carb problem

[smprider112]

Ok so the carb on my truck, well Uglychevys old truck...77 jimmy...has been acting up. when it starts up it keeps wanting to die out if you dont give it gas. basically if I keep the Rpms above 1500 it runs awesome, step on the throttle and its still smooth, but if I let it idle down it will die.
I have played with the idle and the airscrews are set to 1 1/2 out but it still wont run properly...now he thinks its the accelerator pump cuz hes had it go bad a few times(damn edelbrocks!!or It'llbrakes) anyways does this sound like a pump that has developed a vaccuum leak? I have also checked all the vaccuum lines too...also the distributor was kinda loose, I was able to turn it, could this be the problem too? Im not too knowledgable in the carb dept. so I need all the help I can get on this one.
also will using a propane torch (no flame) work to detect a vaccuum leak at the pump?

 

[pauly383]

Edelbrock Edelbrock , or Edelbrock Quadrajet ? And yes timing is off now if you turned it . Did it hold an idle before or after you turned the distributor ? I would turn the air screws out 2 turns to start with , adjust the timing and idle speed until it doesn't stall , adjust timing with light to stock specs , then fine tune the carb to best idle on the air screws , set idle speed again , re check timing on the light . The accelerator pump is just that , for acceleration , idle is not really going to be affected by it . For kicks and giggles , replace the base gasket ( what intake you have ? does it match the carb , or need adapter ? ) and double check the vacuum hoses , especially the pcv and brake connections /forums/images/graemlins/k5.gif

 

[smprider112]

ya its not the quadrajet....as for the timing, I turned after it had shut off (actually ran outta gas) so I wasnt able to see if that did anything...I'll have to look at the vaccuum lines again, is the torch idea a good way or not??
also for the timing, I guess cuz its got an aftermarket timing cover it doesnt have the timing tab /forums/images/graemlins/blush.gif so I cant check that....but Rob (Uglychevy) has just informed me there is a tab available that bolts right up, So I'll have to get that b4 I can check the timing with a light.

 

[pauly383]

You need to do something for the timing tab , or get a good ear for it . You will need to put some good gas in it ( too bad you ran it dry , not so good as dirt settles to bottom of tank ) and move distributor until it fires up easily , and replace that timing tab so you can get it set . Also since it sounds like you are starting out experience wise , don't use a torch , base gaskets and rubber vacuum lines are dirt cheap , just replace them for pennies per foot and have no vacuum leaks /forums/images/graemlins/k5.gif

 

[smprider112]

cool I'll have to just get new lines and see where Im at then too...I was thinkin after you mentioned the dirt/crap from running it outta gas, could that cause this problem>? maybe since it was so low on gas? knowing my luck prolly not /forums/images/graemlins/whistling.gif /forums/images/graemlins/dunno.gif

 

[diesel4me]

Also check and make sure the secondary butterflies are closing all the way at idle--if they stick open a little it will stall out at idle,due to the large amount of air rushing in and leaning th mixture out. /forums/images/graemlins/crazy.gif

 

[smprider112]

actually it looks like the butterfly is sticking open a lil...how can I remedy this? it doesnt feel gummed up or anything (actually the carb looks almost new /forums/images/graemlins/yikes.gif)

 

[pauly383]

Double check the linkages for any binding , or something hanging it up . If your model has a choke with a secondary lockout , check that too for the same /forums/images/graemlins/k5.gif

 

[TrcksR4ME]

[ QUOTE ]
cool I'll have to just get new lines and see where Im at then too...I was thinkin after you mentioned the dirt/crap from running it outta gas, could that cause this problem>? maybe since it was so low on gas? knowing my luck prolly not /forums/images/graemlins/whistling.gif /forums/images/graemlins/dunno.gif

[/ QUOTE ]

Did it start acting up after it ran out of gas? The fuel filter could be glogged up not letting enough gas through at idle. I have also used cheap gas in mine a few times and had it do the same thing. What you describe though sounds like a vacuum leak or glogged fuel filter. What I did when checking for vacuum leaks was plug off everything on the carb except what you need to run, like dist. If it runs ok then, then go about checking each of the other things one by one.

 

[smprider112]

/forums/images/graemlins/whistling.gif /forums/images/graemlins/whistling.gif /forums/images/graemlins/whistling.gif Ok...I AM A DUMBASS!! I just filled it up with fresh gas, fired it up, adjusted the idle...and now it runs just fine!! I still need to fine tune the carb since it feels a lil hessitant but it's idling just fine and I even got to drive the beast around a lil /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif thanks for all the help guys!! I know if it starts doing it again tho, what to look out for! /forums/images/graemlins/thumb.gif





cant believe it....the damned gas was the prob /forums/images/graemlins/doah.gif /forums/images/graemlins/doah.gif at least I did get lucky I guess tho! /forums/images/graemlins/peace.gif /forums/images/graemlins/woot.gif