VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 1931 Carburetor corrosion

HI all,

We have finally gotten our 31 special sedan up and running. We have been working on fine tuning the engine to get it purring. It has been running for a couple months without any major issues. This week when we pulled it out, it started without any issue but it quickly sputtered and died. Upon further inspection of the carburetor we found 2 problems. the float had a hole in it and was full of gas. The other problem which has left our heads scratching is that there was a significant amount of corrosion in the float bowl. We suspect it is the gas we are using. Does anyone know what could be causing this corrosion and how to prevent it from happening?

Clarification please: Is the "corrosion" eating away the brass bowl? or is it corrosion "sediment" which is from the other (softer) parts of the carburetor body?

And one other thing to look at... sometimes a lot of dirt-type sediment ends up in this bowl. It might be mixing with a small amount of corrosion. You need to look closely (on a white paper towel) and see if it's ALL corrosion or a mix of that and dirt.

Now, one last thought, if you have a lot of corrosion in the bowl, what does the rest of the carb body look like? Is it visibly pitted?

Bill B

Thanks for responding. The corrosion is not eating away the brass bowl. It is sediment from the corrosion from the body of the carb. Also, the corrosion only occurred on the body that is submerged in the gas in the brass bowl. No other visible corrosion throughout the rest of the carb. When we looked at the material in the bowl it did appear to be a mix of sediment and corrosive material. There does not appear to be any visible pitting on the carb or bowl yet.

One other question I forgot to ask in my last post was about gas type. We used gas with ethanol in it. Does that make a difference. I know back when these cars were made ethanol was not something they put in gas.

I have run gas with ethanol for years in my 37 and 52 with no problems.

The ethanol in the gasoline attracts water. The water is what is the main cause of corrosion. So the answer to your question "Does that make a difference." is DEFINITELY. Finding gas without ethanol will help. There are gasoline additive companies that claim their miracle juice will protect our cars. That remains to be determined.

One point is if there is no gasoline with ethanol in the carburetor the attracted water can't cause a problem.

Thank you all very much. You continue to be an amazing resource for newbies like my dad and I.