So what causes it? A lean condition?
What causes the idle jets to become clogged?
Engine is a '72 S with just over 100K on the clock. It doesn't smoke or, other than a few small oil seeps, have problems. Oil pressure and temp are good. I have been putting more miles on it recently, and it purrs along at 80mph for miles just fine. Bursts well over 100 with ease.
This is getting old. I don't want to pull up to a red light with the engine saying "spit"..... "spit"...
Last edited by dummkopf; 11-01-2018 at 03:26 PM.
72 911S Targa #0807 95+% German.
Paul Harrop 12.5% German.
Early S #2059
Usually comes down to adjustment procedure, jetting, or worn throttle shafts sucking air.
Early S Registry member #90
R Gruppe member #138
Fort Worth Tx.
Carb cleaner sprayed on the shafts would be a good check for that?Originally Posted by edmayo
So a spit is caused by an overly lean condition, right?
Thanks for the help. I just watched a video on adjustments. I have a synchrometer on the way.
Last edited by dummkopf; 11-01-2018 at 03:27 PM.
72 911S Targa #0807 95+% German.
Paul Harrop 12.5% German.
Early S #2059
Like Ed said above.
With my early car I chased spitting and wandering idle for years. Finally had the carb bodies rebuilt and the difference was amazing. Almost a set and forget kind of thing. Wasted way too much time trying to compensate for the loose throttle shafts.
Haasman
Registry #2489
R Gruppe #722
65 911 #302580
70 914-6 #9140431874
73 911s #9113300709
Just for grins open each idle fuel screw one full turn and see what that tells you
Last edited by edmayo; 10-26-2018 at 02:52 PM. Reason: add missing words
Early S Registry member #90
R Gruppe member #138
Fort Worth Tx.
4 out of the 6 will lose rpm. The other two, not so much.
Last edited by dummkopf; 11-01-2018 at 03:27 PM.
72 911S Targa #0807 95+% German.
Paul Harrop 12.5% German.
Early S #2059
What is your current adjustment procedure for equalizing air flow and idle mixture adjustment screws. Problem might be your adjustment procedure.
Early S Registry member #90
R Gruppe member #138
Fort Worth Tx.
I have not touched the air adjustment, just the idle screws. I adjust each of them one at a time until I get the most RPM. Then go back and do them again, adjusting the idle speed if necessary. As soon as When my synchrometer in, I will check and adjust the air screws if needed. I have a Haynes Weber manual for my procedure.
Took the car out yesterday for a drive. It idled okay at times but seemed to have a flat spot or surge at 3,300 or so. Now what? Above that or below it seemed fine. 4,000 it just purrs right along. Love the car, hate the carbs. Thanks again. I should have the synchrometer in early next week.
Last edited by dummkopf; 11-01-2018 at 03:28 PM.
72 911S Targa #0807 95+% German.
Paul Harrop 12.5% German.
Early S #2059
Don't overlook ignition timing re, that flat spot. After you turn out the idle screw for max RPM try turning the screw back in very slowly to see if the idle drops off again. You're looking for that sweet spot between too lean and too rich. What is your jetting, and what exhaust do you have, what distributor do you have and what is timing at idle. All of these can have an effect.
Early S Registry member #90
R Gruppe member #138
Fort Worth Tx.
I do need to check the timing. If it was that, it would be in the mechanical advance? Sticking? I just checked it and it is free. ?
No idea on the jetting. Stock 72 S 2.4 and stock exhaust.
It really amazes me how hard it will pull above 5K on the big end! Got close to 6K last time out on top. Speedo no worky. Me thinks 110 ish? Still climbing hard too!!!
I do have a GoPro....
72 911S Targa #0807 95+% German.
Paul Harrop 12.5% German.
Early S #2059
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