carb boiling over
 

ok my fordbarn friends here is my delema. when the weather is cool her i dont have a problem. my 8ba runs like a top. when summer comes and it warms up i have a problem where once my car hit 180-190 deg and i stop at a light when i take off it seems ok but then stumbles. it will sometimes even die like its out of gas. i believe this to be a heat problem with the gas boiling or vaporizing. i inclosed a pic of the side of my carb (brown color) that wasnt there when the weather is cool. at this point im not running a hood on my 51 and it still does it. any ideas on if this is the problem and what i can do to remedy it. i have even put an electric pump to help out when it happens but it doesnt seem to help. normally i run the mechanical pump. thanks

Re: carb boiling over
 

I would be inclined to check that the float and needle are not sticking in hot conditions. You might try blocking the heat risers with pennys at the block opening under the manifold.

Re: carb boiling over
 

ill look into that. can anyone show me a picture of exactly what to block off with the pennys. thanks

Re: carb boiling over
 

Here is a picture to show where the pennys go.

Re: carb boiling over
 

41ford1 ...........................
Blocking the heat risers will also make your dual exhausts sound better. It will keep the two sides from "crossing over".
The last ones that I installed, pennies were too small, and nickels fit exactly into the gasket, so it cost an extra $.08.
MIKE :)

Re: carb boiling over
 

I made a heat spacer under the carbs on my 40

Re: carb boiling over
 

My 32 was boiling out over the weekend in 95 degree heat on a tour, ran fine under a load but going down long steep grades could smell gas when you let off of it. First time it has ever done that. I add about a quart of kerosene to a tank of gas which helps a lot and the back up elec. pump is there for emerg. I noticed when it was parked Sat you could hear the gas siz. and that is with extra gaskets under the carb.

Re: carb boiling over
 

Take 2- 20 or 22 gauge pieces of sheet metal about 1" wide and 2-1/2"s long, bend a tab up about 1/2"" long up at a 90 on one end of the metal.This tab will allow you to hold the metal to install it. Loosen the manifold and slip the long end in over the heat riser holes and tighten. This way you can easly remove them. It sounds like the float is sinking and the needle valve is open. A sticky needle valve will also leave to much gas in the bowl. Check and make sure the float don't have a hole in it, this lets gas inside of the float and it sinks letting the needle valve open. G.M.

Re: carb boiling over
 

I hope Ken CT will wade in, but he may still be on the road. I have the same brown stain and another problem of the bowl draining after a couple of days sitting. He advised that it is the power valve leaking. Remember we now have "alky" added to our fuels, and it is lighter, and may also be attacking the rubber in the seats and the power valve. ByronW.

Re: carb boiling over
 

If the power valve was leaking it will run rich and the plugs will be sooty. A leaking power valve will allow the fuel to run in the engine from where it is located. G.M.

Re: carb boiling over
 

this is a carb that i had kenct rebuild for me a few years back.. that brown mark wasnt there until after the incident the other day. the carb runs flawlessly other than that. now when i put the pennys there should i just give em a small dab of silicone to keep them in place while i mount the intake?

Re: carb boiling over
 

I pcket some steel wool down the heat riser hole on top of the intake manifold just under the carberator gasket. Then a good mixture of JB weld was added on top and pressed down on top of the steel wool. Waited until it set up and then I put a gasket from Ken/Ct. on top with no power valve hole in it. It all worked for me. Chet

Re: carb boiling over
 

If you had a backfire it will blow out your power valve. also check your fuel pump pressure, shouldn't be more than 3 1/2lbs.

Re: carb boiling over
 

If you do the penny thing, make sure you use pennys made before 1982. They are copper. After 1982 pennys contain a lot of zinc and will deteriorate.

Re: carb boiling over
 

I'm far from a guru on these things but here's what I would do. I would at the very least make sure you reduce your fuel pressure to 1 1/2 lbs, clean things off, and see what happens. You may also be getting some fuel vapor lock - is your gas cap vented? This new gas may have loosened up some junk in your gas tank - does your fuel pump bowl have any particles in it? Look dirty? If so, I would put a good, removeable gas filter just after your gas tank or perhaps on the f-wall before it enters your fuel pump. I would also clean things out as well.

Finally, because of todays new gas it has more alcohol and it may be evaporating to a certain extent - after all, you live in NV where it's pretty hot. I would put 1 oz or so of Marvel Mystery oil in the gas at every fill up just to give yourself some top side lubrication and to slow the derteriorization of your old carb's components. Don't go crazy with this stuff - I usually put a dfash in or so at fill up time. There are some automatic oiler units that are out there - I know Vic has installed one on his 39 - that can be installed down the road if you feel so inclined.

This new gas also attacks the old rubber gas lines - I would switch out all the old lines with fuel injection lines. Your old lines could be collapsing/deteriorating and sending debris to your carb.

Now, ain't old cars fun? For myself, I would not have it any other way ....

Re: carb boiling over
 

Jason,that gasket deal only works when useing a 94 type carb with a manifold made for a 34-36 mtr,some have a extra hole for heat.You can try the penny deal but doing so is kind of rough till the motor completely warms up.Get rid of the teflon tape you have like on the fuel pump line.It WILL get into the carb.N/G. ken ct.