Leaky fuel pump and carb all at once!

[douggreif]

Hi guys, I have a 67 GTX with a 440 that really likes higher octane fuel. I am currently running 100 low lead aviation fuel. The car runs great with this fuel but I am now dealing with a leaky fuel pump and a leaky carb. Does this fuel lead to these problems (I have been told this) or is it just part of owning an older car? If it is the fuel are there fuel pumps and carb parts designed to deal with it? Any help would be great!!!

 

[bigmanjbmopar]

Were are the leaks? have you checked the fitting to make sure they are secure?

What about the carb, is it leaking from the inlet or the base gasket? or bowl gasket?

Fuel pumps have a gasket between them and the block as does the carb base. Have you replaced these once already and they leak right away?

 

[douggreif]

The leak on the carb is the accel pump. The pump looks to be leaking around the flange not at the block. I am really interested to know if the 100 Aviation fuel is the problem. The leaks I can fix just want to avoid more if possible Thanks

 

[1969CoronetR/T]

Why not use unleaded 93 octane?

 

[1966Coronet]

I think your problem does come from the aviation fuel as Avgas is less dense than gasoline it will sip thru gaskets where regular 93 automotive gas won't. There's a special gasket material made by Permatex that you can use in conjunction with your original gaskets to prevent this. It's Permatex Aviation Form-A-Gasket No.3. its brushable, non hardning. Give it a try and let us know how it went.

"Avgas is less dense than most racing gasolines. Instead of weighing about 6.1 to 6.3 pounds per gallon like racing gasoline, it weighs 5.8 to 5.9 pounds per gallon."

 

[1966Coronet]

Im assuming your car is not street legal, just so you know, Avgas contains lead, and as of 1996 its use on street-cars has been ban. Fines can go as high as $25,000. Just some FYI. Good luck with the leaks!

 

[1969CoronetR/T]

Most racing fuel has lead and I see cars pull up to the pump and put it directy into their car instead of a container. I do not think the police are worried about this in my area.