<VV> mystery fuel leak, need help

[Ramon Rodriguez III]

Alright, I think I figured it out and it's a strange one!!  I noticed it
looks nasty, and perhaps a little damp inside the bore for the longer carb
mount stud.


So here goes....  the carb top gasket is leaking to the stud hole.  While
the car is running the leak and fuel pump actually fill up the air space
inside the stud bore right to the top gasket level.  Now I shut the car off
and that tube is full of fuel, but it can't escape because the carb base
gasket has it sealed up at the bottom.  So now we have a tower of gas in
there and it slowly leaks past the threads at the base of the stud and onto
the engine tin.  The "leak" via the threads at the stud base is very slow,
so it takes a long time for that tube of fuel full up to the top gasket to
drain this way.  That would explain why it looks like I have a fresh gas
leak despite the fuel level in the carb being FAR too low and (the fuel
pump hasn't run in over a week) to have recently leaked out of the body
gasket or fuel line =)

I'm just about positive this is what was happening, only thing that would
ruin my diagnosis is if the (long outboard) carb mount stud is in a blind
hole... cant get under the carb mount flange to check it because there
isn't enough clearance.


Ray "Grymm" Rodriguez III



On Fri, Mar 16, 2012 at 2:46 PM, Ramon Rodriguez III <corvairgrymm at gmail.com
> wrote:

> I have a terrible feeling that I'm missing something obvious but I really
> need to get this fixed.
>
> A week or more ago I started smelling gas when walking past the 63 coupe.
>  I opened the engine lid and noticed it was wet behind (toward rear of the
> car) the passenger side carb (the car is facing slightly uphill so the
> wetness is on the downhill side).  I looked around and felt the fuel line
> and got no moisture on my finger at the inlet/filter nut area.  I figured
> the leak was probably due to my having taken the carb apart a couple times
> without replacing the (only a few months old) gasket.
>
> Now the car has been sitting without being started for over a week and it
> is still very wet in the same place which I find odd.  Today I decided I
> needed the car back on the road so I took the top of the carb off and found
> the fuel level inside the bowls to be just barely below the main jet.....
> far lower than the top gasket!
>
> Also of note, I can't see any real stain trail from anywhere on the carb
> down to the puddle of gasoline.  It looks like (but impossible I think?)
> the fuel is leaking out at the base of the carb.  Again, it is important to
> remember that the car has not been cranked or started for over a week...
> possibly closer to two weeks.
>
> Thanks for any help!
>
> --
> Ray "Grymm" Rodriguez III
> Lake Ariel, PA
> 1966 Corsa 140 coupe (summer daily driver)
> 1965 Corsa 180 coupe (under construction)
> 1965 Corsa 140 (Fitched) coupe (under construction)
> 1963 Monza PG coupe (daily driver)
> 1962 Monza PG coupe body (to rebody the rusty 63)
> Seeking a dirt cheap Spyder coupe
>  _______________________________________________
>