Vapor Lock ?

ags290

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My son was driving his early 65 Mustang on Monday afternoon and it died while accelerating up a slight incline after a 4 way stop. This is the first time this has happened in 2 years of driving. He said that he had been driving around for a little over an hour. It was over 100 degrees outside at the time. He said that the car didn't over heat. There was coolant in the radiator and there were no signs of coolant leaks so I think we were good there. We pushed the car up the incline and into a parking lot. It had spark, and I could get it to try to start with carb cleaner. I was lazy and it was too hot to try to work on in the parking lot so I called a wrecker and had it towed home.

The next morning I tried to start the car without any luck and then took the fuel line loose from the rubber hose at the inlet filter to the carburetor. I then cranked the car over for about 10 seconds with fuel line feeding into a plastic soda bottle until fuel started pumping. I put everything back together and the car fired right up and has run fine ever since. Several startups and short trips. My guess is that it was vapor locked and I just didn't try to start it long enough before taking the fuel line loose? I went ahead and ordered a new fuel pump from Rockauto but have not had a chance to install it yet.

Should I go ahead and replace the pump?

Is the vapor lock theory a valid one or do I have another under lying issue?

Has anyone else experienced something like this?

The engine is a 170, carburetor is a Motorcraft service replacement (Holley 1940), Ignition is a Pertronix setup. I do still have the heater hose plumbed through the base plate spacer on the carb.

I appreciate any and all input!

Thanks,

Kevin
 
i have also had vapor lock issues with my sixes. usually however it goes away when things cool off a bit. you might have an issue with a clog on the fuel line as well.
 
2 me VL happens IN the carb & where u were operating is only distantly related.
I use that term abt when the venturi effect happens in the carb & ices up @ that spot
due to a lill H2O in the fuel.

It's distantly (litteratly) related cuz it would block the ability to get fuel THRU the carb therefore block a flow thru the area U wrked on.

When these conditions R right (humid air, bad gas, some other condition) U just stall out 4 awhile & can start again after a wait 4 da weather (or exh. manif heat) to warm the spot.. I had what I thought wuz VL and had it cont to return again & again on one trip such that it caused an hr run to take 3 hrs - but being under 21 I kept at it to get the parents car home (40 - 50 yrs ago).
 
I had a 1962 Cadillac that would act up when heat soaked but only on start up. I'm not familiar with one acting up while driving like the Mustang did. The fuel tank has been replaced along with both fuel filters, so I dont think I have a clogged line. This is a new one on me.
 
The best thing you can do is prevent heat from the exhaust headers or manifold.
An insulated shield under the intake can help to keep the heat off the intake.
Install a second gasket under the carburetor to intake to act as an insulator.
Heat soak is a big problem especially with headers.
 
VL would not be the nxt day too.
Fuel flows to the 'soda bottle' - good pump then (if it's done PAST that).

Is there a filter AFTER that? (There is one on the carb @ the fuleline entry on many of these -
a brass looking cylinder w/ 1 end composed of a hex nut). Change that, and any others
between there and the float in the carb.

If still having probs the carb would B nxt.

OR

if intermittent it could B the pump. 2 yrs. seems like ur not pullin up s4!t from the bottom of the tank (cloggin up the carb) but if it's the 1st time its run low & headin up the hill could shoot stuff up the line…?
 
He has driven the car since Tuesday with no reoccurrence. About 50 miles. I am going to replace the fuel pump and add a second gasket between the carb base plate and the adapter plate tomorrow morning before it gets too hot. Thanks for the advice and input!

Kevin
 
keep us informed.
I'd like to hear back even if fixed.
Hope that duz it!
 
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