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Thirsty Weber

870 views 3 replies 3 participants last post by  mcmud 
#1 ·
3 days ago after owning my jeep for 2 years i finally got the vaccuum lines from the EGR CTO valve and Evap Canister all plumbed up properly to my Weber 32/36 DGEV . Since doing so my Carb now idles at 1200 Rpm hot and the idle screw is no longer touching. when hot and idling in my garage if i slowly give the carb gas it will climb and stick at 1500 rpm even if i take my foot off the gas. Oddly enough if i kick the throttle hard and let off the gas my rpm drop to 500 rpm or in some cases the jeep stalls out and if i look under the hood at this time the idle screw is just barely coming in contact with my throttle lever. I thought maybe my throttle assembly had some play in it and thats why it idles so inconsistent but all the bolts are snug and if i tighten them anymore the pedal is horribly stiff. Lastly now the jeeps exhaust has been smelling like unburnt gas and gets half the MPG it did which was 10 previously. 5 mpg is to bad for even our jeeps espcially with my new lack of poor
:confused: :confused:
I suppose my questions are:

Why did hooking my vaccuum lines up effect my idle so much?

Why does the Weber jump in idle speed just by moving the pedal?

How do i correct my idle my Timing is Set to 9*BTDC should that be adjusted or is my Air/Fuel Ratio thrown off by my new hosing.

Does this sound like the Throttle linkage or should i be adjusting my air fuel ratio.

this is the how i hooked up my lines
 
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#3 ·
I don't have experience with the Weber, but with the Carter BBD. In general though, you could have more than one problem going on here. Check for vacuum leaks and linkage problems to start.

  • Make sure the choke isn't sticking. I've had this randomly cause high RPMs on my Carter. Kicking the skinny pedal hard would often unstick it.
  • I would make sure that the throttle cable/linkage isn't sticking before fiddling with the carb settings.
  • The vapor canister could be causing a vacuum leak and upping the RPMs. The purge valve can go bad, allowing the purge line to leak at idle. Try pinching off the purge line going to the carb and see if the idle changes. If it does change, then the vapor canister is bad. I had this be an issue with my Carter.
  • Check your idle mix settings using a vacuum gauge and make sure they are correct.
 
#4 ·
3 days ago after owning my jeep for 2 years i finally got the vaccuum lines from the EGR CTO valve and Evap Canister all plumbed up properly to my Weber 32/36 DGEV . Since doing so my Carb now idles at 1200 Rpm hot and the idle screw is no longer touching. when hot and idling in my garage if i slowly give the carb gas it will climb and stick at 1500 rpm even if i take my foot off the gas. Oddly enough if i kick the throttle hard and let off the gas my rpm drop to 500 rpm or in some cases the jeep stalls out and if i look under the hood at this time the idle screw is just barely coming in contact with my throttle lever. I thought maybe my throttle assembly had some play in it and thats why it idles so inconsistent but all the bolts are snug and if i tighten them anymore the pedal is horribly stiff. Lastly now the jeeps exhaust has been smelling like unburnt gas and gets half the MPG it did which was 10 previously. 5 mpg is to bad for even our jeeps espcially with my new lack of poor
:confused: :confused:
I suppose my questions are:

Why did hooking my vaccuum lines up effect my idle so much?

Why does the Weber jump in idle speed just by moving the pedal?
There is no reason to believe that connecting the tubing has caused a fluctuation in idle speed nor efficiency of the carb performance.

There is linkage or plate binding going on. Either a tube is restricting movement back to the curb idle speed setting, possibly the accelerator rods are in need of re-adjustment, or the throttle lever nut is overtightened drawing the throttle rod and plate against the bore. One or more, of these is the cause.

How do i correct my idle my Timing is Set to 9*BTDC should that be adjusted or is my Air/Fuel Ratio thrown off by my new hosing.

Does this sound like the Throttle linkage or should i be adjusting my air fuel ratio.
That diagram was drawn for a member that insisted on using 'S' ported vacuum for spark advance. You should consider moving that tube over to the manifold source. Your distributor was designed to use this source.

In order to set the idle speed screw you must maintain the choke plates open, while you open and close the throttle, since in this case there is the suspicion that binding is occurring I suggest you use the throttle lever itself to assure that the plate is closed once opened.

If you need a guide to help with dialing in the Weber give a shout.
 
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