CIS Cold Start (I Searched)

[jcwolff]

Hello-
I have a 73.5 T. I had some oil leaks fixed over the winter. Pretty much wherever oil can leak, it did. I used a reputable mechanic in town. I picked it up about a month ago and drove it a bit. I brought it back with some idle and startup issues. A month later I have it back. They told me they checked everything and it is all in good working order. The few things I'm still not happy about they say is just the way these cis engines are. Well after reading endless posts about this topic here I know they aren't very good at tuning the cis. When I fire up the car cold, I turn the key twice and it stumbles and putters for about ten seconds then starts up. When I drive it warm or cold it surges between 2000 and 3000rpm. It idles warm at about 1100-1200. I think I can iron out these problems myself between the idle, mixture, and a new tank of gas. The weird thing that I ask you folks is when I start it up cold, the rpms go to 6000. This happened once, and now I know when its coughing to get started I drop the throttle half way so it starts at 3000. I can then push the throttle 75 percent down and it idles perfectly at 1200. At any point in time I pull up the throttle I can get it to almost redline. My mechanic says that it's normal. I don't think so. I have read that it is supposed to be between 3500 and 3800. Is this just a simple adjustment on the hand throttle screw, or is this a bigger problem? Any help is appreciated. I will probably start tinkering with it this weekend with a new tank of gas. Thanks.

[Jim Sims]

It appears the linkage and CSV microswitch are out of adjustment.
The adjustment for a 1973.5T is covered in the Haynes 911 manual.

Here is start of a chain of threads you may find helpful or at least informative:

Cold Starting a 73.5 with CIS

[lusso]

Jim,
I did a hand throttle search and this is what I found. I greatly appreciate your info. I was able to adjust the "control piece"(broken pieces lying in the cavity) until new piece(ordered today) arrive.
Thanks
David

[jcwolff]

Thanks for the link. I have that one saved in my vast cis article library already. Well I thought this would be an easy adjustment, but I have more going on I think. When I look at my hand throttle, the clamp is pushed as far back as possible. I cannot lower the hand throttle rpms using this. There must be something wrong with the linkage adjustment in the back by the throttle body. I did notice that the microswitch is activated when I barely lift up the throttle. I also tried unplugging the microswitch to see how it affected it. The car started a lot rougher but I still got it started with two turns of the key. No affect on the idle. I am reluctant to start tinkering with the turnbuckles as that will no doubt screw up my accelerator and idle. Any help is much appreciated.

[lusso]

Jim,
New piece arrived. It took a little less than an hour to install. It is nice to have the hand throttle work properly.
Thanks,
David