1936 Chrysler Ace carburetor iceing

[Mitch29]

Hi there.I have just bought a 1929 Custom built Pilot House cruiser. I am having problems with the updraft Zeinth carberater iceing.I have already built a system to bring warm air from the top of the manifold to the intake of the carb. This does help a little, and brings the inlet temperature to about 95 F. But still ices in as little as 5 min. Any help on information would be appreciated.
Mitch

 

[puddle jumper]

Re: 1936 Chrysler Ace carburetor iceing

Only two things come to mind. Either you live in a very humid climate or your gas has absorbed a bunch of water "yes gas can absorb water". I would install a water/fuel separator and route the hot air tube more direct into the carb. In the summer you will have to change the hot air tube away from the carb.
Good luck

 

[rodbolt]

Re: 1936 Chrysler Ace carburetor iceing

I have also built a few custom hot water systems for the updraft carb/intake.
use 1/4" or so coper tubing, wrap it as tightly as you can without kinking around the carb base and intake.
tap the water inlet into the discharge of the thermostat and route the the discharge either back into the exhaust or overboard.
the old updrafts had a legacy of icing even in automobiles.

 

[steelespike]

Re: 1936 Chrysler Ace carburetor iceing

I don't think the old Aces have a thermostat.You could temper the intake water with a bypass from the discharge side with a valve to control the amount of warm water you can regulate operating temp.You also might try adjusting the mixture screws.I believe slightly richer may help.I've operated 2 aces,a number of Chris Craft sixes,couple a Grays ,and a Lycoming with a 2 barrel updraft.Only had icing problems on a tiny 4 cylinder Brennan and was going to try that idea about wrapping carb and flange but never did.No other icing problems even running into the 40s in the fall.You might consider a thinner gasket between carb and manifold.Sometimes there is an exhaust hot spot right where exhaust leaves the manifold you might get some warm air there.