80 911SC Targa Air/Fuel Mixture

bzk103 · 07-07-2007, 09:14 AM

I'm trying to adjust the air fuel mixture on my 1980 911SC. There is an adjustment screw between the fuel distributor and the sensor plate, according to "101 Projects for your 911." I'm having a tough time locating this, does anyone have any advice or tricks to locating this adjustment screw. I know my vehicle is running rich and I want to lean it out, hopefully that will bring my idle RPM down a bit also.
Thanks

fred cook · fred cook's Garage

There is a small hole that a metric allen wrench fits thru to access the adjustment screw. I think the wrench size is 3mm. You will need a fairly long allen wrench to reach the screw. Once you have made the adjustment, remove the wrench before trying to rev up the engine. If I remember correctly, you will need to turn the screw in a counter clockwise direction to lean the mixture. Try to make your adjustments in very small increments. An eighth of a turn will make a significant change. You really need an exhaust analyser to do the job correctly.

holtjv · 07-07-2007, 01:34 PM

bzk, get an angled mirror and strong light--you'll see the hole only. There are lots of good threads on this subject, search something like, "fuel air mixture adjust".

Good luck, you'll find more info than you'll need. J

walt · walt's Garage

Use a 3mm allen wrench in the hole where you see #14.
http://www.pelicanparts.com/PartsLookup/HTML/911_USA_78_83_KATALOG/107-00-Frame4.htm

bzk103 · 07-10-2007, 11:53 AM

Thanks a lot, all of your suggestions worked, I found the adjustment screw, I didn't make any adjustments until I can get a hold of my mechanics CO2 exhaust detector. That way I can make the proper adjustments. I have one other problem, I just drove for close to an hour and now I can't get my car to restart. I'm going to open the line on my fuel accumulator to see if it leaks, but at the same time I wonder if the mixture being too rich can also cause this problem??