Aaron Posted August 18, 2008 Report Share Posted August 18, 2008 I have been trying to get my B1B running smoother, but having some problems. It starts well and idles very good, the problem arises when stepping on the gas, it wants to dog down in every gear. When I take it on the highway and get it in 3rd she really dogs when trying to get her up to speed and just runs terrible when getting up to 35-40mph. I have put a new carb kit in, new points with adjustments, new spark plugs, new coil, new condensor, new rotor and cap. Tried adjusting the carb, but didn't make any type of difference. Checked timing and is good. I'm lost at this point on what to try, any ideas?? Quote Link to comment Share on other sites More sharing options...
JoelOkie Posted August 18, 2008 Report Share Posted August 18, 2008 Weak fuel pump? Vacuum advance? Sounds like your ignition has all been covered, so maybe fuel related then. I once had a similar issue with a 46 plymouth coupe I had just bought that had sat for a number of years in which the oilite (sp?) filter in the fuel tank was almost all shut off with accumulated varnish, and there was not a sufficiant volume of fuel leaving the tank for acceleration. The car would start and idle, but that's as far as it went. It seemed to be getting fuel ok at the carb, until I checked the flow volume by unhooking the line past the fuel pump and catching the fuel while cranking. Barely a little actually moving through the line. I "installed" the old one gallon gas tank under the hood test, and the engine worked perfectly. I ended up cutting the top out of the tank to get to it. Joel Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted August 18, 2008 Report Share Posted August 18, 2008 Remove the leather accelerator pump from your carburetor and soak it in oil overnight. Reinstall and you should be good to go. Quote Link to comment Share on other sites More sharing options...
greg g Posted August 18, 2008 Report Share Posted August 18, 2008 There is also an internal power circuit in the carb which completes the enrinchment process started by the accelerator pump. The acc pump gives you a short shor of extra gas, the power circuit is meant to give a more sustained enrichment until the throttle is releases. It is a jet with a tapered needle which is kepted closed by a passage that opens to manifold vacuum at the base of the carb. High vacuum at idle at at cruise, keeps the needle down in the jet. As manifold vacuum decreases with throttle opening, a spring lifts the needle out of the jet giving a metered enrichment based on the vacuum available. If this passage is blocked or the piston is stuck, the will not operate properly. Some times it is as simple as the gasket between the carb and intake being placed on incorrectly. You cna check it phisicaly by removing the top of the carb, and locating the assembly on the left side of the air float bowl (when looking at the carb from the front) check for a flat bar with a piston on one end and a needle on the other and a spring under the connecting bar. This should move up and down freely against the spring. The carb has a hole in the small hole in the bottom of the mounting flange. This needs to be alligned with a slot in the gasket in order to vet the vacuum signal from the intake. If this and your acc pump are working properly, it should clear up andy bogging problems assuming your fule flow is correct and your vacuum and mechaical advance are working correctly. To test your fuel flow, disconnect the line at the carb, direct it into a suitable container. Disconnect the coil wire and crank the engine. this works best as a two person deal, the observer should count the pulsed of fuel as the engine turns over, 12 strokes should give you 8 ounces or more of gas in the container. You can also disconnect the fule line on the tank side of the pump and blow some compressed air through back toward the tank. this will usually clear any accumulated stuff of the intank filter. Don;t use more the 15 to 20 lbs of line pressure. Quote Link to comment Share on other sites More sharing options...
grey beard Posted August 19, 2008 Report Share Posted August 19, 2008 If the accelerator pump does not fix the problem, check your vacuum advance unit for a leak. It should advance the timing on acceleration. Check it out with a degree timing light. JMHO Good Luck Quote Link to comment Share on other sites More sharing options...
Aaron Posted September 1, 2008 Author Report Share Posted September 1, 2008 I finally found some time today to work on the old gal. I have followed some of the advice you guys have given. took the top off the carb and checked the spring action and gasket position and all seems good. Cranked the engine and collected the fuel, seemed to come out, but hard to count 12 cranks and if I did it right, I'm pretty sure I didn't have 8 ounces of fuel, maybe 4 ounces. So that could be a problem. The fuel pump is new by the way. Right now I am looking at the vacuum looking thing which is located on top of the distributer. How do you get this thing off? I have the two screws off and the line that goes to the top, but it is connected to something in the distributer. How do I get this off and is there a way to check it to see if there is a problem with it? So in other words, I am no further along, still idles nice but doggy when giving it fuel. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted September 1, 2008 Report Share Posted September 1, 2008 Did you remove your accelerator pump leather and soak it in oil? Quote Link to comment Share on other sites More sharing options...
Aaron Posted September 1, 2008 Author Report Share Posted September 1, 2008 I saw your post before and couldn't think of anything leather in the carburator, but now it just came to me, I know exactly what you are refering too. I will pull that and soak it in oil and see what happens. Thanks Quote Link to comment Share on other sites More sharing options...
Aaron Posted September 4, 2008 Author Report Share Posted September 4, 2008 Don, I did what you said and soaked the leather accelerator pump over night in oil. Put it back together last night and took it out for a spin and have the same problem. I get it up to about 30 mph and the truck starts to spit and sputter and just sounds terrible. Below 30 mph it runs great. I'm starting to wonder if there is a problem with the fuel pump now... Quote Link to comment Share on other sites More sharing options...
Guest Kuster13 Posted September 4, 2008 Report Share Posted September 4, 2008 It has been awhile since I've had my motor running but might I suggest revisiting the distributor. Test the vaccum advance with a hand vaccum pump and check that the governor weights in the distributor are movng freely. An exploded view of the distributor is available in the Pilots Knowledge section of the DPETCA site. Hope this helps. Tom Quote Link to comment Share on other sites More sharing options...
Aaron Posted September 5, 2008 Author Report Share Posted September 5, 2008 not sure what a hand vacuum pump is or how I would go about testing the vacuum advance. Anyone have a picture to give me an idea how to go about this? Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted September 5, 2008 Report Share Posted September 5, 2008 not sure what a hand vacuum pump is or how I] would go about testing the vacuum advance. Anyone have a picture to give me an idea how to go about this? Pictured below is a hand vacuum pump. To use it you connect the rubber hose to the vacuum advance pot on the side of the distributor. Then pump it to pull vacuum while observing the points plate inside the distributor. Note the inches of mercury when you first see movement and the inches of mercury when the movement stops. Compare these numbers to the book and make adjustments by adding or removing shims under the spring located inside the vacuum pot below the rubber hose connection. The book readings will be something like 2 degrees @ 3" of mercury and full in 9 degrees @ 15" of mercury. Quote Link to comment Share on other sites More sharing options...
greg g Posted September 6, 2008 Report Share Posted September 6, 2008 Also check the wire inside the dist that connects the points terminal on the distributor to the points themselves. This wire flexes as the breaker plate moves. If the insulation frays it can ground against the distributor at certain rpms and short out the points. The cable strands within the short wire can also break over time creating either breaks iin flow all together or cause resistance by having the current flow through fewer strands of wire. I found mine frayed and wrapped it in silk hread coated with rubber cement. Reinstalled after the glue cured has been fine for 4 years. Quote Link to comment Share on other sites More sharing options...
TodFitch Posted September 6, 2008 Report Share Posted September 6, 2008 ...Cranked the engine and collected the fuel, seemed to come out, but hard to count 12 cranks and if I did it right, I'm pretty sure I didn't have 8 ounces of fuel, maybe 4 ounces. So that could be a problem. The fuel pump is new by the way.... Sounds like you have a problem here. I'd fix that before ripping into the carburetor or distributor. Since you have a new fuel pump, I'd check to see if you line from the tank to the pump is clogged or if the in-tank filter is clogged. Quote Link to comment Share on other sites More sharing options...
greg g Posted September 6, 2008 Report Share Posted September 6, 2008 disconnect the line on the tank side of the fuel pump and put some low pressure air back through the line into the tank. Remove the gascap and listen for bubbles from the tank. The air will blow any debris off the in tank filter. then do the test again. If you have a helper crank while you count its easier. Quote Link to comment Share on other sites More sharing options...
Bill pilot99 Posted September 6, 2008 Report Share Posted September 6, 2008 My brother's 49 plymouth had the same problem, we found pin holes in the gas line. It was sucking air into the line. This was in 1956. Good luck! Quote Link to comment Share on other sites More sharing options...
Aaron Posted September 6, 2008 Author Report Share Posted September 6, 2008 Tank filter? I'm pretty sure I don't have a tank filter since this past spring I had the tank fixed by a welder and I cleaned the entire thing out. Never saw a filter... I hooked a different small fuel tank up to the the fuel pump and had the same problem. So I don't think the problem is coming from the original gas tank. Quote Link to comment Share on other sites More sharing options...
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