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TR4/4A Running Badly

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KVH

KVH

Obi Wan
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Today my 4A seemed to take forever to warm up, and then it kept wanting to drag and almost stall on take off from stop lights. It ran OK once underway, but sluggish, skipping and missing on take-off. I wish I could isolate the problem. I cleaned the float bowls and the needles fall freely. The fuel filter is new and clean. The timing is good. I'm suspicious about my Pertronix distributor, but won't stress over that right now. Do I need to get rid of my PCV valve? I have a draft tube, so it's not needed, but I wish I understood more about what's going on. Plugs are brand new. Same for the coil. Uprated Flame Thrower.
 
What are you using for plug wires? Some Pertronix units require resistor wires to be used. I found out the hard way, once I changed my solid wires to resistor wires the car ran great.
 
If it starts quickly and easy, then its not the pertronix ign. If you have ZS carbs, check the rubber diaphragms. Next look at the sparkplugs and tell us what they look like.
Marv
 
From personal experience, two things that caused poor running/missing with Pertronix: (1) Poor battery ground and/or engine ground. (2) A failing coil. Slow to warm could be your thermostat staying open.
 
If the thermostat stays open Jay's right , it will take forever to warm up in colder weather like 40 degrees F ( verified last week). Does it help when you pull the choke out a bit ? If so , drop your mixture nuts a few flats.
 
Well, I adjusted the mixture on the near carb, opening it up just three flats. Suddenly it all runs perfect. Actually, a slight sputter in 2nd gear, high RPMs. That's OK, but what's with the carb mixture? Three flats shouldn't be such a huge big deal, should it? Do I perhaps have a defective needle? It seems centered and the piston falls correctly.

Also, when I choke the car from cold it very quickly fouls the plugs. I can't figure why that's so sensitive either. And, yes, I do have resistor wires on the Pertronix Distributor.
 
That isn't a lot but all that is needed to burn efficiently with the cooler air. As the engine builds heat the air and fuel atomize better so the choke goes in but the incoming air is still cooler therefore a bit denser and requires just a bit more fuel at running speed. Enrichen the mixture at least a couple flats on each in the fall and lean the same amount in the spring and you won't be all over the place ! I had mine out the other day and yes you can overchoke them! Its as much like running a farm tractor as you 'll find - and that is the best quality about them !!!
 
Have you cleaned the needles? This new gas attacks the brass and builds up on it, which is going to change mixture.
needles should be shiney brass color, not green or black.
Marv
 
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