Unregistered users may browse the website, but in order to participate in the forums and view select pages (such as "Club Contacts" and "Classified Ads") a user account is required. Click HERE to email the webmaster and request a free account. The National DeSoto Club uses real names rather than pseudonyms. Notify the webmaster of your user name preference (Johnathon Doe vs. John Doe, etc.), preferred email address, and password request.
Heat soak issue
So I have a 55 291 Firedome with a carter two barrel carburetor and the car runs perfectly fine and normal, however, once the temperature outside gets even a little warm I start to have issues but only on startup after driving for a while then shutting her down for a little bit like maybe a half hour or so. What I believe is happening is that the carb is heat soaking and basically vaporizing the gas in the carburetor. I don't think I have vapor lock in the lines because it's rubber lines from the hard line down by the frame rail to the pump and then rubber from the pump to the carb. So my question is, has anyone tried using phenolic or plastic spacers? I can't seem to find a spacer specifically made for the Carter two-barrel b&b. I'm also thinking about having a friend 3D print one but we are currently checking the specifications of the material that he uses to make sure that it can hold up to the temperatures in the engine bay. Any input is greatly appreciated, have a delightful DeSoto day!
My '59 383 2 barrel has the phenolic spacer but it really isn't the answer. I does not prevent the carb from vaporizing the gas. My solution was to add an auxiliary electric fuel pump externally near the gas tank and put a switch on the dash to control it. That way you don't have to have it running all the time but it will fill the carb with gas when you turn it on.
A lot of the problem stems from the poor gas we are getting these days in comparison to the good old leaded gas we used to get when these cars were new. Hope this helps.
"It's delightful, it's delovely, it's DeSoto"
Our March-April issue of DeSoto Adventures (to receive this magazine, join the club at www.desoto.org/membership) went into vapor lock into detail with a number of possible solutions. If you're able to get non-ethanol gas by you, that will help as it has a higher volatility point/temperature than ethanol gas.
Another possible solution is to replace your valley cover with a "high performance" version that blocks off the exhaust heat crossover if it's designed anything like my '59 383. Another club member had the hard starting issue like you with their '58 DeSoto Firesweep and after swapping the valley cover, that problem has gone away. By blocking off the heat crossover, it keeps heat out of the intake and, therefore, the base of the carb.
On a separate note, if your fuel line is rubber all the way from the pump to the carb, you should consider changing that to a metal hard line. It's generally recommended not to have a rubber line up on top of the motor where it could leak/burst and spray fuel onto a hot engine - a metal line won't do that once installed properly. I know that the 4 bbl in 1956 was a hard line all the way from the fuel pump to the filter bowl on the front of the carb.