1956 Buick Roadmaster

[Guest William Knopf]

I am new to the group. This is my first Buick. I recently acquired a 1956 Buick roadmaster. I'm not sure when it was last running. I drained the gas from the tank and put in fresh gas.  It appears it is not getting gas to the carburetor.   It will run when we manually put gas into the carburetor 

[TerryB]

The fuel pump may be bad or the fuel line is blocked with rust inside the tank.  The fact it runs with gas into the carb is a good start.  Post your questions in the Buick forum for best results.  Nice car!

 

Terry

[37_Roadmaster_C]

As Terry said, the problem is between the tank and the carb and this includes the lines, fuel pump and most likely a filter.  Start with the most obvious, the filter and go from there.  Beautiful car,  you will turn heads when she is on the road.  Welcome aboard..........

[Guest William Knopf]

Thank you TerryB and 37 Roadmaster_C. Now to figure out where the Buick Forums are, lol 

[Guest]

Back one from here (that is back to Technical) on the main page then scroll down 15. 

[Rusty_OToole]

If you drained the tank it can take a while for the gas to pump up. You may have to put gas down the carb and start it 5 or 6 times. Or dribble a little gas into the carb as it runs, the fresh gas should come up in a minute. I cut the valve stem out of an old inner tube so I could clamp it over the gas filler and pressurize the tank. It only takes 2 PSI don't pressurize it too much you could damage the tank.

[Guest William Knopf]

ok guys. We got the Buick running this afternoon. We drove it about a 100 yards in our driveway and it cuts off. Couldn't get it to start back up unless we manually put gas in the carb. Suggestions?

Is it still possibly the fuel pump. 

Edited July 13, 2017 by William Knopf (see edit history)

[37_Roadmaster_C]

It could still be any of the above mentioned areas.  The pump seems suspect, but there could be somethining in the tank intermitantly blocking the pickup or same with the carb float valve.  You will just have to start somewhere and be logical and eliminate things one at a time.  A quick and easy thing to try is to disconect the fuel line from the carb. Using a portable fuel source, gas can or such, hook a line up to the carb and allow gravity to supply gas to the carb.  Put a hose on the disconected fuel line and put it in a gas can. Start the car (if she will not start you have a carb problem).  Check that the fuel pump is pumping gas into the can....  Go from there.  The gravity feed will supply enough gas without a pump to idle the motor.  Let us know what you find.  Good Luck.

[Guest William Knopf]

Thanks. That is what dad (82) suggested we try. Thanks for the input as well. I'm loving this car. 

[Larry Schramm]

Does the car have a fuel filter?  If so might want to check that.

 

Could be in the base of the carb or somewhere else.  Not familiar with that particular car.

[lump]

Old cars are notorious for gas tanks loading up with rust and other debris. Check around to see if brand new gas tanks are available for your Buick. 

 

Also, old fuel pumps used to be made with laminated diaphragms. These diaphragms deteriorate with time, so even if you buy a brand new-old-stock pump, if it has a laminated diaphragm it may fail after only a few hours of operation. Look at the fuel pump closely, and notice where the edges of the diaphragm stick out between the bolted-together sections of the housing. Pick at the diaphragm material with your fingernail or whatever, and see if it is made up of multiple thin layers of material. If so, it is a laminated diaphragm, and should be replaced. The alternative is a modern neoprene material, which is like one layer of black rubber. Old fuel pumps that are otherwise ok can be easily "rebuilt" by installing a new neoprene diaphragm. Or, you can order a rebuilt pump from a number of reliable sources. Just specify that you want a pump with a neoprene diaphragm...not a "NOS" or "NORS" fuel pump which has been lying on a shelf somewhere for decades. 

[Ben Bruce aka First Born]

Does it have a filter in the gas line at the carb?  Especially the Morain pancake one, about 2 in diameter.  If so, consider cleaning it. If it is full of old shellac type goo, use acetone or some such to clean.

 

  Ben

[Guest William Knopf]

I have placed an order for a fuel pump from Buick nail I have placed an order for a fuel pump from Buicknailhead's.com.  I will post updates when it arrives. Hopefully this is the problem.  The gas tank looks fairly new and when I drained the existing gas, no debris appeared to be present. 

[Guest William Knopf]

 OK everyone. I got my new fuel pump in and installed. It seems to have solved many concerns.  The car starts whenever I wanted to now. I'm going to have the carburetor rebuilt next. It has a Carter carburetor. Where should I look to find a kit?  Thanks for everyone's help. 

[jvelde]

Check out bobsautomobilia.com for Buick parts or oldbuickparts.com .  Either one should have carb kits, but you will need to know which Carter carb you have.

Edited August 15, 2017 by jvelde (see edit history)

[D Yaros]

Daytona Auto Parts

[Guest William Knopf]

How do I know which Carb that I have. I know it's a Carter. I took some pictures so any help is appreciated. 

[Ben Bruce aka First Born]

That little tag on the right in pic 3 tells the story

 

  Ben

[lump]

That is a Carter WCFB carburetor, widely used in the 1950's. I have owned several of them over the years. 

[Guest William Knopf]

OK. The fuel pump has been replaced and the carburetor has been rebuilt. It still seems like it is starving for fuel, any suggestions? The filter near the back states 2 lbs PSI. 

 In order for us to relocate the car in the shed my buddy had to hold down the choke so that it wouldn't cut off when giving it gas.  

[Frank DuVal]

Quote

Bill

The filter near the back states 2 lbs PSI. 

 

Why would a filter say only 2 PSI? One from a gravity flow fuel system, i.e. lawnmower?

Are there wires going to this filter?  i.e. a fuel pump rated at 2 psi output.

 

Remove the filter and see if it 

1. really is a filter

2. is clogged

[Guest William Knopf]

OK. The fuel pump has been replaced and the carburetor has been rebuilt. It still seems like it is starving for fuel, any suggestions? The filter at the the back of the carburetor states 2 lbs PSI. It doesn't appear that the filter stays full of fuel.

 In order for us to relocate the car in the shed my buddy had to hold down the choke so that it wouldn't cut off when giving it gas.  

 

Also, since the battery wasn't charging I took off the generator and had it tested (checked out good). The voltage regulator apparently did not.  Where should I look to get one.  Rock Auto has several listed when i type in 1956 Buick Roadmaster.

 

Thanks in advance for everyones help.

[lump]

Starving for gas in an old car which sat without running for a long time is a COMMON problem. Old fuel turns to a varnish-like goo, which can clog fuel lines, etc. And just because your gas tank LOOKS like new when you shine a flashlight inside, doesn't mean that it doesn't have rusty sections hidden from view down inside. 

 

I recommend installing one or more clear fuel filters inline between the tank and your fuel pump. Then, run the car around the block a few times. Then check the fuel filters, and see if they start filling up with debris. If so, you've got a rusty gas tank, and should fix that immediately, before going any further. 

 

The fact is that a newly-rebuilt carburetor can get clogged up just as quickly as an old carburetor. Eliminate all suspicions of bad fuel/rusty gas tank/or other debris in your fuel before going any further. 

 

I would not yet get too worried about that voltage regulator. A well-charged new battery will run the car around on test drives just fine for a few weeks. The best way to diagnose a mysterious problem in an old car is to isolate one problem at a time, and then verify that you have eliminated various possibilities leading to that problem one at a time. AFTER you solve the fuel crisis, then go after any charging system issues. Good luck! 

[Akstraw]

I have a carb like this on a Cadillac, a WCFB I believe.  When I first got it, I had a problem similar to yours.  There was a cylindrical filter screen in the carburetor body right at the fuel inlet.  It was packed with rust particles.  Off the top of my head, 2 psi of fuel pressure sounds low.  It seems like you should have more like 5 or 6, though I could be wrong.  I suppose you could put a pressure gage on the outlet side of the fuel pump to measure it.  Other ideas:  Have you disconnected the fuel line at both end an blown out with compressed air?   Just because a fuel pump is new doesn't necessarily mean that it is a good one.  Should there be a cap on the big hole along side the accelerator pump cover?  I seem to recall that mine has a cap there, though I am not sure if that would relate to your problem.  With your carb rebuild kit you might have received a detailed instruction for setting the automatic choke.  It would also be in your shop manual.   By the way, the automatic choke tubes on these are notorious for rusting away at the joint to the manifold.  If the insulation is still in good shape, you won't even see the problem.  These are just some ideas to track down.  I agree with the comment that you have to eliminate one potential problem at a time.   For a year, I had a weak acceleration issue with my Caddy that I was sure was carburetor or fuel related.  It turned out to be a bad vacuum advance unit on the distributor.  Good luck.  It sure is a beautiful car!