I really appriciate all the help ive gotten from you guys here on the carb board in getting my 79 MCM4 to run well, that being said...

I got the mixture to give me a stable good idle from less than 0 degrees out to over 50 degrees (stupid connectucut winters) but it wants to die when it starts raining hard out or even snowing vigorously.

I would imagine this is a humidity problem and BTW I know the ignition is ok cause I checked all that.

question is would humidity make the idle mixture lean or rich...

I would think that increasing the moisture content of the air would leave less room for vaporizing fuel and therefore make it lean but what do I know...

thanks

 

high humidity makes it rich.
water vapor displaces oxygen in the air, but fuel metering remains the same.... therefore rich.

You might want to hook up a heat-stove to feed warm air to the carb for winter since you live so far north. The idle circuits can freeze up sometimes in winter.
Make sure the air-bleeds for the idle circuit are clean too.

 

awesome -- just what I wanted to know thanks!