8BA, dual 97s, old mallory with pertronix, never lets me down, always runs great, until two weeks ago Ran great on Friday at the HRR, rained like hell Saturday morning, no hood, started it, ran like shit. This usually means I gotta pull the diz cap and blast it with WD, which I did, still runs like shit. New plugs, still runs like shit. Drove 50 miles home, no power, sounds like its only running on half the cylinders. Got home, new coil, same thing. Since it happened after the rain, I thought it was ignition related, but I pulled the air cleaners and now I'm pretty sure its fuel related. The rear 97 is delivering half the gas of the front 97. At 1500-2000 RPM nothing is showing at the venturis on the rear carb, I mean nothing. At about 3 grand, there's some gas, but it's half what the front 97 is delivering. It's both barrels, so I doubt is would be a clogged jet. Before I pull the carb, is there something simple to check, float maybe? Where would you guys look first? Thanks, Rich
Test the float by submerging it in warm water and look for bubbles. Also,for what it's worth,I have had some experience with the Pertronix stuff and am not really a fan.If you have another distributor try it.
The linkage between the carbs was loose. I adjusted the linkage and now have the same amount of fuel delivery from both carbs.... but.... It still has a horrible miss, stumble. Guess I need to check spark at each hole. Rich
No spark at number 3. New plug wire, still no spark. The old mallory uses a two piece cap, and visually everything looks OK, but I just can't get spark at that post. Time for a new cap? Rich
If you have a spare plug lying around, plug it into the end of the wire and check it again. As I am the master of finding the weirdest failures possible, this past spring, I found a spark plug that had failed internally, or was somehow made wrong. It looked brand new, but just would not spark. I swapped it wit another just like it, and off it went. Otherwise, probably the cap.
I've swapped wires three times, I can't get it to fire on that post. Swapping the cap aint gunna be easy, Mallory quit making them years ago. Why won't that post fire? Carbon trail? Crack? I don't have a clue. Rich
My guess you need a new cap. After the rain I think you got moisture in the cap and when you fired the motor you carbon tracked the cap. I have had it happen to me. Put a new cap on it and probably new wires just to be sure.
Just went thru this with a buddy's 428 cobra jet in a 57 ford retractable. We tried everything. It was a new distributor with his old petronix from the former distributor installed. Ran fine, then started to miss like yours. Finallly I said, the only thing we haven't changed is the petronix. Pulled it out, put in the points and condensor and it ran fine. Guess the petronix just died on one plug. Don't know, but it runs fine now. No miss. Pat.
Just for shits and giggles spray the inside of the cap with hair spray, scrape it off of the terminals and try it. Jimb
Is it the one that you slide the wires into the Top and then screw it down? (like the one on the right)
check the fuel pump, the alcohol in todays gas can run a pump very fast, had a older piece of construction equip the gasket on the new fuel pump swelled and leaked in 3 hours. have a buddy who carries a few sets of gaskets for his flathead as his pump will go bad often, just my fyi
I'm very familiar with the dreaded 2 piece cap. Don't ask how many times I had to climb under the Hood of my Dad's Ramcharger 4x4 when I was younger...and it had a Hood!! When it rained hard enough,the water would actually run down between the wires and the cap.(Dist was right under the gap between the Cowl and the Hood) Easy to tell,the "Slamcharger" ran like crap when it rained. I'd take the cap off and sure enough,there was water in it... If you are really set on keeping that Cap,take it apart,clean the "spikes" inside the bottom half and re-cut the ends of your wires and put it back together. Usually that will "fix" the problem. If not,replace the cap with one that's more "water friendly". http://www.jalopyjournal.com/forum/showthread.php?t=421493
Well, the hairspray didn't work But, I did fix it. I lightly sandblasted the bottom of the cap, cleaning the terminals, and removing any carbon tracks that may have been there. Now I'm shooting a nice clean spark to all eight cylinders, and have a smooth running flatty. Thanks for all of the advice. Rich
The hair spray worked for a guy at the James dean Run about 10 years ago in his 54 Chevy. Got him back to Iowa (400 miles) after the show. Jim PS I wasn't kidding but sorry it didn't work for you.
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