85 mustang,a lot of pumping of pedal to start.

[mustangnut]

Have to pump alot to get started, but after it's running then to start you just need to touch key it's running. Must be something for a simple fix to do. choke or fuel ? LMK Thanks! Fran

[mudgepondexpress]

Good chance the choke isn't setting, dying choke thermostat or very sticky linkage.

I am guessing this is 4V 5.0?

Kenny

[gr79]

Had same problems with 2.3 engine Holley 5200 model carbs.
Not giving right amount of fuel to start.
Figure it's carb bowl was empty before startup.
Extra cranking fills bowl back up. Will start on its own after that.
Will restart quickly rest of day and maybe the next day too.
Normal mileage, power, response.

Found power valves developed pinholes, tears. Happened more than once. Old parts, wear i guess.
Needed magnifying glass and good lighting to see that.
When pv was replaced, car started good again.
Maybe some siphoning action too. Clear filter usually is almost dry after a day or two.

Current carb is a different model Holley and does not do that. Touch key run. Bowl stays full.
No charcoal can bowl vent on that one.

Both carbs need coaxing for a minute or two when engine has been off overnight. As needed to keep running.
More in cold weather until engine warms up a bit and idles on its own.
No choke parts have been connected on the carbs.

[mustangnut]

It is a 4v carb. So what exactly would be the fix. Choke thermostat, can you buy just that? Thanks!

[mustangnut]

Thanks for the information. Fran

[mudgepondexpress]

Yes, readily available. To test it:

Car must be cold...like first thing in the morning cold.

1) Take off air cleaner lid (the choke is the flap at the top of the carb)
2) Step down on the throttle inside the cab, hold it down for a couple of seconds
3) get out and see if the flap is fully closed
4) if so the thermostat is probably OK and the linkage is sticky
5) If it is not, then get a new thermostat

There are orientation marks, make sure the new one matches the old one in position

Kenny

[mustangnut]

Where is the thermostat located. Your not talking about the thermostat that goes into the intake from the rad hose are you. Then not sure where it is located.

[gr79]

Carb spray cleaner will clean the choke linkage.

Have had the electric element inside the round black part of the choke burn out too.
The part with the wire to it. Easily replaced.
Note index (orientation) mark before removing.

Check the wire for power.
Had the wire burn up with the element.
Took out the alt charging wire to the regulator too.
Added inline fuse.
Finally took everything off. Had to pump when it worked anyway.

example of choke heater
https://www.rockauto.com/en/catalog/...+/+heater,6004

There may be a choke pull off. Know nothing about them
https://www.rockauto.com/en/catalog/...+pull+off,6000

[Walking-Tall]

Hands down I'll bet that the primary idle circuit is gummed up, if pumping the pi$$ out of it is required to get it going... the primary idle circuit should be providing all the air:fuel needed to get it started and idling... There are NUMEROUS dirt traps within the 4180's primary idle circuits... I would disassemble the front float bowl and metering block, and take out the primary main jets too, and "carb spray" and blow out the passages from the air bleeds (outer bleeds inside the choke shroud, and the bleeds out front of the choke shroud) in the main body and the passages within the metering block in either/both directions multiple times to make sure it's all clean and clear...

[mustangnut]

The flab was almost closed. Will get the new thermostat

[mustangnut]

Will take the carb. off to do what you are saying Going out now to get some carb. cleaner. Thanks again! Fran

[liv2roc]

back in 1984 I had my stock carb rebuilt by the dealer twice because of this. the gas is leaking out of the fuel bowl and you have to turn it over til it gets back full. time for a carb rebuild.