Vapor lock may be symptom of underhood heat issues …

Tuesday, June 15, 2021

I’m breathing a sigh of relief tonight. I finally got to the Plymouth today after having it towed home Saturday afternoon when it quit. The issue I confirmed was vapor lock; the car wouldn’t start even after sitting here at home a few hours. But this afternoon, she fired right up.

I’ve determined that a fix to the vapor lock problem is probably going to take an electric fuel pump and a return fuel line back to the tank. An electric pump with that return line can keep cooler fuel flowing through the system.

In addition to vapor lock, I’m not sure there’s not a bigger issue with the car running just too damn hot. The previous owner replaced the radiator, so apparently he was having heating issues too. From what I’ve read, if you run this engine without a thermostat, you’re asking for cooling problems. So yeah, I’m not sure if my car has a thermostat installed or not.

On the side of the road — where we had been sitting 30 minutes — the engine was hot (but not reading hot on the guage), and the metal fuel line from the fuel pump to the carb was extremely hot to the touch — the wrecker guy had gloves on and he pulled his hand off the fuel filter quickly, noting how damn hot it was.

I’m thinking it could also mean its time to flush the block. There’s just a helluva lot of heat under the hood being transfered to the fuel line. I think I need to go talk to Joe at A1A auto tomorrow and get his take. Its really unusual that the car vapor locked at road speed with a radiator full of coolant. It may still mean I need to move to an electric fuel pump — but first, what’s causing all this damn heat??

Gary, the guy who owned it for 30 years, ran the car the way it is — no electric fuel pump. Obviously, there’s something that’s changed. I think I need to talk to Joe at A1A to check it out.

Or I could do some simple checking … I could remove the thermostat housing to see if it has one … or I could remove the radiator hose and check that way. I can’t flush the engine block, but I can check for a thermostat.

Looks like I have some work to do. I’ll have to check with Joe at A1A tomorrow after rehab.

Vapor lock may be symptom of underhood heat issues …
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