PDA

View Full Version : stock carb tuning?

JeepWagon
04-15-2003, 11:30 PM
I have the stock Motorcraft 2bbl on my 83 Wagoneer. When I go off-road it will not idle. The last two trips I drove to the wheeling spots, at least 2 hrs. each trip, and it ran fine. As soon as I got there, after driving access roads my truck would not idle. Seems to be running too slow. Adjusting the idle setting does not help. The last time out I opened the top of the carb and raised the float level some and that seemed to help, but the idle was still low all day. After I drove a while towards home the truck ran fine.

Any thoughts on what I should be looking at? Is there an off-road needle and seat for the Motorcraft, is it necessary? I've checked for vaccum leaks and replaced some questionable lines, same result. I recently rebuilt the carb and it seems to work fine on the road.

Any input would be apreciated.

Thanks,

Andy B
SLINKY
04-15-2003, 11:58 PM
Andy where are you wheeling, higher elevations? upstate PA.
JeepWagon
04-16-2003, 12:03 AM
Upstate? I went to Paragon and then out to Big Dogs, near Winchester VA. I'm sure the elevation was higher, but is it enough of a change to make a difference?
Fish
04-16-2003, 12:47 AM
Do you have a high altitude compensator on the back of the carb?
SLINKY
04-16-2003, 02:16 AM
i'm not sure, but i wanted to check that out and make sure the guru's here knew it. yes paragon is upstate in the mountains of PA
JeepWagon
04-16-2003, 06:44 AM
OK, what is the high altitude compensator?
Fish
04-16-2003, 09:22 AM
JeepWagon,
the high altitude compensator supplies additional air to the intake system to lean the ari/fuel mixture at high altitudes. There is a spring loaded valvue that reacts to atmospheric pressure adjusting the air allowed into the carb.

The HAC is located at the back of the carb that the screw driver is touching in the pic below.

I have what sounds like the same problem and I am pretty sure the culprit if the HAC. Good luck, and hopefully someone a whole lot smarter than me will chime in with some info. Additionally, try searches on this site under 2150, carb, carburetor...

http://www.fullsizejeeps.com/jeeps/files/Parts-Junkyards/fish05a.jpg