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Jack -

Mine has a few problems that I could either blame on the timing or the "re-do" I did on the carbs (first porject on the car, ever, so the rare cnce exist that I could hav emessed it up like the other 99).

Question -- how do you know if the bowls are leaking? Smell of gas or ???

Also - could this be a cause of "run on" ? Could be timing - it jsut sounds too good to be that ?

Tx-

George Zeck
 
Run on is timing, no question, back it off a degree at a time. It will quit.

If the gowls are leaking on an H1 carb the fuel runs out the carbs or down the mix adjustment nut. Yes you will smell gas as well.
 
Jeff (Bugeye58)
Since you are the only one of us who doesn't need to do this I will ask you to do a favor for all of us.
You say that you have a good gauge (that measures in inches of water)-- will you measure the output pressure of a pump and then do the clear hose set-up and tell us what a 2 PSI (whatever that is in "water) pump would read in feet of fuel?
By the way- for everyone- my measurements were "number of inches above the pump" not "number of inches above the ground", it is only about 12" difference but we just need to be consistant.
Bill
PS: I tested a "Fawcet" pump today and it went 90" (7'6") above the pump.
 
The density conversion that I put in my previous post is pretty spot on unless I've forgot everything from my fluid flow classes. I did get the gasoline density from an unsourced internet page but it seems fairly close to what it should be. The height that you get in the tube from the inlet port of the carb to the top of the liquid can be directly converted into psi felt at the needle of your carb (not necessarily at the pump). Just because a pump can lift the fluid 90" above its outlet port doesn't mean that the pressure will be the same everywhere in the tube. It will vary as the height of the load changes in relation to the height of the fluid. Every 37.5" of gas above the inlet of your carb is 1psi of pressure.
JC
 
gauge pressure does not use density in its measurement. Wouldnt it be easier to just buy a correct range gauge. My vacuum/fuel pump tester goes from 1 to 10 psi. Its not for fuel injected cars.
 
Bill, I'll have to rig up a test bench, but I don't see any problem there. The main snag is time, right now.
I'm on a chaotic work schedule at the moment.
Jeff
 
Pressure is simply a measure of force exerted on a specific area. Gauge pressure is a reading that has been corrected for atmospheric pressure. The conventional measurement is pounds force per square inch (psi) but no matter what units you chose (kg/cm2, mPa, inches of mercury, inches of water, etc.) it is easy to convert it from one form to another. Bill used a tube to measure the height that his pump was capable of pushing a liquid. The two forces that would limit the pumps ability to pump it to the heavens would be the friction of the tubing in regards to the liquid (this has to do with what the tube is made of, what size it is, how many bends are in it and the characteristics of the fluid being pumped) and the weight of the liquid in the tube or the force that this weight is placing on the mechanism in the pump to make it go. This weight is a component of mass, the volume it occupies, and the gravitational force. The density of pure water is 1000 kg/cubic meters hence it is the standard to which most other things are measured. The density of gasoline is 737.22kg/cubic meters. What this means to most people is that 27.7 inches of gas will exert 74% as much force at the bottom of a column as water will. Guess I'm just ranting at this point but what I'm trying to say is Bill has just rigged up one of the most accurate test stands that can be made when dealing with low pressure (unless you spend a few thousand on a 12" dial high accuracy gauge). Sorry for going off on the tirade here.
JC
 
Hay, I have found it most intresting, carry on.
 
JC
YES-now it makes sense and correlates pretty well, I just was having a heck of a time trying to remember just how to start. Thanks!
Now with that in mind I have found:
My Lucas pump puts out 3.6PSI
Honda pump- 3.2PSI
Old Gold pump (Bap-Geon brand!!) 2.6 PSI
Gold Fawcet pump 2.4 PSI
All usable and without a regulator!
Bill
 
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