Dry Carb after sitting for a week.

Loadrunner

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Hot start issues, unless plagued with the early electronic pickup coil issues or imilar woes related to heat affected electronic ignition components, are fuel, from fuel vaporizing, basically flooded and the only thing that starts a flooded engine is a foot to the floor, or near it. Give it some air, try not to blow it up when it starts.

Some people are better at this than others.


You can probably crank a Mopar starter for 2 minutes without hurting anything, ""throwing solder" from a hot armature.

Chrysler electrics were the best, as with the everyday repairs, like my boss first job out of school told me "I know you like working on Mopars but Chevys and Fords are our bread and butter".

The Chrysler gear reduction starter, maligned by every Chevy freak/Mopar hater out there [the 99%], went on to be copied by Nippondenso, Hitachi, others.

My voodoo procedure for starting old Mopar, with automatic choke.

1st, prime the carb, unless you do want to crank some oil up into the motor.

Like any first aid, open airway, let the gas down the manifold.

Crank engine. Always crank engine with your foot away from the gas pedal, because the choke is set and needs to stay in place for a minute before kicking down.

If it starts, keep it running.

If it starts and dies, shut key off.

Repeat priming procedure.

This time, a pump or two in case gas came up to the carb.

Crank, start.

I always shut the key off between attempts.

Never leave a key on/engine off, unless troubleshooting.
 
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75LandYacht

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My 77 NYB does it too. Stock intake, Edelbrock 1406, mechanical pump. Sits for few days and takes a Bit to get started. I look at the fuel filter (clear) and it’s bone dry. So I assume the fuel is draining back to to tank. My driveway has an incline So I would park with the tank higher than the carb thinking gravity would be my friend… Nope! Same issue, so reading about an electric booster sounds like the fix…

So! If I do this, the Mech pump should be installed where on my 77???

Tank to pump? Or pump to carb?
 

CBODY67

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Seasonal blends have been around since at least the earlier 1960s. Texaco used to advertise that their fuel was blended for "your area", back in 1963. Winter blends were usually a bit more volatile than the summer blends, for easier cold weather starting. Not sure what that has evolved into with ethanol and EFI, though.

CBODY67
 

Loadrunner

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I mount a flow thru electric fuel pump under the rig back by the tank, plumbed to the mechanical pump, operated from a toggle switch, although factory application in the Ford pumper gives you momentary action only "Hold for 20 seconds" the legend says.
 

Big_John

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Seasonal blends have been around since at least the earlier 1960s. Texaco used to advertise that their fuel was blended for "your area", back in 1963. Winter blends were usually a bit more volatile than the summer blends, for easier cold weather starting. Not sure what that has evolved into with ethanol and EFI, though.

CBODY67
I don't have a great comprehension of the chemistry involved here, so it's all my understanding and shouldn't be taken as gospel.

The winter blends have a higher Reid Vapor Pressure of 9.0PSI and the summer blends are often 7.8PSI. The higher pressure has more volatility than the lower. The summer (7.8) blend doesn't evaporate as fast as the winter blend... Some states regulate what RVP for summer gas though... New York State allows 9.0PSI year round, so that would seem like the gas doesn't change much.

Here's what the EPA has done, reducing RVP from 10.5PSI to 9PSI. It also gives state by state requirements. Gasoline Reid Vapor Pressure | Gasoline Standards | US EPA

Somehow, this doesn't make a lot of sense to me... The RVP is lower, yet we seem to be having more issues with evaporation.

Some basic explanation. Seasonal Fuel Blends Explained: Summer and Winter

I haven't found what the RVP would have been in the 70's.
 

Toolmanmike

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My 77 NYB does it too. Stock intake, Edelbrock 1406, mechanical pump. Sits for few days and takes a Bit to get started. I look at the fuel filter (clear) and it’s bone dry. So I assume the fuel is draining back to to tank. My driveway has an incline So I would park with the tank higher than the carb thinking gravity would be my friend… Nope! Same issue, so reading about an electric booster sounds like the fix…

So! If I do this, the Mech pump should be installed where on my 77???

Tank to pump? Or pump to carb?
Pumps are designed to push. The pump goes back by the tank.
 

1970FuryConv

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I have the same problem with my '66 Imp. Did a new mech.fuel pump and pushrod and it made no difference.I use 93 ,Non Ethanol gas. I had a thought that the Oil Cos. do a "Summer Blend" and a "Winter blend".I am not sure if that pertains to No Eth.gas.
I have an Edelbrock AVS 2 on my 440 1970 Fury. For whatever reason, fuel takes much longer to evaporate from that carburetor. I suppose it depends on the carburetor, but I don't have an answer as to what makes one carburetor more prone to evaporation than another.
 

i_taz

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Same problem here even though fuel still squirts no matter how long it sit's. I'm about to try a fuel check valve. They recommend putting it as close to the tank as possible....

Jack
 

marty koirtyohann

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69 Chrysler 300, 505ci, 4640S. Everything is new or recently overhauled, new fuel tank, fuel lines, fuel pump, 4640s overhauled by Woodruff, newly overhauled engine, distributor, coil, etc.. The choke is not hooked up and is open all of the time. It's Texas, it's hot, it's not the issue.

When you drive the car daily or every couple of days it starts right up. Two pumps of gas, crack the throttle blade, crank it and it fires right up, idles and drives as it should.

If the car sits a week or two, it would need to be cranked for 15-20 seconds before starting. I had spark, but no gas.
Went out today after sitting 10 days, two pumps of gas as I looked down the carb, no gas spray from accelerator pump. Pulled fuel line from carb, cranked the starter, took about 8-10 seconds before I got fuel to pump out of the line.

It appears that the fuel is draining down back thru the fuel line and leveling with the fuel tank. I wouldn't think it could siphon fuel out of the carb though. There is never a fuel smell in the garage.

Once fuel gets pumped back up to the carb, car runs and starts as it should until it sits for a week or so.

What gives?

Thx

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u have fuel leak somewhere may be a crack in the fuel bowl? if it was a q jet i woukd say it hasa bad plug in the bowl
 

marty koirtyohann

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I have the same problem with my '66 Imp. Did a new mech.fuel pump and pushrod and it made no difference.I use 93 ,Non Ethanol gas. I had a thought that the Oil Cos. do a "Summer Blend" and a "Winter blend".I am not sure if that pertains to No Eth.gas.
buy ethanol free gas if u can it will stop a lot of the fuel issues i can buy it jus 15 miles from me
its pure 91 octane gas
 

75LandYacht

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Same problem here even though fuel still squirts no matter how long it sit's. I'm about to try a fuel check valve. They recommend putting it as close to the tank as possible....

Jack
I tried a check valve as well, got it from Jegs. I’m sure you can find them elsewhere, but it didn’t change a thing, after my NYB would sit for any more than a day or so, fuel still drained back to the tank, but don’t let me discouraged, give it a shot. You may have better luck.
 

Loadrunner

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In the old days, some guys plumbed in an electric at the back just in case of a mechanical failure on trips, which has happened several times that I know of. '65 Chevy panel w/ 283 lost fuel pump on the way to Las Cruces NM, back in the 70's. Heard plenty of cussing, and lucky to have tools enough to change it on the side of the road like that.

I actually changed a fuel pump for an older gal/friend in a Chevy conversion van in a NAPA parking lot once.

Replaced many a dead in tank fuel pump in Subarus - in situ every time, typically in a parking lot - which will give you some warnings, like refusing to start correctly for a while before sudden death. This electric fuel pump death is I suspect highly related to never changing the fuel filter, which strains the pump. Change that fuel filter on schedule, and at tune up time. If you feel the car isn't pulling like it used to, plug, air filter, fuel filter, and you're good to go.

So it's only a matter a time before fuel pump dies, not a bad idea to have a backup plumbed in, which also serves as primer device.

May of these cheaper - China - pumps are too noisy for constant operation, as you can hear it buzzing quite loudly while getting fuel up to the carb, the noise subsiding as the carb fills to just a few slow pulses, a comforting sound.

Oddly enough, I'd put a brand new fuel pump on my '70 W300 sno plow, along with timing chain set, front seal - which was failing - new water pump, and during that plowing season the engine started making a knocking sound.

I diagnosed it - with a mechanic's stethoscope, do not be without one - to the fuel pump. The damn fuel pump - new - was knocking.

Got my parts guy to warranty it and replaced it, noise gone.

Very strange.

Sounded like a rod knock, not what you want to hear coming from the bottom end.
 
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Loadrunner

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It's the only gas I will use in small equipment, splitter, saws, mowers, etc, it's the only gas I will put in a can.
 

WSP

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If I'm going to prime the carb by pouring some gas in, I like to add a little oil to that gas, just to help lubricate things until the oil pressure picks up. Don't know how much it helps, but it works for 2 stroke engines.
 
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