Too much gas !

[Bob NH]

I hope someone can give me a direction to go in here, I am at about my "wits end" . I'll start by saying I had very sooty Champion H10's plugs, I had seven NGK's on the shelf,put those in and left one champion till I could get to parts store for another. Have rebuilt four Strombergs and three Holly's. It is running very well except for seeping gas out of the top gasket on most of them, I went through all the Strombergs this AM to make sure the float setting was accurate and it is. Today after a short run around where I live, there appeared to be gas all over the fuel pump as well as carb. There is an electric pump and I thought I had it disconnected but with so many wires all the same color I am not sure if I got the right one or not ? My feeling is there is too much pressure forcing the float valve to open and I don't know how to check or slow it down ? Any thoughts will be greatly appreciated.

[Bored&Stroked]

Too much pressure is a real issue with Strombergs. You need to have a quality pressure regulator and gauge (not one of those cheap chrome ones with the dial on top). I'd get a low-pressure Holley version and a 1 - 10 lb fuel pressure gauge. You want a maximum of 2 PSI - or you'll flood the carbs.

Also, note that I usually need to adjust my pressure regulators (at least check them) given the time of year . . . most tend to fluctuate based on large outside temperature swings.

When selecting a pressure gauge - get one that is liquid filled and do NOT bring it into the passenger compartment - mount it right after the regulator. The last thing you want is a broken pressure line to throw gas all over you - and start you and the car on fire.

https://www.holley.com/products/fuel...arts/30-804QFT

[JayChicago]

Originally Posted by Bob NH

There is an electric pump and I thought I had it disconnected but with so many wires all the same color I am not sure if I got the right one or not ? My feeling is there is too much pressure forcing the float valve to open and I don't know how to check or slow it down ?

Another example of the added electric fuel pump causing more problems than it solved.

[drolston]

If you live south of the 49th parallel and want to drive in the summer using gas with alcohol blend, you are going to need that electric fuel pump to overcome vapor lock. I run a Mr. Gasket 42S, which is unrestricted when off, so the mechanical pump can pull through it. It puts out up to 3.5 psi, which may be still too much for the Stromberg carb.

I use the much distained el-cheapo chrome pressure regulator, which does a good job of limiting fuel pressure at the carb to 2.5 psi, and has held up fine for five years. The high quality ones are big and ugly.

I use a liquid filled pressure gauge, but beware. If they get hot, which they will under your hood, they build up internal pressure and will give you a false low or zero reading. To fix that, I took out the little rubber plug that seals in the liquid, and now it reads accurately, regardless of temperature. Just remember to plug the hole if you have to remove the gauge.

[Bob NH]

I might add that the truck came with the electric pump,I did not install it. My coupe also came with an electric pump and a toggle switch under the dash which works well to prime after sitting for some time.

[drolston]

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Originally Posted by Bob NH

I might add that the truck came with the electric pump,I did not install it. My coupe also came with an electric pump and a toggle switch under the dash which works well to prime after sitting for some time.

I think your next move is to get a pressure gauge on the carb side of the mechanical pump. Even with the electric pump switched off, the mechanical pump is capable of putting out too much pressure.

[Bob NH]

That's kinda what I had thought also, good to get others thoughts, thanks to all

[my4dv8]

Not true about electric pumps causing more problems than they are worth. If set up with correct size and pressure regulator 2 to 2 1/2 psi you will love it. Car sits for a bit , turn power on carb fills and starts instantly. Sure they can fail but so can any mechanical device.