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Thu Feb 17, 2005 9:24 am

On going problems....

I changed out accelerator pump on my carb, jet that feeds from the top works great, but when I put the acclerator wide open, it does not seem to feed much fuel down inside the carb, but I hear plenty of air. After checking distributor, changing accelerator pump, changing spark plugs, cleaning up carb (not rebuilding yet) replacing a starter I am determined its either the pump, carb or a vaccum leak somewhere.

I want to check they fuel pump before I rebuild the carb, how can I check it to see if it is working properly? Not to get ahead of myself, but if it is the pump is it better and very difficult to run an electircal fuel pump?

thank you

Thu Feb 17, 2005 9:41 am

Go to Sears and buy a $15 -$20 pressure guage. It comes with hoses and fittings to put it in-line between fuel pump and carb. It will tell you how much fuel pressure your pump is delivering to the carb. You'll need to compare that to the specs for your particular carb.

Thu Feb 17, 2005 10:03 am

What you are saying is disconnect the inline hose to fuel pump and hook up a hand vacum pump (I have one I bought to bleed my brakes with) and I leave the hose from fuel pump to breather on carb (with inline fuel filter) connected?

Thu Feb 17, 2005 10:27 am

Quote:
To carb

     |
     |
     |____ To el-cheapo sears pressure gauge
     |
     |
     |

From fuel pump

You put a fitting to el-cheapo sears pressure gauge so you can see the pressure as you rev the engine.

Thu Feb 17, 2005 12:50 pm

jackstraw wrote: I want to check they fuel pump before I rebuild the carb, how can I check it to see if it is working properly? Not to get ahead of myself, but if it is the pump is it better and very difficult to run an electircal fuel pump?

you will need a friend, a small container. Have a friend sit in the driver's seat and wait for you to say "start it". Take the fuel line off the carb (the one going from the fuel pump to the carb. Take the end off the carb and place it in the container. have your freind start the car for at least five cranks... the gas should come out at a steady rate. if so then your stock fuel pump is working fine. If not you could have a bad pump that needs a rebuild or you need to check your gas tank and fuel lines for blockage. Not hard to do...take off the fuel line that comes from the gas tank and into the fuel pump. Take it off at the fuel pump. Have a freind blow into the line (dont' suck, blow) and you take off the gas cap and listen for air bubbles.... if you hear them then your gas line is ok....check the filter in the gas tank that may be clogged to. More than likely it is your fuel pump. Buy a basilian one for now or a kit to rebuild your german one.

Thu Feb 17, 2005 1:25 pm

If your doin this remove the coil wire completely and have the fire extinguisher right there and a hose there too!!

Just a little splash of gas on the dizzy when it is sparkin and there is goin to be a big-un and you cant run fast enough to get anythin to get it out quick enough. One second is too long for damage!! :!:

Thu Feb 17, 2005 2:11 pm

I hope abdon's diagram helps. The guage needs to be AFTER the fuel pump to register the pressure, and then the line still goes from the guage into the carb so that you can start and run the engine.

Maybe this will help--

1) disconnect fuel line from carb and connect that line to one side of the top of a "T" fitting (should have come with the pump/guage.)

2) take another piece of fuel line (scrap piece a few inches long) and run it from the other side of the "T" fitting and to the carb

3) attach the guage to the bottom of the "T" with another scrap of fuel line.

4) fire up engine and give it a few seconds to level out on the guage.

Good luck!

Thu Feb 17, 2005 7:36 pm

Yup really getting pissed now :?

Ok so maybe I am stupid

Fuel lines were clean, replaced all rubber hoses bought a new fuel pump and I must have reversed the hoses? Pump is a brazilain made but it is not just like the one I took off, this one has 1 valve coming straight up off the top and one on the side. I put the hose coming from fuel tank on the top of the pump and the one to carb on the side. Is this the correct way? I now have NO gas moving to carb!!!

Thu Feb 17, 2005 9:46 pm

Not sure about your specific pump, but it should have either a paper with a diagram showing inlet and outlet, and/or an arrow on or near one of the connection tubes showing direction of flow. Might be harder to see once it is installed, but give it a shot.

OR, try switching the hoses on the pump...I think the worst it would do is try to suck air out of the carb and into the tank, but someone might know more...

Good luck-you're not stupid, just learning.