well, I got my B motor in the '31 with the 5 speed, runs well on the lift, went for a ride around the block, 1'st gear was great, it got sideways. @nd was another story, it backfired through carb and exhaust although it would settle down and cruise. I have a 6v pump with Offy pressure regulator, but the pump ****ped out ( another question there) so I filled the tank and went with gravity, is the pump likely to fix this problem? Also would the regulator make the pump **** out, it siezed, was brand new from Snyders. Another note, I got a rebuild kit from Speedy Bill, came with a bad power valve ! Thanks ! Matt Cream Ridge, NJ
I'd look at ignition first. Possibly cracked/ defective insulation somewhere in the spark that will make the engine crossfire, in other words causes the engine to fire out of time. Also can be caused by sticky valves. The carb is way down on my list for this one.
I would think that the siezed pump would hinder the fuel flow a fair bit. Byp*** it and go with the gavity and see what happens. A backfire can supposedly screw the power valve, but I've never had it happen myself. What are your plugs telling you? Are they sooty, indicating a rich mixture? Flatman
Well, The motor is newly rebuilt, the distributer came out of the A motor that was in there and that ran fine, it has recent points & condensor. I have another set and wil try swapping them when I get back to it. hadn't pulled plugs yet but did remove the fuel pump and am running on gravity. Did fill tank for the most pressure. I hope to get over there this afternoon. thanks ! Matt
Back firing through the carb is 99% of the time because it is going lean. Since you had a solid 1st gear pull I'd look at fuel delivery, filter, pump. tank exit/pickup ETC.
Try the monthly banger meet here on the hamb. If the motor is stock that carb might be too much. It should run fine with gravity, but you will have problems with a low tank and hills. I had an a that had the same symtems, my tank was dirty. Double check timing.
I had a 94 that I completely rebuilt top to bottom. It would backfire, and kick, and occasionally run real well.... I thought it was ignition issues as well. I picked up 3 NOS 94's and threw one on just for the hell of it. Problem solved. Smooth idle, no back firing, nothing. I pulled the 94 I had in there completely aapart, I have yet to figure out what the issue is. I don't know if its warped somwehere or what. Oh yeah, I had this setup on an "A" engine.
The motor is a B with a winfield 1A cam, 3/8" stroker crank, chevy 293 pistons and an original cragar OHV head. Have cast iron headder ( Snyders) and a vintage Burns down draft intake. Flywheel cut down to 34 # with a V8 clutch and T-5 trans. I have abunch of 94's the one that I was using has been gone through. I'm thinking that it needs the fuel pump. Or maybe it needs the vintage Zypher intake with 2 of them....
I don't understand this thread. ***le of thread is "Holley 94 troubles or?". A Holley 94 is a downdraft carburetor (sits on top of manifold). Both the Ford A and Ford B came with an updraft carburetor (hangs underneath the manifold). If the fuel pump failed, how is the fuel going to run uphill into the carburetor? Even if you have lowered the carburetor such that the fuel tank is above it, the Holley 94 is designed to be filled by a fuel pump, and the fuel valve orifice would be too small to be filled via gravity. Example: the fuel orifice for a 1928 Chevrolet 4 banger (gravity) is 0.140 inch. The fuel orifice for a 1971 Pontiac 455 HO (pump) is only 0.135. What am I missing??? Jon.
A friend of mine had an electric pump and mechanic connected series and the electric had some problems, causing similar behaviour as yours. So id ditch the electric pump. To start with.
Ok Jon, the motor is in a Model A, the fuel tank is ABOVE the carby even a downdraft, hence my filling the tank to the top for maximim pressure. The burns intake is an aftermarket unit which takes a down draft carby & putsit on a A or a B. I read where these carbs like a maximum of 3 psi so I had a pressure regulator on the pump. The siezed pump is gone now, just a fuel line from tank to carby. I'm thinking the pump is what it needs. Although is over 3 PSI it will cause troubles. I'll beback tothe shop around 3:30 when my chores are done. Shucking lotws of oysters today for Oyster Chowder dinner. Gonna be abig pot, feel free to come by ! Cheers! Matt
Yeah, at best you have 12" of head pressure (.5 PSI) and that is not enough. You need a pump. I'm sure you are simply bleeding the bowl dry and going lean, pop........ People run those carbs at 4 +/- psi regularly. Not saying you won't have an issue at 5 but better to know you have fuel pressure then none.
Well, that is sorted. The 94 carby had teeny tiny main jets and was way lean. I put 61 jets in and now it goes like stink! What a blast! I have gone with a 12v conversion as the starter just wouldn't turn it over on 6, too much compression I guess. I am having some smoking issues and think that is just the way it is. The valves are in troughs which ( of course ) fill with oil. On decel and at idle it smokes pretty good. I am guessing there are no valve seals on a original stock cragar ohv head? I've not had it apart and didn't build it so don't know. Anyone Know? But it sure is fun to drive! the T-5 works fantastic, the engine makes a kinda funky hi po noise that people don't recognize. I have adapted the stock A exhaust system to the header, but plan to try a California Turbo muffler and 2" pipe. As funds allow I'll get some tires for the 16" spoke wheels that came back from the powder coating shop an awesome red... think thats next. This is the coolest thing i've done in years!
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