Bogging down in third

ok yawl, got the wheels on the truck and am going to adjust the brakes tomorrow as it's raining now. got the truck running and I'll be dammed if it aint running like a sewing machine. no sputter, no backfiring. now this was just sitting in the carport, but my instincts tell me it will run well when I do the test drive. I set the gav between 1/8 and 1/4 turn open and it just purred. I'm thinking that bogging down might have been something clogging the compensator, but we shall see. Fingers and toes crossed. Maybe Sunny is just happy to be running again, who knows. :):):D
 
ok yawl, here is the scoop. I got the brakes working and I took it around the block, when the gav was open about 1/8 turn open, and shifted into third at 18, I could firewall the throttle and it pulls firmly, much better than before. after driving a while with temp gauge registering 160-170, it seemed to lose a bit of pep, but that might just be the gav needing a bit of fiddling. now when letting off the gas to shift it still pops a bit in the muffler. so Sunny is still being a Wiseguy. so, tell me, what's up with it?
 
Did you blow out the jets and passages and if you did do you think that this is something that helped?
As far as the popping on deceleration I would suspect a leaky gasket on the intake manifold. Spray some starting fluid all around the gasket mating surfaces of the intake/exhaust manifolds when the engine is running at idle to see if the engine speed changes when doing so. If it does then you have a leaky gasket.
 
i checked em and blew the jets out a bit, and it did seem to help. as for gasket leak, not surprised. my manifolds probable not perfectly flat. so today I'll take em off and file em a bit if need be. let me tell you, going through the brakes entirely is the best decision on that a model one can make. it stops on a dime and gives seven cents change.
 
Sunny, if you remove the manifolds, lay them on the bench and check for flatness with a metal, straight edged square. Check that the holes are in line. #4 exhaust is often drooped. You'll need a machine shop to fix the flatness unless its a burr or something. My old manifold was drooped front and rear!
 
Howdy Rob. Well, I got the model a out on the road and gave it the beans a bit and it cruises nicely at 45 now much better than before. I took the manifolds off and measured a 0.004" gap between the intake and exhaust manifolds, so I filed them down by hand and got it to zero. I am a metalworker and had the day off, so I said send it. only bugaboos left in the pickup is lack of a Mitchell and some small things to piddle on. but other than that, it's running well.
 
OK. Old post but new problem for me. My car is doing the exact same thing...runs great in first and second...shift into third at any speed and it feels like I just tried to start out in third...loses power, struggles with an incline. So am I to understand the original poster here solved his problem by good luck...assuming a clog in the carburetor...?
 
jg61hawk said:
OK. Old post but new problem for me. My car is doing the exact same thing...runs great in first and second...shift into third at any speed and it feels like I just tried to start out in third...loses power, struggles with an incline. So am I to understand the original poster here solved his problem by good luck...assuming a clog in the carburetor...?
Click to expand...

First of all, let's start with some of the basics and work up from there. when you are driving, how much advance are you running, and are you running with the GAV or gas adjuster valve open? on a stock A with the carburetor jets at factory specs it should run a bit on the lean side. if too rich they bog down easily. to see how rich it is pull a spark plug out, ideally all four. if they are dark to medium tan, that's pretty good, if black and sooty, we need to work on that. first verify that the points, plug gaps, and timing are all to spec. 0.018"-0.022" for the points, 0.020" ideal, 0.035" plug gap, and spark advance 5 degrees after top dead center, or on top dead center and one full click down on quadrant. after verifying that the ignition is satisfactory, adjust the idle mixture by screwing in clockwise until it stumbles, and note the position, and start counting half revolutions counterclockwise until it stumbles again, and not position, then go halfway in between and just a touch counter clockwise. it should come out to be between 1.5 and 3 turns back off of full closed. if the carb is ok and you are running the correct amount of advance for the driving conditions, next on the list is check the exhaust for something clogging it. if clear, if you have one check compression. it should be about 55-65 psi. if all 4 cylinders are good on compression, remove the valve cover and check to see if the cam timing is off, if so it can bog down.
 
I found the problem...I caused it too.... I'm the only one that works on the car so I blame myself....I guess I routed the condenser wire incorrectly at some point and it looks like it either was pinched by the distributor body or it got whacked by the rotor. Thanks for the help. I am starting a new post about what happened next as I tried to fix this....I will call it a Maddening Model A Day.
 

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