I have touched on this in other posts but have been chasing several problems at once and believe my power valve is the last big issue. I rebuilt my Mc2100 with a GP Sorensen kit that had an unmarked power valve. I have been doing a lot of fine tuning and it runs very well with the exception of the strong fuel smell at idle. I believe the power valve in the kit is not the appropriate size for a stock 258. Just curious what size power valves have worked for others on the same setup. Thanks for any info.
I am at 2500 feet and for now run a 8.5 pv and 46 jets in my motorcraft 2150... I wish there was a database somewhere that gave the general guidelines at to what is best at what altitudes... That would be very handy!
It only hurts while you're breathing..
The PO removed the CAT. Running manifold with 8 degrees initial advance. The fumes will saturate clothing and wilt anything green. It's strong even condering there is no CAT. Plugs are a nice dark brown.
Check the power valve to make sure the diaphragm didn't rupture. If ok check the accelerator pump to make sure diaphragm didn't tear. Can you screw in the idle screws without dropping the idle speed. Are the jets the same as when it ran correctly?
It runs great other than the stink at idle. I have only ran #48 jets, but it's my understanding that jet size doesn't effect the idle. The accel pump is good. If I start to screw in the idle screws the vacuum guage will not be steady and it will begin to run bad.
I've read in a holley book that if jet sizes can effect idle mixture but only if the sizes are way off base. If the jeep ran ok before and something just happened (that's why I asked, incase you just changed jets), I was just trying to rule out. If you screw in the mixture and rpms start dropping and runs irratic your not to far off on the mixture. Is it a new carb to the jeep. If I remember right (god help us), they made the 2100 in different sizes. If it's a new carb to the jeep could it be a higher cfm carb, which could run a richer idle mixture.