) is/are misfiring and investigate there rather than randomly looking.
 
I have spark going to each cylinder checked with spark testers I only have 4 so can only do bank at a time. I have tried taking leads off one at a time but this does not seem to help as I cannot detect any difference. This is why I am looking towards valves or lifter maybe even a pushrod.. What about inlet manifold gasket?
 
Neilr said:
I have tried taking leads off one at a time but this does not seem to help as I cannot detect any difference.
Click to expand...

Maybe every single one of the leads you pulled off isn't doing anything then.....

Just because you have a spark that doesn't indicate that that particular cylinder is working, or if the spark that you see is occurring at the right time. If you've checked the plugs and they're all black then it's running rich, so set your timing and then set the carbs. You could clean the plugs again and while they're out do a compression check to see what you've got. Inlet manifold leaks will make it run weak, not rich. Vaccuum advance is only an economy device, and centrifugal advance if seized will give a loss of performance, but will affect all cylinders equally.
 
Thanks is there an easy way to set the carbs. I don't have a airflow meter or colortune (yet). I have set timing over and over but will check again. Oh and there does not appear to be an play in the distributor.
 
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