302 wont idle when its rainny

[427]

I know this isnt a bump, but I have a 72 bronco with a 302 and it wont idle when its rainning. I know this sounds crazy but when its not rainning it runs great. Where should I look for a problem at? Any help appreciated. Thanks,Brian.

[fordman]

distibutor mihgt be getting water into it. it has to be electrical like that.

[427]

I checked the disrtbutor cap and it wasnt wet, i did spray it with wd 40 anyhow to be safe.Thanks for the help.

[70_F100]

Carburetor icing.

Mine does it BADDDDDDDDDDDDDDDD!!!!!!!!!!

[427]

What causes the carb to ice? How can it be stopped?

[Ranchero50]

Make sure it has the original air cleaner on with the heat stove going from the exhaust manifold up to the air cleaner for the icing. I also had a condensor in the distributor go bad and do that years ago when it rained (in Orlando Fl of all places)

Jamie

[91Bear]

My first car was a 1966 VW bug. It wouldn't start when it was rainy, drizzly, misty, foggy or just really humid. Gotta be the distributor.

[fastEdsel]

I'd vote for carb ice as well. We can pick it up in our carburated airplanes and we have a carb heat button we can pull, much like a choke cable, to direct heat from a muff around the muffler directly into the intake box of the carb. Depending on how much ice has built up it can take a couple minutes to melt off but it can be a killer not only in airplanes, but if your carb freezes on a busy highway, the outcome could be a rear end wreck from a stall. Ice is formed when low pressure, high humidity air is forced through the venturi effect on the carb. It is compressed, then rapidly released across the throttle plates which form ice on the plates, closing off the proper air/fuel mixture and a rough running/flooding engine is the outcome. You can never stop a carb from icing in low temp, high humidity conditions. Just make sure your heat riser from the exhaust manifold is working and some of these engines had a plate under the carb that the engine coolant ran through, heating up the base of the carb and thus trying to prevent icing. It has always been a problem for all the car manufacturers until they went to fuel injection. What I do if the ice starts to form and the engine is not quite warm and I can hear the engine start to flood is just turn it off for a couple minutes. The heat from the engine rises to the carb, melts off the ice and am good to go again. Just for something to do sometime when that happens again, remove your aircleaner and just look at the sides of the carb and it will be frosty. A good stiff shot of gasline antifreeze sometimes helps melt off the ice as well. Hope that is some help.

[70_F100]

Couldn't have said it better myself...