I have a WCD Carter 2bbl carburetor on my 1950 Pontiac that is giving me problems. I am trying to get the car running for the first time in many years so I had the carb rebuilt, ran all new gas lines and installed a 6 volt electric fuel pump until I convert to a 12 volt system. When I power the pump on it pumps gas straight through the carb and out two small holes near the top on the back of the carb. I did take the fuel filter right behind the carb out because I have an inline filter between the pump and the tank as required by the pump manufacturer. Is there something wrong in the carb or do I need to reduce the pressure. I think it is around 5 psi now. Thanks for any and all help.
First thing you need to do is be sure your electric pump is putting out the proper pressure. Make a trip to Harbor Freight and get yourself a cheap pressure gauge for this. Here is a fantastic article on those carburetors. https://www.hometownbuick.com/1953-buick-carter-2-barrel-carburetor/
To me it sounds like a float, needle/seat problem. Float should shut gas off at the correct level in bowl if it's working properly. Sent from my SM-S320VL using Tapatalk
I got a reply on another forum saying that the electric pump is too much for my old car. My carb is rated a 5.25 PSI at full throttle and much less then that at idle. The electric pump is putting out around 5 or 6 PSI. I have a rebuilt mechanical pump on another car that I will install on this one to see if that solves my problem. The reason I installed the electric pump to begin with is because the car is pushed up against the wall in my shop and the passenger side where the mechanical pump sits is very hard to get to. Looks like tomorrow is going to be a blast!
They make fuel pressure regulators which are easy to install. With that you can set psi at anything you want. I personally don't think 5 psi is excessive though. Sent from my SM-S320VL using Tapatalk
Holley makes an adjustable inline regulator that may help wit the pressure issue. I used it wit good results on a OT car with SU carbs. This one is 1-6psi They also have 4.5-9psi version Chappy https://www.holley.com/products/fue...s/regulators/carbureted_regulators/parts/9710
A simple test to find out if there is something holding the needle valve open like dirt or stuck needle or stuck float, is if you have a small gravity gas tank off of a small engine?...just hang that small tank higher than the carb with motor not running and see if the gas still overflows. .
Stupid question.... are you running the 6 volt pump on 12 volts? or did you replace it with a 12 volt pump?
Most likely trash in the needle & seat. When you make 'all new gas lines' there'll be bits and pieces of trash inside the hoses and thats whats gone into the needle & seat. The old farmer would peck the top of the fitting where the needle & seat are located with a cresent wrench, the HAMB approved method would be to take the top off the carb and clean the junk out. We always wash out new hoses before installing them. Another common mistake is using teflon tape to seal the inlet fitting threads, pieces if the take will go to the needle & seat too. Holley voids the warranty if you use teflon tape.
@fyrffytr1 The car I used it on was a 12v pos ground (Lucas) with a mechanical pump. Flow is not pressure and pressure is not flow.... Chappy
I stopped by work today and picked up a 1-6 PSI regulator and installed it when I got home. I powered up the electric pump with the regulator set on 1 and no gas came out of the carb so I gradually increased the pressure until it was up to 5 PSI and still no leaks. So, I turned the ignition switch off and hit the starter button to crank the motor over for about 10 seconds at a time for a minute or two. And, yes the starter on my car will work with the ignition turned off. Then,I sprayed a shot of starter fluid in the carb, turned the key on and hit the starter. After a few seconds the motor caught and began to run. There was a little valve noise at first but it quieted down and the motor idled until I shut it off. The oil pressure gauge was showing pressure so I think I am going to be OK. I still have to pull the thermostat and replace it just to be on the safe side. And, I need to flush the engine and change the oil. I will probably do this a couple times. This is the first time the motor has ran since the early 80s! I am now ready to move onto the brakes. Hopefully it will move and stop after I get them rebuilt but the clutch is still an unknown. After I get everything else working I will have the mechanical pump rebuilt and switch back to it. Thanks for the help and be ready for my next problem.
Glad the regulator worked for you. When you start on your mechanical pump, rebuilding kits with O.E. calibrated parts are available from "Then and Now Automotive" (possibly others). Some of the rebuilding kits are a "one size fits all, works well on none". It is quite possible, if the wrong return spring is installed in the mechanical pump, for the mechanical pump to output more pressure than your electric. That WCD is a wonderful two-barrel carb, it just doesn't want too much pressure. The dual pontoon float gives excellent service on less than level terrain, but it just wasn't designed for pressure. Jon.
You may want to reconsider "flushing" the engine. Several quick oil changes will clean it without breaking loose the deposits under the rings, leading to an oil burner. When it fired, you didn't hear valve noise that went away - L-heads with flat tappets don't do that. Could have been chunks of carbon on a piston. Time for a compression test. If it's close to even, then you'll know what you have to work with.
Thanks. I ordered a kit from them for the other motor's pump and will do the same when I get this one off and see if there are any numbers on it to go by. How would these carbs work on an Edmunds dual carb intake? I know I would have to get adapter plates to go from the 3 bolt intake flange to the 4 bolt carb base plate.
Thanks for the reply. I am not sure what the noise came from but after running for less than a minute the motor quieted down and now runs smoothly every time I crank it. But, I will do a compression test before really getting into this project.
The noise you heard was problaly the ether burning in the cylinders. It takes a while for starting fluid to get out of the intake manifold. Need to use it sparingly, a lot of engines have been destroyed using it. Bones
Kudos on common sense and a cool head to start it. Brakes should be a breeze...IF you can move that pesky wall out of your way...
I have to move a few cars around but I will get to the brakes next week if my body lets me. I plan on jacking the rear end up, cranking the car and seeing if the clutch works before moving onto the brakes.
I had a few hours free this afternoon so I jacked the rear of the car up, put jack stands under the frame and cranked the motor up. The first time I let out on the clutch the motor stalled but the second time the driver's side rear wheel started spinning. I went through all three forward gears with no problem so I used the parking brake to stop the tire and then I put the tranny in reverse. Again, no problem so I know the clutch is working but I won't know how well until I get it on the road. It doesn't engage until the pedal is over half way to the top of its travel so I am of the opinion that a new clutch may be needed. I might be able to adjust the linkage and get the clutch to engage a little sooner but that is another day. I hope to start on the brakes this week.
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