New Gas Boiling

[Floridian Flathead]

Hello:
Has anyone had problems with alcohol fuel boiling in the carb? I have been told that placing a plate, metal or phenolic, between carb and manifold will eliminate this problem. Would anyone like to elaborate on this?
Rick

[gmc1941]

Look at the back threads about a week ago or less.

[FL&WVMIKE]

Floridian Flathead ..................
A better bet is to block off your heat risers. This is the exhaust that goes into the intake manifold. You car will take a little longer to warm up, but that's not too big a problem here in Florida.
For decades, people have been blocking this off with one penny, one each side.
It will make your dual exhaust sound better too !
MIKE

[G.M.]

FL Flat Head, I'm just about winding up my testing of fuel boiling in 85 plus outside temperatures. We have had about 85 temperatures for the last 3 days and I have driven about 75 mile in the afternoon each day. Here's a list of temperatures I got today. At start= fuel tank 78, fuel pressure 3 3/4 lbs. Drove 35 miles and checked temperatures. Left head 181, right head 183, carb bowl 106, intake manifold at base of carb141, fuel inlet pump 116, fuel pump 117, gas tank 99.

Stopped for 15 minutes and returned differant route 40 miles.
Arrived back at shop. And taested as soon as stopped.

Fuel pressure 1 3/4 lbs.,Left head 168, right head 169 going into the wind comming home runs cooler, fuel pump inlet 119, fuel pump 122, carb bowl 107, carb base 115, intake where carb bolts to 140, Intake itself 157, fire wall bottom 140, fire wall top 119, fuel tank 103.
oil pressure at idle 15 and 40 at speed with 15/40 Cummins valvoline blue diesel oil.

The fuel line is clear of the exhaust and no heat from the pipes transfering to the tank. Heat to tank comming from hot roads. Fuel line removed from fire wall clamp insullated with pipe insulation from below fire wall to pump. The 125 + heat from the rear of the engine heats the fire wall and the steel line clamped to the fire wall heats the fuel line to 125 if clamped. Without insulation the 125 heat gets the flex line brass fittings to 125. The fuel line is 2"s from the fire wall. The carb has a vented 1/2" phenolic spacer from Bob Shewman or Gadgiteer between the carb and the intake manifold. .020 SS tabs with 1/4" holes between intake manifold and top of gasket reduceing but not eliminating the carb heating. The only problem area now is the 160 degrees on the intake manifold about 5/8" below the fuel pump. Jambed foam insulation somewhat under the fuel pump and had less heat on the pump today than the last 2 days. I'm going to get Gadgiteer to make me 1" phenolic spacer for under the fuel pump stand to insulate the pump from block heat and give me 1 3/4" clearance under the pump. Will need to make the push rod 1" longer. This should take care of all the problems with the 10% gas mix. When this gas gets close to 125 you start to get problems. G.M.`

[David J]

You won't have this problem if you stop using the el-cheapo gas . Non-oxygenated gas isn't that much more & cures this problem . The pump will say "for classic cars , motorcycles" etc and some will say "non-oxygenated" on the pump . Easy to find in WI or MN . I see it is here in FL also .

[Cecil/WV]

Originally Posted by David J

You won't have this problem if you stop using the el-cheapo gas . Non-oxygenated gas isn't that much more & cures this problem . The pump will say "for classic cars , motorcycles" etc and some will say "non-oxygenated" on the pump . Easy to find in WI or MN . I see it is here in FL also .

I haven't seen this in the east. Might be OK if you drive in a localized area, but what about when you are on an extended tour and by the way, where can you buy el cheapo gas at today's prices?

[Joe AZ]

Originally Posted by David J

You won't have this problem if you stop using the el-cheapo gas . Non-oxygenated gas isn't that much more & cures this problem . The pump will say "for classic cars , motorcycles" etc and some will say "non-oxygenated" on the pump . Easy to find in WI or MN . I see it is here in FL also .

I agree........I moved from Minnesota, where it was readily available, to Arizona. Not so easy to find non-oxy fuel here. I wish I could.
Joe

[Bill S]

Have never seen gas like that. El Cheap gas here in So. Cal is $4.39 to $4.49. some places that are remote over $5.00.

[TomO]

Gas with alcohol has been sold in CA and IL since the early 1990's. All blends in IL have alcohol in them.

We have temps in the high 90's and have not had a problem with the gas 'Boiling".

If you think that your gas is 'boiling', the least expensive and best cure is to use an electric fuel pump with a return line 'Teed' just before the carburetor. This way the temperature of the fuel in the carburetor is always close to the tank temperature. The return line can be fuel injector hose, but I would use a copper coated steel line for the supply and leave the stock fuel pump in place for backup. The return line can be inserted into the fuel filler hose (38 and up) to make it easier to return to stock.

IMHO the phenolic spacers are another 'profit enhancer' like the turbine plate that fits under the carburetor to supposedly give more horsepower and increase mileage. Moving the carburetor venturi, changes the dynamics of the fuel flow from the carburetor to the intake valves.

Before investing in any changes from stock, I would make sure that the carburetor is working correctly. I set the float level 1/16" lower than specs when the fuel contains Ethanol. This does not affect performance if the fuel pump is working correctly and the fuel line from the tank is in good shape. The power valve must be correct for the 94 carburetor and be correctly installed. Make sure that your fuel pump is performing according to the Ford specs (10" vacuum on the input and 2.5lbs on the output)

[David J]

This stuff is EASY to find in MN & WI & is also here in FL . If it isn't in your area then you probably can't use it with any degree of practicality but the poster of this thread is in FL & it is definately available here . "el-cheapo" is a reference to my opinion of this ethanol garbage , not that the price is cheap . In WI the good stuff is $0.20 more a gallon at the station by my house . There are other threads on this & it seems odd to me that this isn't available "in the east" . Isn't FL in the east ? I'm heading back to WI monday & I will be going through GA , TN , KY , OH , IN , IL on my way home & I will keep an eye open for { and ask about } this stuff . On the tour thing a couple gas cans should get you past the gaps in supply but again , this isn't hard to find where I'm at .

Originally Posted by Cecil/WV

I haven't seen this in the east. Might be OK if you drive in a localized area, but what about when you are on an extended tour and by the way, where can you buy el cheapo gas at today's prices?