Hi all,

Long time no post. I hope you are all well!

The Mikuni carb had been molested over the years and the second barrel actuator stopped working. So I fitted a weber 32/36 and the thing went like a rocket! However, while tuning it a misfire developed and I am struggling to fix it.

When the misfire started I went to check the plugs/wires and cylinder #2 wire feel apart (only a few months old). With the wire off the engine ran the same. I replaced the plugs, wires, cap, rotor with no difference. I then played with the timing and replaced the fuel filter...nope. I am getting spark to all cylinders, verified with my timing light. May be I need to check cylinder compression?

Stuff I am not sure about;

1. when I tired to set the idle mixture, turning the screw counterclockwise does result in an idle drop. Turning is fully clockwise does not. I think I had it running rich because when driving with the engine hot, fuel was igniting in the carb <img src="/forums/images/graemlins/scared.gif" alt="" /> Not sure what to do there. I have not fitted a fuel pressure regulator yet (no dieseling). I do have one. May be that will help?

2. The secondary coil resistance is 10.5 kohms. That seemed low compared to the FSM, which says 14.5-19.5. However, coils at auto parts stores say 8.9kohms. What coils do folk use?

3. to set the timing correctly I have to retard the dizzy fully. That can't be right? timing chain issue?

Thanks all <img src="/forums/images/graemlins/kewl.gif" alt="" />

I had a similar issues with an the 2.6 in my '88. I tried everything. New plugs, wires, coil and timing. Adjusted the carb and it still misfired. What it turned out to be was a broken cam cap on the top of the head. It wasn't allowing the valves proper operation as it cammed over. Simple fix was to replace the cap. I lucked out that there was no real damage to the camshaft. Your problem may not be related, but it's worth a check.

Thanks! I will check that out <img src="/forums/images/graemlins/kewl.gif" alt="" />