DistributorVacuum

[Powerstroked]

Anybody know how much vacuum there is suppose to be at the distributor when the engine is at idle? I have 10in. at an idle. The problem is, after setting timing with vacuum hose plugged and idle speed adjusted to spec's, when i hook up vac line my idle speed increase's and will not adjust down to spec. Any idea's? Thanks

[Jeep Craze]

Hey John, Were pretty close in area how's it going? Ism't it too cold to work on your rig(unless you got a garage). Anyway at idle (warm idel)your vacuum to the dist. shoudl be 0". What must be happening is your CTO isn't switching completely. You should have a cto on the thermostat housing that regulates manifold vacuum when cold and when warm it switches to ported. Just to make sure it isn't the carb, unhook the ported line were it comes form the carb and check it there w/ the gauge. It shoudl be 0 at idle and increase steadily as the throttle is rotated. If that is 0 at idel then your problem is w/ the CTO. If it isn't 0 at idel then your problem is your carb. Which could be addressed a few different ways. Craig

[Georgia Mike]

IIRC,the vaccume advance hose should be connected at a port above the baseplate of the carb. This will ensure the increase in vaccume occurs at higher than idle RPM's. Make sure it's connected to the proper port before doing anything else. I could be WAY off,though. It's been a while since I've messed with that stuff. :D

[ March 03, 2003, 06:55 PM: Message edited by: Georgia Mike ]

[Jeep Craze]

Hey john, an edit to my first post. The CTO on the therm. housing controls the idle when over 220degree. The top one(I think) should go to a CTO over by the coil. That should possibly have 5 ports on it.Either one could possibly be the culprit if you determine that the carb ported vac is functioning properly. Craig