Just before we headed for Florida, I had replaced the plug wires and distributor cap on the DeSoto 276 in the roadster, and adjusted the choke. It ran great, as it always had, until the plug wires gave up the ghost. Replacing them made it run great again, as it always had. When we picked it up the other day after having it transported down, it ran TERRIBLE again. Popping and snorting, huge flat spot and stumble accelerating, it seemed like it was running very lean. This morning I discovered the little screws on the choke body (original carb with automatic choke) weren't tight (I probable didn't tighten them after fussing with it before we left) and it was fully against the "Lean" stop. I pulled it back to where I'd had it set before, it seems to run fine again now. I've got a new 500 CFM E-carb in a box on the shelf, I've thought ever since building the car that I should get a 4 barrel intake from Hot Heads and use it. Now that it's given me a little trouble, of course the carb isn't here. I had thought it wouldn't make enough difference in the performance to warrant the expense of the intake, and it'd put the carb up into the hood top.
Reminds me of my brother in-laws promise to only drink on days that start with the letter T. I thought he meant Tuesday and Thursday ... turned out he meant Today and Tomorrow
This is purely the dance we go through with great old hot rods. Is it frustrating, yes. Is it worth it? Absolutely.
They are horrible looking, aren't they? And pricey. A cast iron low deck original is what I should look for. Or just drive it...
If a little is good, too much must be just right, correct? Not exactly so. I drove the car on a couple of errands this morning, after it warmed up a bit it was obviously running WAY too rich. I made my first stop, when I left it flooded immediately and wouldn't restart. Happily I was a mile from home, so I called my wife who came and rescued me with our daily. We went on to O'Rielley's, my second planned stop, to return a starter for her car that turned out I didn't need, where I returned it and bought some jumper cables. We drove back to the car, which of course fired right up after setting for half an hour. Then on to the gas station, my third stop, with her following just in case... It started after filling up, but obviously running really fat. When we got home I dialed the automatic choke body back a bit, I THINK I found the sweet spot, it doesn't load up, doesn't hack and cough (which is what started this whole fiasco), and doesn't instantly flood on starting because the choke closes when it's warm. I'm sure she'll be uncomfortable going anywhere in it until I've been out and about and not have to be rescued again, but it should be fine now. Tomorrow is my 70th birthday, we'll go to the beach!
If you suspect it's the choke, wire it open and run without it. I can't see you needing a choke in Florida. I ran a 258 AMC all year here in Ontario Canada. When you get a chance, convert to a cable operated manual choke.
That was the problem, it was open all the time. Evidently this little engine wants just the right amount of choke, it wouldn't run with it open all the time which is what it was doing when I picked the car up. The choke on this thing opens itself as the rpms increase. Whether that's the way it's SUPPOSED to be, I don't know, but it seems to be happy where I have it set now.
That manifold is pretty ugly. I think it was designed with a different crowd in mind and not us. If you used it on a car with a closed engine compartment it wouldn't be too bad. On an old hot rod with the engine exposed I wouldn't be too happy
In my experience if an engine is overly sensitive to choke settings it's either out of time, the coil is weak, or wrong plugs.
In fact the one engine I've ever had that wouldn't start unless choke was just so hard a completely worn timing chain. As in I removed the chain without removing cam gear lol
transported? I have had cars run bad after transporting. I guess a non running carb being transported sloshes around and picks up "stuff"? or maybe an empty carb, and the weight of the floats bouncing knocks them out of adjustment? I bet a simple rebuild will solve the issue.
People are sure spoiled by the modern electronically controlled cars that "self adjust" to the current driving conditions. Old motors always had to be manually adjusted for the climate in which they were used, some motors (not necessarily a car brand) were worse then others. Up here in the NW corner of IL, the chokes on several cars needed to be adjusted for the difference between summer and winter driving. They needed a "summer tune" and a "winter tune."
I could change plugs and see if that makes a difference. I'm kinda embarr***ed to admit it's got the same plugs that were in it when I got the motor (in our '52 DeSoto wagon) that were probably 20 years old at that time. It's a Pertronix coil, new wires, same old plugs.
Is there possibly a choke vacuum break or choke pull-off adjustment that might have been overlooked? Is it an integral or divorced choke thermostat? Where is the choke coil pulling its heat from?
Well, HAPPY BIRTHDAY anyway!! That stuff can be aggravating at best. You’ll figure it out. My 40 is kicking my ****.
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