Does the thermostat have anything to do with fuel mixture. I had read that a common cause of "running rich" was a bad thermostat. Here's how I interpreted it. Does this sound right to anyone?

The engine uses a rich mixture when it is cold. As the engine warms up, the thermostat somehow notifies the carb that the temperature is rising so it can lean out the fuel mixture. A bad thermostat will not let the carb know that temperatures are up. The engine thinks it is cold all the time so it runs rich like it would during cold start up.

What do you think? Can a bad thermostat cause a rich condition?

Thanks in advance. Steve

Steve H. '82 CJ8 258. TR upgrade. Borgeson steering shaft.

The thermostat controls the engine temp, but it's a little sending unit threaded into the block that senses the temp. ,and relays the info. If the thermostat is stuck open the engine won't warm-up.

Just a little ole Cj, That likes to pick on snipers : )

[img]/wwwthreads_images/icons/tongue.gif[/img] On today's emission-regulated engines, many of the functions are keyed to engine water temperature. Sensors in the water jacket change the spark, control the EGR, and even the transmission. The best thing to do is stay with the temps that were designed into the engine. Otherwise you will have to do a lot of changing and get rid of a lot of temp-dependent sensor-controlled stuff.[img]/wwwthreads_images/icons/crazy.gif[/img]

CJDave
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