Vapor lock can happen even when it is cold

50C8DAN

On Sat. we took the '54 Hornet to a local Christmas parade we had not been to in several years.  We were in line and the line up and move, line up and move process went on for about 90 min.  I finally started shutting down the car and waiting since it was just a waste to sit and idle.  Well just as we were ready to pull on to main street, the thing we all hate happened, it wouldn't start.  Popped off the air cleaners and no fuel.  I also had not put any tools in the trunk yet!  I guy had a set of metric open end wrenches and luckily the 13mm worked well enough to get the fuel line loose.  Finally after about 20 min. it fired up, but we fell out of place and were the last ones in line, missed the judging but made the parade.  This is the first and only time a Hudson has had vapor lock on my watch!  

Jon B

Are you sure it was vapor lock, Dan?  Could it have been a temporary blockage in the fuel line, or the needle valve somehow stuck, "shut"? 

It could be any number of things besides vapor lock.  For example, in my '37 I have a phenomenon whereby the choke valve sometimes jams completely shut when I'm starting the car.  And then, absolutely nothing will get the car started.  I always blamed the problem on other things, then last year during another such episode a friend pulled the air silencer off to reveal the jammed choke.  I flipped it back open, and the car started immediately.

railknight

I recall reading from a book on vintage car ownership that driving your old vehicle in a slow moving parade is hard on its cooling system and thus you should avoid participating in such events with your car.  I always keep a jug of water in my '53 Super Wasp just in case of vapor lock.  Pouring water on the fuel pump usually does the trick other than waiting for the fuel to return back to a liquid. 

iceblade10

Yeah, I bet the engine was at max temp due to just sitting and idling for so long.  Idling in a Hudson for 90 minutes seems kind of hellish to me, honestly... LOL.  Anyway, it is my understanding that once the engine bay is hot, and you shut the engine off, the fuel in the carb bowls can boil off (amongst other things), causing the vapor lock.  This sounds exactly like what happened to you.  One way to combat this is to install an electric fuel pump.  My uncle installed one in my car, and I'm so glad he did.  I can fire the car up in seconds even if it's been sitting for months.  I can also instantly get the fuel to where it needs to be if I have vapor lock.  By virtue of this, it makes life a lot easier for your starter.

50C8DAN

Yes it was vapor lock and yes it was just like Iceblade describes.  I only idled for about 15 min at at time.  Would never let it go 90 min, although it was cool outside and I have an aux. fan.  There was zip fuel in the carbs and nothing in the upper part of the fuel line.  Like I said I just unscrewed the line and a few cranks and had plenty of fuel.  I will probably put an electric fuel pump on next spring.  

53jetman

That's why I install a Carter Rotary Vain Pump back by the fuel tank on all my Hudsons and disable the mechanical pump on the side of the engine.

50C8DAN

Jerry which model Carter did you use?

RichardD

Yes, my first & LAST EVER parade was yesterday; too hard on the cars. DON'T anyone else put a car in a parade.

53jetman

50C8Dan  -  I use the 6v Carter available at O'Reily's everywhere

cchancel

I ran a 1951 Super 6 in a Veteran's Day parade and the 262 ran beautifully! It was basically idled for 90+ minutes, stock fan, stock radiator, ran cool, and operated fine using a double-action mechanical fuel pump. On the other hand, it wore me out with the slow driving: clutch, brake, gas, clutch, brake, gas, . . . .

You might try this heat shielding on the fuel lines in the engine bay: https://www.amazon.com/gp/product/B00FS6CIA6/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

It seems to have reduced my car's propensity to vapor lock.

iceblade10

RichardD said:

Yes, my first & LAST EVER parade was yesterday; too hard on the cars. DON'T anyone else put a car in a parade.

Oh no... what happened?

iceblade10

The Jaycees have a small parade down the main street of my town every May I think.  In addition to classic cars, they also have antique tractors.  The John Deere guys, Ford guys, and Massey-Ferguson guys all run seperately - brand loyalty is strong, I guess... LOL.  Anyway, I did it one year, and it was an OK experience.  There were only maybe 15 or so cars, and I have an automatic, so it wasn't too bad.  My car tends to smoke a bit when hot, so that's kind of embarrassing, but other than that no issues.  The cars are expected to throw candy out to the kids in the crowd (who lie awaiting w/ bags), so that's kind of fun.

Uncle Josh

Smart parade organizers put the cars in front.  Smart car owners insist on it.

Per

In my 35 Hudson the gas tank is connected to the mechanical fuel pump as usual.  I put a T fitting between the mechanical fuel pump and the carburetor.  Onto this T is a flexible fuel line going behind the front seat to an electric fuel pump (from a 1980 Honda).  A small container of gas is there to supply the pump.  A 12 volt battery of the type used in a portable starting booster/tire filler powers the pump.  

When the car has been standing, I use the electric pump to fill the carburetor (the advantage mentioned by Iceblade).  This has the benefit of being able to use fresh gas to start the car.  Some years I hardly used the car, so the gas in the tank had a chance to get old.  

I haven't had a problem with vapor lock, but it is reassuring to know that if it would happen, I have the electric pump.