Hello K-folks,
An interesting story and unexpected solution to a rough running HiPo, that may help in future diagnostic issues.
History:
Orig. '66 K-engine that I rebuilt myself with around 2k miles. I rebuilt the Orig. Carb . Used my Spare '65 HiPo fuel pump that was used but worked fine. Orig. dist. worked fine so no updates required. Installed all new wiring, etc.
Problem:
Engine started running rough at idle and normal highway cruising, like a miss from a vacuum leak or bad gas. If I Stepped on the gas the problem would go away. I put in a fresh tank of HiTest. Problem started to progressively get worse. The last time I drove it I couldn't go over 30mph........
Easy Repair attempts:
1. Pulled all spark plugs - no issues, nice and clean.
2. Checked timing - right on.
3. Adjusted carb jets - okay.
4. Checked points -fine. Still filed and re-gapped.
5. Cleaned the condenser contacts assuming it was still good.
6. Removed fuel bowl and filter was spotless.(ordered an NOS in case)
7. @&*(%$#$%&%$$#^% getting frustrated.....
More involved repair attempts:
The next steps were to replace the fuel pump with a known functioning pump (prior to mortgaging my house to find a correct '66 unit) and then send my coveted original C6ZF-C off to get it professionally rebuilt/restored. Next would be to adjust the lifters and do a compression check. But, first things first.......
Solution:
Before removing my fuel pump, I decided to make one last call to an old racer friend, Nick Dotson, who actually purchased an early '65 hi-po coupe new from Young Ford in Charlotte, NC.
I described the symptoms and began to tell him what I'd done to date to resolve them and he interrupted me with "It's your Coil...". I hesitated and said it was new when I rebuilt the motor and continued to go over my diagnosis trials. He interrupted again and said again "It's your Coil..." only more emphatically. I said again, I replaced it with one of the high $$$ repro Yellow Tops - it can't be bad. He proceded to tell me an engine story that after several carb rebuilds, (2) fuel pumps, (3) sets of plugs & wires, timing chain, cam and lifters, and an eventual engine swap, it was the coil all along. There was no arguing after that.
Fortunately I saved all my original parts and in the box was my original Yellow Top dated B6 (Feb. 1966). I wiped off the grunge, and proceeded to swap out the nice new $$$ replacement.
Many kudos to Nick Dotson as he was absolutely right!! My Kar fired right up and the harmonious sounds of 16 solid lifters in unison never sounded better.
I pulled the old coil back out and gave it a good cleaning and a fresh coat of Krylon Semi-Flat. While it was drying, I gave Nick a call back, praised him and then thanked him for the invaluable advice.
If this experience helps even one K-member in the future, then it was well worth burning a lunch hour writing this post.
Never overlook the simple things and don't be afraid to ask your friends for a second look or a bit of friendly technical advice.
Thanks for your time......
Mark