20 struggles to idle when first started

[berrett]

i have an 80 truck with a 20r that i have been working on. i put a reman 22r carb, but now when i start the truck up after sitting for a couple hours it doesn't want to idle well. i will chug down to about 500 rpm and then die out, after a minute or so of holding my foot on the gas and then driving a little way, it will idle just fine. it runs great when driving (but sometimes kinda "hiccups" around 1500 rpm. the idle problem doesn't happen everytime, but most of the time. any ideas on what could cause this?

 

[WristPin]

any old carburator that has been removed and turned upside down has a high probability of disloging gunk and clogging up somthing else.
i know you say you have a reman carb, but im just throwin that out there.

are you sure the rebuild job was done right?

use a vacuum gauge to measure the inches of mercury pulled at the intake manifold.
a measurment of this will tell you many important thing about whats going on in the engine.

if every thing is the way it should be, at any RPM speed, ( give the engine time to replenish vacuum) the vacuum gauge should read 17-22 inches of Hg.

do the test and report back your findings. i will interpet them for you.

also, check your EGR valve operation. a shop with a smoke tester can hook up to this and check for leaks.

also make sure your fuel filter is clean.

 

[berrett]

any old carburator that has been removed and turned upside down has a high probability of disloging gunk and clogging up somthing else.
i know you say you have a reman carb, but im just throwin that out there.

are you sure the rebuild job was done right?

use a vacuum gauge to measure the inches of mercury pulled at the intake manifold.
a measurment of this will tell you many important thing about whats going on in the engine.

if every thing is the way it should be, at any RPM speed, ( give the engine time to replenish vacuum) the vacuum gauge should read 17-22 inches of Hg.

do the test and report back your findings. i will interpet them for you.

also, check your EGR valve operation. a shop with a smoke tester can hook up to this and check for leaks.

also make sure your fuel filter is clean.

the fuel filter is new, and the carb was rebuilt by Holley. i will try to check the vacuum