TheSamba.com :: View topic - Need some Fuel pump / Carburetor help please

Sun Feb 23, 2014 6:00 pm

engine: 1835. don't know cam size
dual kadrons
009 distributer
checked timing a couple times
adjusted valves all to .006
faucet electronic fuel pump and cheapy empi pressure regulator

Problem. Runs good(except lower rpms-ive been told that's due to running single barrel carbs)
When I cruise down the road it does good, I can shift from 4th to 3rd at about 60, get on it up to about 75(4000 RPM or so), shift to forth, then it starts to sputter and back fire like it's running out of fuel. if I shift down even worse at higher rpm. IF I put in neutral and let at idle for a half a minute or even less, then I can get on it again for a minute then it starts to sputter again. if I cruise at lower rmps, it does okay.

So I rerouted the fuel line(it's a little longer and has a few more bends in it than stock) I know longer and more bends = more resistance and harder to push fuel through.
I'm wondering if that's the problem, or could it be my fuel pump can't keep up or???
any opions and help would be great. thanks

Sun Feb 23, 2014 6:15 pm

I was taught to NOT use a regulator with an electric pump. Instead, find a pump that puts out exactly what your carbs need. Many people still do it, but I don't.

I originally had a Carter pump when I had my Webers and 1904. I used the fancy Italian regulator, because I wanted to keep it in use. It actually made complications at higher rpms. A couple guys in Utah recommended I remove it. I did, and it solved my issues.

Im NOT saying this is your problem, but it may be a possibility. Personally, I would experiment with that, just for kicks. Also verify float settings.

Also, I would verify the jetting that is in there. Has the engine always done this or is it a new problem?

Sun Feb 23, 2014 6:53 pm

I'll remove the regulator. It never did this before I rerouted my fuel lines. I did have the regulator on there before, but I never ran it like that either. This is the first I really ran it that much. I will bypass the regulator and see if that fixes the problem. I just heard that you want to run one to prevent too much pressure?? But if the fuel pump can only put out 2-3 psi at most? Sucks cause it's a lot to test.

Sun Feb 23, 2014 8:21 pm

If it's the facet fuel pump that's rectangle in shape it's not going to put out enough pressure to need a regulator would be my guess.
You said "cheapy" regulator, I'd say that you hit the nail on the head. If it's adjustable then it really needs to meet the trash can. IMO those things are junk. Throw the regulator to the side, hook the lines back up, and drive it again. It could be float adjustment but if it didn't do it before i'd say not. It also helps to mount the fuel pump as close to the gas tank as possible, it does better pushing fuel than it does pulling fuel a long way from the tank.
At least you know the problem, lack of fuel. It can only be so many things so you'll figure it out.
Good Luck!

Mon Feb 24, 2014 1:55 am

are your fuel lines far enough from hot stuff (i.e. exhaust)?

gas tank vent working?

is your electric fuel pump pushing fuel rather than pulling it?

is the fuel system clean?

Sun Mar 02, 2014 7:14 pm

So my filter was a bit nasty. I redid my fuel line route (I was able to elimate 4 bends in the tubing) and bypassed my regulator. Unfortunately I did not have time to test drive it today. I will tomorrow. Hopefully all is well. But I've read that those faucet fuel pumps don't put out enough pressure anyways.
If this does not work what is a good fuel pump and regulator if needed? Thanks

Sun Mar 02, 2014 7:18 pm

Silly question..............but is your fuel pump is mounted in the rear? or front by the tank?

Sun Mar 02, 2014 8:40 pm

It's located directly under tank. I have a petcock, fuel filter, then a 180 degree bend with copper tubing, then fuel pump, the. It goes into the tunnel. Where it comes out in the back I have another filter to catch any crap in my fuel lines. Then it goes up into carbs.