Another Carb problem

[amc401]

Ok need a little more help!
When I got the car it wouldn’t run except on starter fluid. I made a make shift gravity fed fuel tank and the car ran great. Then I went and replaced all the fuel lines to and from the tank. Put on a new fuel filter of the same kind, and then replaced the fuel pump ( it was bad.) with one from auto zone that was stated for the car. Car started right up!! But didn’t run as great as it did with the gravity fed tank. It starts hard now and doesn’t want to stay running? And some times backfires. I am still new to carburetors, so not to sure if the carb needs rebuilding, or what… . Thanks and also I have a Weaber DGAV. And the car did sit for about 1.5 years before I got it.

[baz]

which car you have might help

but i would be looking to the pick up in the tank as a starter if its a gt
theres a filter mesh that clogs up and gives fuel flow problems , a search for tank sock or just sock should find the threads on it
if its the other models i dont know if they have it but removing the fuel cap and feed line to pump then blowing back into tank with air line might give you a partial clean to get you going

if it runs well with a feeder tank i cant see it being the carb

[bigjim5551212]

if the carb was sitting. then you have to be aware that the idle passages might be plugged. check all these things

pump squirter, sqirts
auxiliary venturi holes are pointing down
the float is not stuck
the float bowl is not full of crud


Its time to take the carburetor apart and discover the internal workings.

[tomking]

which car you have might help

but i would be looking to the pick up in the tank as a starter if its a gt
theres a filter mesh that clogs up and gives fuel flow problems , a search for tank sock or just sock should find the threads on it
if its the other models i dont know if they have it but removing the fuel cap and feed line to pump then blowing back into tank with air line might give you a partial clean to get you going

if it runs well with a feeder tank i cant see it being the carb

Listen to what Baz said. If it ran well from the gravity tank and then did not with the new fuel pump from the stock fuel tank, look at the sock first.

[amc401]

Thanks, I'll check the sock. And sorry, it's an Opel GT>

[MICAH1]

And here is my two cents, sense we are all talking about checking and changing filters. Unscrew and flush out the filter in the front of the carburetor bowl... Then adjust the air/fuel mixture screw on your weber, and set ignition timing.

These six post should clear up all or most of the problems.

[baz]

And here is my two cents, sense we are all talking about checking and changing filters. Unscrew and flush out the filter in the front of the carburetor bowl... Then adjust the air/fuel mixture screw on your weber, and set ignition timing.

These six post should clear up all or most of the problems.

but then why would it run ok with a gravity feed from an can and not from the tank ??? almost has to be the sock blocked with crud

[MICAH1]

Put on a new fuel filter of the same kind, and then replaced the fuel pump ( it was bad.) with one from auto zone that was stated for the car. Car started right up!! But didn’t run as great as it did with the gravity fed tank. It starts hard now and doesn’t want to stay running? And some times backfires. I am still new to carburetors, so not to sure if the carb needs rebuilding, or what… . Thanks and also I have a Weaber DGAV. And the car did sit for about 1.5 years before I got it.

Baz,
You may well be correct, but the backfire condition could be fuel starvation. Could be the sock, the carb filter, or......... a lean carb. He has enough suggestions to hopefully make the correction.

[baz]

this is why i think the tank sock

from the first post

I made a make shift gravity fed fuel tank and the car ran great.

any thing else that is not a problem when fed from the gravity tank can be ignored

[Dennis Texas]

Ok need a little more help!
When I got the car it wouldn’t run except on starter fluid. I made a make shift gravity fed fuel tank and the car ran great. Then I went and replaced all the fuel lines to and from the tank. Put on a new fuel filter of the same kind, and then replaced the fuel pump ( it was bad.) with one from auto zone that was stated for the car. Car started right up!! But didn’t run as great as it did with the gravity fed tank. It starts hard now and doesn’t want to stay running? And some times backfires. I am still new to carburetors, so not to sure if the carb needs rebuilding, or what… . Thanks and also I have a Weaber DGAV. And the car did sit for about 1.5 years before I got it.

Heres the skinny : take gas cap off remove line off of suction from tank if you do not see a solid stream of petrol you have tank issues. If you see consistent flow from tank then blow the lines out and change filter you say you have a new pump so lets rule that out for now continuing on up I know weber you can look down and see the actual petrol in the carb reservoir You have to have a good stream of petrol to carb once you establish that, timing and carb adjustments along with various vacuum leaks ( I usually block all the vacuum except the distributor ones and set up like that) when restored with booster and any other vacuum driven devices you have and it acts weird or inconsistent I isolate line by line until I find the culprit. Just another opinion

[amc401]

OK. I pulled the line off the gas tank, and a steady stream of fuel came out. I then ran a line from the pump to a gas can with fresh new gas. Same problem. I replaced all the rubber fuel lines to and from the tank. I did NOT how ever replace the plastic ones. Its does have a new fuel filter on it. Could it be that now since the carb has pressure to it, it is getting to much fuel?

[MICAH1]

AMC401,
Are there any Opel owners close to you, and have you reached out to any of them on this site??? At this point, getting more qualified eyes on this issue may bring a quicker solution to your problem than us going back and forth in this forum. What type of fuel pump did you replace the old one with??

(1) I think you need to check the tank sock and either confirm it as the problem source, or scratch it off the list as a possible.

(2) Remove the plastic line under the car and run a 5/8 rubber gas line from the metal lead on fuel tank, to the fuel pump, and up to the metal line that bends in front of the motor.

If we work from the back to the front, you will at least know that the fuel route from the tank to the carb is clear..

[Redskinsjbs]

AMC401,
Are there any Opel owners close to you, and have you reached out to any of them on this site??? At this point, getting more qualified eyes on this issue may bring a quicker solution to your problem than us going back and forth in this forum. What type of fuel pump did you replace the old one with??

(1) I think you need to check the tank sock and either confirm it as the problem source, or scratch it off the list as a possible.

(2) Remove the plastic line under the car and run a 5/8 rubber gas line from the metal lead on fuel tank, to the fuel pump, and up to the metal line that bends in front of the motor.

If we work from the back to the front, you will at least know that the fuel route from the tank to the carb is clear..

I agree with Thomas. Working back to front will ensure that you know what the deal is with the fuel system through and through, no surprises. I have found a few on my car and it is always a good feeling to have caught the problem before it makes one...

and you kick yourself when you find a problem and you know that you should have checked for it

But yea,

-Check the sock,
-check the line / replace it
-check the pump
-check the line from the pump to the filter (and any filters in between)
-check the line from the filter to the carb
-check the filter in the carb
-check the jets...all of them

This should all take a couple hours at most,... so take two and call us in the morning!!!

[charlie1966]

Here is my 2 cent(Euro cent by the way!) but I believe that some inline fuel filters are directional. If i remember correctly, it should be an obvious marking if it is and it will only take e few seconds to check if they are not marked.

[Dennis Texas]

Could it be that now since the carb has pressure to it, it is getting to much fuel?

I think what may be happening is you have crud in the carburetor and the pump putting pressure on it forcing crud into the inlet needle assembly with the float, when you gravity feed it it just flows slowly instead of being forced into the carb. You should be able to look down the top of the carburetor and see the gas inside the bowl, level is hard to detect, but presence of gas in bowl you will be able to see. The top of carburetor has several screws holding it on and the choke linkage will need to be unhooked and you should be able to lift the top off and expose the bowl and float area for a better idea of its condition. If you think it is too much fuel, after you start it you can put a pair of vise grips and crimp the inlet fuel line closed and see if it's too much fuel, you can check that easily enough without opening the carb up..