Sergio Santos Posted April 25, 2020 Share Posted April 25, 2020 Hello ! anybody can give me a info about in this issue on my Buick Roadmaster 1950 I need to crank several times to fuel shows up on my glass fuel filter , replaced the fuel pump and still doing the same , after several cranks it runs and then I see air in the glass fuel filter when turn it off the fuel goes back in the fuel line . Link to comment Share on other sites More sharing options...
TerryB Posted April 26, 2020 Share Posted April 26, 2020 Is this a new development or has it always done that? Link to comment Share on other sites More sharing options...
padgett Posted April 26, 2020 Share Posted April 26, 2020 Is this a new car to you ? Had a Sunbird with dual quads I always needed to prime or it would take forever to get gas. Same happens to my Judge if it sits for a while. The sucking back seems strange. Any chance you have a non-vented gas cap (emissions cars) and are supposed to have a vented cap ? Link to comment Share on other sites More sharing options...
Larry Schramm Posted April 26, 2020 Share Posted April 26, 2020 Agree, look at the vented gas cap. Link to comment Share on other sites More sharing options...
stakeside Posted April 29, 2020 Share Posted April 29, 2020 On 4/25/2020 at 4:20 PM, Sergio Santos said: Hello ! anybody can give me a info about in this issue on my Buick Roadmaster 1950 I need to crank several times to fuel shows up on my glass fuel filter , replaced the fuel pump and still doing the same , after several cranks it runs and then I see air in the glass fuel filter when turn it off the fuel goes back in the fuel line . I have found that the white tape you are using can possibly close a line. 1 Link to comment Share on other sites More sharing options...
JACK M Posted April 29, 2020 Share Posted April 29, 2020 1 hour ago, stakeside said: I have found that the white tape you are using can possibly close a line. It can if not used properly. There are many that refuse to use it at all. As for the cranking, Several of my cars need a prime after not that long of a rest. Some say the fuel syphons back, some say it modern fuels evaporate away. 1 Link to comment Share on other sites More sharing options...
Hudsy Wudsy Posted April 30, 2020 Share Posted April 30, 2020 Some Rochester carbs had a "power valve" on the bottom of the bowl that would leak down when sitting. The result was an empty carburetor bowl the next time you tried to start it. After that, a period of cranking to refill bowl and start engine. 1 Link to comment Share on other sites More sharing options...
Guest Posted April 30, 2020 Share Posted April 30, 2020 6 hours ago, Hudsy Wudsy said: Some Rochester carbs had a "power valve" on the bottom of the bowl that would leak down when sitting. The result was an empty carburetor bowl the next time you tried to start it. After that, a period of cranking to refill bowl and start engine. This is why I have an electric pump on most of my cars. Turn on ign., wait until the pump stops, and the car starts right away. 1 Link to comment Share on other sites More sharing options...
60FlatTop Posted April 30, 2020 Share Posted April 30, 2020 I have had cars that always showed air in the filter bowl. It is not a good indicator. When the car has been sitting does it squirt from the accelerator pump? That's a big cast iron heat sink the carb is sitting on. Some carbs have anti-perculation valves to keep from boiling the fuel out of the bowl. It could be vaporizing as it cools. I would be curious of how the flowing back problem was diagnosed. If you really think it is you have fitting arrangements to put a small ball valve at the filter inlet. Drive the car to full operating temperature, close the valve, and see if it starts the next morning to verify that. There are a lot of possibilities that just need a patient person to be right there. What country are you in? Bernie 1 Link to comment Share on other sites More sharing options...
46 woodie Posted April 30, 2020 Share Posted April 30, 2020 That Teflon tape can give you all sorts of trouble. All it takes is a small piece to wind up in your carb and it can get stuck in a jet, ball or orifice. 1 Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted April 30, 2020 Share Posted April 30, 2020 OP has not been back since asking the question. Ben Link to comment Share on other sites More sharing options...
JACK M Posted April 30, 2020 Share Posted April 30, 2020 In the marine industry there are some applications that require a anti syphon valve at the fuel tank. (line running lower than the tank). However this sometimes caused problems with to much restriction as the fuel pumps could not always over come the check valve. 1 Link to comment Share on other sites More sharing options...
Hans1 Posted April 30, 2020 Share Posted April 30, 2020 check valves in fuel pump 1 Link to comment Share on other sites More sharing options...
Sergio Santos Posted July 10, 2020 Author Share Posted July 10, 2020 I just installed a new fuel pump Link to comment Share on other sites More sharing options...
Sergio Santos Posted July 10, 2020 Author Share Posted July 10, 2020 Now my Cadillac 1956 doing the same thing I have to pump several times after several days not in use , the fuel filter shows no fuel on it could be faulty fuel pump ? Link to comment Share on other sites More sharing options...
W_Higgins Posted July 10, 2020 Share Posted July 10, 2020 I ran into this same issue on a '59 Cadillac. The glass sediment bowl had a cork gasket. After I changed it to a neoprene one the problem went away. It wasn't leaking. All I can figure is it was wicking out and evaporating. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now