Car has a hard time starting after it's been running

[sk1nw4lk3r]

Ok, not in my Bronco, but you guys are more knowledgeable and friendly than the Mustang crowd, so here goes

We have a 66 Mustang convertible with an old, tired 302 in it, but she runs pretty strong.

Will fire up cold no problem. Couple pumps of the gas peddle, and shes ready to rock.

But after a couple miles, literally even 3 or 4 miles to the gas station to stop for drinks or anything, it doesn't want to start. I have to give it a lot of gas to get it to fire, so I definitely think it's fuel related.

Took the air cleaner off, and it will definitely jet gas into the carb just fine.

Doesn't seem to matter if it's a hot day, and it certainly doesn't matter if the car ran for a long or short time prior to shutting it off, so I don't think it's vapor lock.

Any ideas?

 

[Millercorey]

Not the expert here on the specifics, but I’ve had warm start concerns before and there’s a lot of threads that talk about this being a very common Ford-specific issue. So much so that I want to say the owners manuals even touch on it, and apparently the warm start procedure is something along the lines of depressing the gas pedal 1/4 of the way in before turning and releasing when it starts to fire. Might be all your experiencing or it could be a larger issue.

 

[svastano]

Did you check the timing?

 

[Apogee]

So a 302 was not stock in '66 IIRC, should be a 289, so we can't really assume "stock", which leads me to ask what exactly are you running for a fuel system (pump, carb, etc) and ignition (points, electronic, etc). Odds are you have some combinations there that's making your warm starts less than easy.

When my EB had similar issues, I chased my tail for a while, but adding a phenolic spacer between the carb and intake seemed to make the most difference (boiling the fuel out of the float bowls when I'd stop). Mine however is a '77 and has a 351W with a Duraspark and aftermarket Holley Avenger carb.

 

[DirtDonk]

And define "hard to start" too. Does it:

1. Crank and crank normally, but won't fire?
2. Does it crank slowly, almost like the battery is weak?
3. Does it at least try to fire at all during this time, or is it just dead until it finally fires up?
4. When it does this, where is the choke plate? If it's closing too soon it can cause an over-rich condition that makes starting harder.

Probably other things too, but fill in the details there and let's see what pops up.

Beautiful car too!

Paul

 

[blubuckaroo]

Here's the section from my '77 owners manual that gives both hot and cold starting instructions.
However,
What happens is the engine heat will transfer up into the carb, after shut down, when there's no air or fuel to cool it. The fuel will boil and spill over, into the intake manifold, flooding the engine.
Even worse than the "slow start" is the fact that now you've washed the oil from the cylinder walls and contaminated the motor oil. It's really bad for your motor.
I don't remember hot starts ever being a problem with the factory Motorcraft 2150 carb, but I have had hot start issues with my Edelbrock. I ended up blocking the exhaust heat riser in the intake manifold and installed a 1/2" wood spacer. I'm happy to say, that problem is finally licked!

 

[Pa PITT]

...Wow those guys answered Question from the Heart.. Yes this Bronco sight doesn't Badger you because you don't know .. Welcome to our world .. & Welcome to the world of owning a Sweet Classic.
....... & That's not a problem just to the FORDS.
i USED TO HAVE A PARTS STORE from 1967 until 1995... While all these Lovely ride were the CAT'S MEOW...
... bUT I sold a fix for the Chevelle also. I sold a stainless gasket sheet .. shinny on one side & dull on the other side.. I don't remember which side was placed against the carb . But one side reflected the heat back into the block & didn't let it transfer into the carb to BOIL THE FUEL.
. Some times it took a regular gasket & a stainless gasket & a gasket & another stainless & another gasket ...Some times about a 1/4 of gasket sandwich ..
But at some point we got it stopped..
.....................
.... ANOTHER TRICK We used was ... Pull you breather off & Go driver you car until you had it up to temps. Then Drive it another 15 minutes .. You just making sure it hot. Then kill it in a place where there is no extra wind.. Jump out & pop your hood . Fetch a Beer & stand there & talk a bit. Keep an EYE on your carb. May need a 2nd beer . But if you see a slight trail of smoke rising from your carb .. Then you have this issue. When you can't see any more smoke trails You've got it fixed ..
As it boils the fuel it''ll give you a little trail of smoke .. That when the rest of the fuel in dripping into your engine & washing your cylinders or flooding your motor making it hard to start.
.... How's that for the old mans memory.

 

[moses_m]

So a 302 was not stock in '66 IIRC, should be a 289, so we can't really assume "stock", which leads me to ask what exactly are you running for a fuel system (pump, carb, etc) and ignition (points, electronic, etc). Odds are you have some combinations there that's making your warm starts less than easy.

When my EB had similar issues, I chased my tail for a while, but adding a phenolic spacer between the carb and intake seemed to make the most difference (boiling the fuel out of the float bowls when I'd stop). Mine however is a '77 and has a 351W with a Duraspark and aftermarket Holley Avenger carb.

Searched this post.

Which spacer did u use? Do u remember? Running a truck avenger carb.

 

[73azbronco]

shiney side down to reflect heat back. Then I use a 1/8 phenolic spacer, even less heat transfer.

Also, a leaking carb causing vapor lock is most likely leaking float valve.