Carb float coating

[Oldtech]

Working on the Marvel on my D-35 which needs a lot of help. The cork float is actually in good shape but whatever they had for a coating is mostly off. Anyone have a good suggestion for a re-coat?  Im thinking maybe gas tank sealer but someone may have a better idea.

[JFranklin]

I think shellac was used originally. I used gas tank slushing compound on a cork float in a gas tank. It has held up over 10 years now.

[Dave39MD]

I have been using model airplane dope. I learned about it on an old outboard motor site. So far all is well.

 

Dave

[Robert Engle]

If you use gasoline with alcohol it will disolve the shellac.   Airplane dope, or superglue will work.  I prefer to replace the float with one carved from nytrophyle.  It's easy to work with.

 

Bob Engle

[Morgan Wright]

Some people use superglue. The point is to put something thin on, a thick coating will weigh the float down. Superglue is extremely thin and weightless. People say it works. I went with nitrophyl 

[carbking]

The original cork floats were coated with orange shellac. Modern fuel, with or without ethanol, will cut orange shellac like a hot knife cuts butter.

 

Have tried several coatings, including gas tank sealer, but have not found a single one that can be used successfully to re-coat the cork, once it has been in fuel.

 

We provide float pontoons from the modern closed-cellular nitraphyll (spelling) material in our rebuilding kits to replace the cork. The manufacturer states that since the material is "closed cellular", that the float does not need to be coated. I have NOT found this to be correct, depending on the local fuel.

 

We suggest that our customers coat the nitraphyll floats AFTER the old float arm is installed. Two materials that will work are: POR-15, and model airplane dope.

 

Jon.

[carbking]

Of course, if you guys get totally tired of trying to make the cork/foam floats work

 

Jon.

[edinmass]

After 25 years in the hobby..........and the same lesson learned multiple times......I never run cork in ANYTHING, except my wine bottles. Brass is all I use, no matter how many hours it takes me to make what I need.

[Mark Shaw]

On 9/2/2020 at 5:50 AM, carbking said:

The original cork floats were coated with orange shellac

I use either Red Coat tank sealer (because I have lots left over), or Krazy glue that is still working after many years.

This works on new cork floats but will fail on used floats due to gasoline contamination. 

Edited September 3, 2020 by Mark Shaw (see edit history)

[95Cardinal]

I have to agree with Jon and Ed.

I tried the superglue coating on a new cork float for my Cadillac. It worked for a few days, but that was it.

I then made a new arm that would retain a standard, cylindrical brass float. Problem solved.

[edinmass]

I had several types of sealer fail over the years......some in days, some in weeks, and one after a few years. I just got tired of dealing with it. All were Cadillac floats.........a word of caution, making and replacing a float can be ten times more work than you think, and cause all sorts of unexpected problems..........been there, done that.

[Oldtech]

Wow! Thanks for all the suggestions. That's what I needed to know. 

[Morgan Wright]

16 hours ago, edinmass said:

After 25 years in the hobby..........and the same lesson learned multiple times......I never run cork in ANYTHING, except my wine bottles. Brass is all I use, no matter how many hours it takes me to make what I need.

I agree with this. I use cork in my wine bottles, but not for very long.

[Brian_Heil]

Nytrophyl and be done. 
 

Carbking is the first person I have heard say he had an issue.