wont idle

Old 02-13-2010, 05:59 PM
  #11  
DirkaDirka
Senior Member
RACING JUNKIE
 
DirkaDirka's Avatar
 
Join Date: Jul 2009
Location: Clarksville, TN
Posts: 1,954
Default

I did a quick and easy fix and got an edelbrock and installed it. It was just going on a SBC 400 with mild cam that I just putt around town with so I didnt really need a top of the line carb.
DirkaDirka is offline  
Old 02-13-2010, 06:28 PM
  #12  
Scooterz
Senior Member
RACING JUNKIE
 
Join Date: Mar 2006
Location: EUGENE,OR.
Posts: 3,408
Default

Originally Posted by Tod74
BOWHAY, what is your vaccume at idle with the trans in gear? 6.5 is the power valve that comes in them when new, but if you are below that with your vaccume it could be opening up.

Again, the main jets will not make it run rich at an idle if everything is set right...
X2. Had this expierence too. Had to measure vac @ idle & figure altitude for mine too. Has anyone mentined floats/level etc...? What about a stuck needle & seat.
Scooterz is offline  
Old 02-13-2010, 06:46 PM
  #13  
bbchevy
Senior Member
RACING JUNKIE
 
Join Date: Mar 2003
Location: Fountain,MICHIGAN
Posts: 856
Default ?

Have you ever CHECKED the Float Levels?
Thats the Only way that Fuel would just be Dumping though the Sec.I would be Willing to Bet the Back Float Level is To High or the Float is Stuck from the Needle and Seat,NOT Seated?
Bet,you take out the Level Set Screw and Gas POURS all over the Place!!!
EDELBROKE-if your going to mess with Junk like that?You would be BETTER Off with a Rotenchester(QUADRAJET)!
Later
G 8)
bbchevy is offline  
Old 02-13-2010, 07:59 PM
  #14  
Tod74
Senior Member
RACING JUNKIE
 
Join Date: Sep 2007
Posts: 4,143
Default

Originally Posted by bowhay
ok so the secondary idea makes sence
well heres what was done before all this stuff happened, i had a 650 on the truck, wanted a 750 and a friend had a main body and base plate from one so i took my blocks and bowls and put them on this 750 body, i took out the flaps to clean them up and when i put them back in there was a visible gap around the secondary flaps, so i think what may be happening is that fuel is just runnin through the secondaries cus the flaps are open a lil bit

and due to the fact that i have a lopey cam could tht make it to where i need a different valve?
X2 on the float level...

ALSO it is normal to see some day light sround the throtle blades when you hold it up and lok at them...you need to make sure they are centered good since you had them out.

Yes the camshaft is what will determine the amount of vaccume you have,which will dictate which Powervalve you need....If it is blown or open it will be EXTREMELY rich...

Since you had it apart I am thinking an internal leak or as was mentioned the float level..but if the float level was good before you took it apart,it will be the same since all you did was transfer the bowls from one carb to the next. jmo

Also, can you get a response from the mixture screws? If you turn the screws in and the engine doesn't seem to change,or you can't kill it, then you have too much of the idle transfer slot exposed and are pulling fuel through the main circuit.
Tod74 is offline  
Old 02-13-2010, 11:19 PM
  #15  
bowhay
Senior Member
EXPERT BUILDER
Thread Starter
 
Join Date: Nov 2008
Posts: 263
Default

floats and needles are fine and no there is no response from the mixture screws
bowhay is offline  
Old 02-14-2010, 05:18 AM
  #16  
Tod74
Senior Member
RACING JUNKIE
 
Join Date: Sep 2007
Posts: 4,143
Default

Originally Posted by bowhay
floats and needles are fine and no there is no response from the mixture screws
No response from the screws means you are on the main circuit..or there is some kind of leak pulling fuel. If it was running ok but rich I would say you had the speed screw turned in too far exposing the transfer slot..but since you had it apart and it won't idle I'd take it back apart.
Tod74 is offline  
Old 02-14-2010, 06:21 AM
  #17  
DirkaDirka
Senior Member
RACING JUNKIE
 
DirkaDirka's Avatar
 
Join Date: Jul 2009
Location: Clarksville, TN
Posts: 1,954
Default

Originally Posted by Tod74
Originally Posted by bowhay
floats and needles are fine and no there is no response from the mixture screws
No response from the screws means you are on the main circuit..or there is some kind of leak pulling fuel. If it was running ok but rich I would say you had the speed screw turned in too far exposing the transfer slot..but since you had it apart and it won't idle I'd take it back apart.

Thats what I was trying to tell him. On the Holley I had it didnt matter what you were doing with the idle screws it was still running rich and thats when it was noticed that the rear the secondaries were just pissing fuel down the carb. I think I just couldnt explain it good enough. Thats for explaining it better than I did.
DirkaDirka is offline  
Old 02-14-2010, 06:37 AM
  #18  
Tod74
Senior Member
RACING JUNKIE
 
Join Date: Sep 2007
Posts: 4,143
Default

I had one that the accelerator pump cam wasn't adjusted correctly and as the engine shook it was bouncing the pump arm enough to dribble fuel. Too hard to say without being there.
Tod74 is offline  
Old 02-14-2010, 08:19 AM
  #19  
bowhay
Senior Member
EXPERT BUILDER
Thread Starter
 
Join Date: Nov 2008
Posts: 263
Default

ok so if i were using the wrong power valve and too big jets i kno it would be way rich, but would tht make it smoke? if u stand by the exhaust ur eyes start to water from the gas
also is it at all posible to put the rear blades in the front and fronts in the rear?
just tryin to think of anything
bowhay is offline  
Old 02-14-2010, 08:30 AM
  #20  
Scooterz
Senior Member
RACING JUNKIE
 
Join Date: Mar 2006
Location: EUGENE,OR.
Posts: 3,408
Default

Never even heard of that one before... troubleshooting that one would be like a needle in a haystack senario... did even know it could happen. Have had a carb pull extra fuel through trnasfer slots like Tod was saying... even drilled extra vac holes in secondaries. I swear, every time I think I know the basics about carbs now, something new comes around.
Scooterz is offline  

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service