Flooding problems

[joz1973GT]

Well I have done my reading but cannot find an answer. Here is the sit rep, I have a 73 GT and the factory fuel pump would hardly pump any fuel at all, but if you kept the revs 1300 rpm or higher it would run for a little bit and then die out. It will run if the revs are over 2000 on its own. So I installed a eletric pump as I have read in these threads. I was wondering if the fuel pump I got was too much. It pumps at 4-6 PSI but i did not take out the factory pump hoping it would help to regulate the fuel pressure. But after all is install and wired up I started the engine and it ran very rough and when I shut it down the was a pool of fuel on the secondary butterfly. So at this point I am thinking of scrapping the entire factory fuel system and setting it up as I have done cars with one fuel line to the pump and one from there to the carb. I love this car but it is proving to be difficult at times. Thank you so much for the help

[hrcollinsjr]

Originally Posted by joz1973GT Well I have done my reading but cannot find an answer. Here is the set rep, I have a 73 GT and the factory fuel pump would hardly pump any fuel at all, but if you kept the revs 1300 rpm or higher it would run for a little bit and then die out. It will run if the revs are over 2000 on its own. So I installed a eletric pump as I have read in these threads. I was wondering if the fuel pump I got was too much. It pumps at 4-6 PSI but i did not take out the factory pump hoping it would help to regulate the fuel pressure. But after all is install and wired up I started the engine and it ran very rough and when I shut it down the was a pool of fuel on the secondary butterfly. So at this point I am thinking of scraping the entire factory fuel system and setting it up as I have done cars with one fuel line to the pump and one from there to the carb. I love this car but it is proving to be difficult at times. Thank you so much for the help

3.5PSI is pretty much max. Are you sure you don't have a vacuum leak? I would bypass the factory pump if I was running an electric pump.

Harold

[joz1973GT]

So I guess I should get a fuel pressure regulator. I checked for a leak but could not find one, but I will check again. Is there a common place where the leaks may be. Now if I get a weber would I need to keep the fuel pressure down as well?

[hrcollinsjr]

Originally Posted by joz1973GT So I guess I should get a fuel pressure regulator. I checked for a leak but could not find one, but I will check again. Is there a common place where the leaks may be. Now if I get a weber would I need to keep the fuel pressure down as well?

Solex carbs are notorious for warped bases because of the two piece design and people overtightening them. Weber's are much simpler to deal with and generally offer better performance.

The fuel pressure requirements are the same for both carbs. So, yes you will need a regulator if you keep the current electric fuel pump.

Harold

[West Coast GT]

A. I'd guess that you would be better off installing a new low-pressure electric pump rather than adding a fuel pressure regulator.

B. Purchase a fuel pump "blank" from Opel GT Source, and remove the old mechanical fuel pump as it's only function at this point is to provide you with one more potential failure point. The blank is inexpensive.

C. The most common vacuum leaks for the 1.9 engine are:

• Base of carb, especially the Solex, which tends to warp easily
• Intake manifold to head
• Brake and distributor (both lines) connections on the base of the intake manifold just below the carb
• Distributor vacuum advance & retard lines at the distributor
• Brake booster vacuum line connections at the in-line check valve and brake booster canister

[joz1973GT]

Thank you that does explain a lot. If it was not so hot here I would be working on it tonight. What do you think about the idea of getting rid of the factory fuel lines and making it a single line?

[hrcollinsjr]

Originally Posted by joz1973GT Thank you that does explain a lot. If it was not so hot here I would be working on it tonight. What do you think about the idea of getting rid of the factory fuel lines and making it a single line?

Since you're complaining about the heat I would recommend keeping the return line. It's there to help prevent vapor lock.

Harold

[timemachine]

Harold's comments sound right on to me but I'd first troubleshoot the factory setup before reengineering anything, which is just as likely to get you into tougher problems to diagnose.

If you have constant fuel flow also make sure the fuel chamber float is not stuck or sunk, which is another common problem with the Solex, though folks like me and others have had continued success with them and haven't changed out to a Weber. The problem most commonly presents in fuel dump a couple minutes after a hot engine is shut down.

Jim

[tekenaar]

Originally Posted by hrcollinsjr 3.5PSI is pretty much max. Are you sure you don't have a vacuum leak? I would bypass the factory pump if I was running an electric pump. Harold

. . . 'cause you definitely don't need the electric pump just to get fuel to the mechanical one! FSM warns to block off fuel line from tank when removing it from the fuel pump, because pump is below tank and will drain the entire tank if this is not done!

[joz1973GT]

Thank you for the advise. I will be ordering the fuel pressure regulator soon and get that installed. I am guessing that I have to get under the car to disconnect the factory fuel pump? Cause I cannot see a way to get to it from the top. I am just really wanting to drive this car. I have never driven one and I bought this one for my dad but he is not able to work on it and I think it will be a blast to drive. Oh and I am trying to find intake manifolds for it so I can do sidedrafts on it but I am learning that they are very rare and hard to find, any thoughts?