Hard cold start

[MrDee]

My car starts harder after sitting for a few days or a week. It fires off instantly after its been started, but the longer it sits, the harder it is to start. You have to pump it 20+ times while cranking. It will finally start, then the rest of the day, fires instantly. " FB experts all claim its the gas that boils out of the carb after it sits. That's not it. After I crank the car up and it starts, I shut it off before it even warms up. I'll let it sit a few days and it's hard to start again. I changed to a new Edelbrock carb, no difference. Yes, the choke and fast idle are set perfectly. When it dies finally start, the fast idle runs the rpm at 1500 rpm. The choke warms up fast in the summer and is fully open after running for a minute. And as I said, if I start it every day, it fires up instantly. But when it sits for a few day, I crank and crank and pump and pump.

 

[dadsbee]

We've done this a hundred times here... hose loose sucking air in or fuel pump check valve letting the line bleed back to tank.

 

[sam dupont]

After setting, hold the choke plate open and pump the throttle. Is it squirting gas?

 

[dvw]

Easy enough to test. Use a squirt bottle and put some fuel into the vents. If it starts right up the bowl was empty. A auxilary electric pump will cure the empty bowls on start up.
Doug

 

[WileERobby]

When the car sits for days, do you FIRST check the carb to see if it squirts fuel when you actuate the throttle by hand ? ( Before you do anything else ? ) It's not fuel "boiling" it's the fuel EVAPORATING. You changed the carb for no reason.

 

[dadsbee]

Sitting for over 4 months ....

 

[Sam69sat]

I have that problem if my car sits too long. I chalk it up to fuel bleeding back or evaporation. Instead of burning up the starter, i fill the bowl up with one of these.

 

[Geoff 2]

Fit an elec fuel pump, such as a Carter #4594. Use as stand alone, not in conjunction with the stock pump.

 

[moparedtn]

When the car sits for days, do you FIRST check the carb to see if it squirts fuel when you actuate the throttle by hand ? ( Before you do anything else ? ) It's not fuel "boiling" it's the fuel EVAPORATING. You changed the carb for no reason.

This simple test is what convinced me of the root cause (fuel is evaporating from the carb).
Upon considerable research into it, turns out a lot depends on which of dozens of fuel compositions
available in this country your locality happens to utilize - and how much of it is corn squeezin's specifically.
It's also a theory, in this forum and elsewhere, that the Eddy carbs are more susceptible to it than the
Holleys for whatever reasons.

For further reading on this subject, I suggest you utilize this forums' SEARCH feature:

You are not alone in this - many folks experience this phenomena in otherwise mechanically sound
old cars. It is more than likely the crap fuels we're forced to use these days that's the cause of your
complaint.

 

[toolmanmike]

My car starts harder after sitting for a few days or a week. It fires off instantly after its been started, but the longer it sits, the harder it is to start. You have to pump it 20+ times while cranking. It will finally start, then the rest of the day, fires instantly. " FB experts all claim its the gas that boils out of the carb after it sits. That's not it. After I crank the car up and it starts, I shut it off before it even warms up. I'll let it sit a few days and it's hard to start again. I changed to a new Edelbrock carb, no difference. Yes, the choke and fast idle are set perfectly. When it dies finally start, the fast idle runs the rpm at 1500 rpm. The choke warms up fast in the summer and is fully open after running for a minute. And as I said, if I start it every day, it fires up instantly. But when it sits for a few day, I crank and crank and pump and pump.

Look in the fuel and carburetor threads here. There are 2 threads saved at the top of the list about this subject.

 

[68BabyBlue]

This simple test is what convinced me of the root cause (fuel is evaporating from the carb).
Upon considerable research into it, turns out a lot depends on which of dozens of fuel compositions
available in this country your locality happens to utilize - and how much of it is corn squeezin's specifically.
It's also a theory, in this forum and elsewhere, that the Eddy carbs are more susceptible to it than the
Holleys for whatever reasons.

For further reading on this subject, I suggest you utilize this forums' SEARCH feature:
View attachment 1711381
You are not alone in this - many folks experience this phenomena in otherwise mechanically sound
old cars. It is more than likely the crap fuels we're forced to use these days that's the cause of your
complaint.

Done some experimentation with my last three GTXs (all with completely stock fuel systems, Carter AVS, AFB in the Hemi). Had fuel pump issues with two, hard starting after sitting, same day, like after an all day car show. Car would start instantly after priming the carb, new fuel pumps eliminated most the same day starting issue, but ethanol free gas solved the problem completely. The Hemi ran okay on ethanol free when I drove home from Virginia, but had issues when I started running 10% ethanol. Current GTX 440 starts well under most conditions, but I've noticed fuel making a difference. Car starts like it did when new on ethanol free.

Sometimes the stations run out, and I'm stuck running 10% ethanol. If the car is running the 10%, I'd rather prime it, than put the starter through the extra cranking. Hot starts haven't been a problem, even with the ethanol, unless the car sits all day, in hot weather. This happened at Carlisle, but Bob Miller was able to make it start by manually holding the automatic choke shut while I cranked. Back in the day, he fiddled constantly with the original on Baby Blue.

Baby Blue had a Holley electric fuel pump that Bob installed in the 70s, and that car never failed to start on the first spin of the starter, under all conditions, with whatever gas I used. So, in my experience, you have a result dictated by both fuel quality, and the mechanical quirks of your particular car.

 

[toolmanmike]

Something else for you big block guys is the wear and length of the fuel pump pushrod. Just an FYI.

 

[R413]

Ethanol free makes a difference.

Otherwise open the hood, fill the float Bo wls, look over the engine and check fluids, etc. not a big deal to spend a few minutes doing this.

Along an electric pump,is not the fox for,me, more added on bullshit that's unnecessary and more possible leak points for fire in the years to come.

 

[moparedtn]

Something else for you big block guys is the wear and length of the fuel pump pushrod. Just an FYI.

More something that's indicated when fuel pressure drops, honestly. If the pump is delivering
enough fuel for all demand situations, I leave the pushrod be.
I discovered my first severely worn one when the car would literally run out of steam (gas) during
hard acceleration runs.

 

[Davefinan]

The new formulations of gas makes the most sense. When I was I kid , I drove these same cars we have for a hobby these days. I usually had two beaters so one would sit for awhile. I don’t remember ever dealing with these hard cold starts.

 

[moparedtn]

Done some experimentation with my last three GTXs (all with completely stock fuel systems, Carter AVS, AFB in the Hemi). Had fuel pump issues with two, hard starting after sitting, same day, like after an all day car show. Car would start instantly after priming the carb, new fuel pumps eliminated most the same day starting issue, but ethanol free gas solved the problem completely. The Hemi ran okay on ethanol free when I drove home from Virginia, but had issues when I started running 10% ethanol. Current GTX 440 starts well under most conditions, but I've noticed fuel making a difference. Car starts like it did when new on ethanol free.

Sometimes the stations run out, and I'm stuck running 10% ethanol. If the car is running the 10%, I'd rather prime it, than put the starter through the extra cranking. Hot starts haven't been a problem, even with the ethanol, unless the car sits all day, in hot weather. This happened at Carlisle, but Bob Miller was able to make it start by manually holding the automatic choke shut while I cranked. Back in the day, he fiddled constantly with the original on Baby Blue.

Baby Blue had a Holley electric fuel pump that Bob installed in the 70s, and that car never failed to start on the first spin of the starter, under all conditions, with whatever gas I used. So, in my experience, you have a result dictated by both fuel quality, and the mechanical quirks of your particular car.

Fred runs like dog poop on the ethanol mixed stuff, loves the straight stuff - and yes, the mixed stuff evaporates from
the carb quicker than pure gas.

 

[moparedtn]

The new formulations of gas makes the most sense. When I was I kid , I drove these same cars we have for a hobby these days. I usually had two beaters so one would sit for awhile. I don’t remember ever dealing with these hard cold starts.

Yep. Before our beloved overlords started mandating all manner of crap be added (and/or subtracted) from our gas,
this wasn't nearly as much an issue for sure.
I don't even remember vapor lock issues on my rigs way back before they started all that nonsense - although Fred
doesn't suffer from that condition to this day, no doubt in part because he never sees ethanol anything.

 

[68BabyBlue]

The new formulations of gas makes the most sense. When I was I kid , I drove these same cars we have for a hobby these days. I usually had two beaters so one would sit for awhile. I don’t remember ever dealing with these hard cold starts.

My first GTX often sat for a week or more during my early years as a truck driver, always started right up when I got back.

 

[eldubb440]

how does fuel in the bowl bleed back into the tank? it doesn't.......... it evaporates

fuel in the line? I suppose it's possible

 

[toolmanmike]

More something that's indicated when fuel pressure drops, honestly. If the pump is delivering
enough fuel for all demand situations, I leave the pushrod be.
I discovered my first severely worn one when the car would literally run out of steam (gas) during
hard acceleration runs.

Yes, a short pushrod doesn't cause fuel evaporation but you don't know what other members don't know. You know?