LarryP Posted July 24, 2014 Share Posted July 24, 2014 I've owned my Model A for a month now, and today for the first time decided to drive it to work (about 10 miles on easy driving roads). For the first 5 or so miles I was tooling along at a comfortable 35 to 40 mph. Unfortunately, as I got closer to work, I started to loose power, until I couldn't go over 20. If I tried giving it more gas, the engine would back fire through the carburetor. After it stalled and I pulled to the side of the road, I was able to restart it, but it would only stay running if I kept the timing retarded (lever all the way up). If I moved the lever even 1/4 inch down, it would shotgun backfire out of the exhaust and stall. I limped the final mile to work, and it is sitting in the parking lot. Please help! What went wrong? Did I just burn out the condensor? It is still the old style (mounted in bottom of distributor housing). Or, did the screw holding the cam in place in the distributor come loose? I did not have time to look at it, as by this time I was running late for work. I will work on it in the parking lot after work. Any thoughts would be greatly appreciated!Larry Link to comment Share on other sites More sharing options...
MCHinson Posted July 25, 2014 Share Posted July 25, 2014 From the Model A Ford Technical Questions section...https://www.mafca.com/tqa_e_other.html"Back firing is usually caused by the condenser failing or... the points may not have sufficient gap. Make sure they are set at .018 to .020". Make sure they are not burnt. Backfiring can be caused by intermittent firing of the ignition system or very lean fuel mixture. If the car has been setting for a while, the carburetor float valve may be sticking. Clean the float valve good and set the float level. Backfiring due to intermittent ignition can be caused by a frayed wire on the bottom side of the distributor plate . . or .. by intermittent connection of the ignition switch. 1.) Check point setting first. 2.) replace condenser next. Make sure the condenser you buy is the right length, some are too short, and that it is a good quality. 3.) Check that the carburetor float valve is operating correctly. 4.) Sometimes the pop out type ignition switches get intermittent. As a last resort, replace the ignition switch/cable." I would check for a frayed wire on the bottom side of the distributor plate first. The fact that moving the spark control lever causes it to die makes me think that may be your problem. Link to comment Share on other sites More sharing options...
LarryP Posted July 25, 2014 Author Share Posted July 25, 2014 From the Model A Ford Technical Questions section...https://www.mafca.com/tqa_e_other.html"Back firing is usually caused by the condenser failing or... the points may not have sufficient gap. Make sure they are set at .018 to .020". Make sure they are not burnt. Backfiring can be caused by intermittent firing of the ignition system or very lean fuel mixture. If the car has been setting for a while, the carburetor float valve may be sticking. Clean the float valve good and set the float level. Backfiring due to intermittent ignition can be caused by a frayed wire on the bottom side of the distributor plate . . or .. by intermittent connection of the ignition switch. 1.) Check point setting first. 2.) replace condenser next. Make sure the condenser you buy is the right length, some are too short, and that it is a good quality. 3.) Check that the carburetor float valve is operating correctly. 4.) Sometimes the pop out type ignition switches get intermittent. As a last resort, replace the ignition switch/cable." I would check for a frayed wire on the bottom side of the distributor plate first. The fact that moving the spark control lever causes it to die makes me think that may be your problem.Thank you so much Matthew!I will check for a frayed wire later today. As you say, this makes lots of sense, giving it stalls when I move the spark control lever. I tried most of your other suggestions first thing yesterday. I checked the points (twice) and they were set at 0.20. I checked the timing (also twice). Then replaced the condenser with a spare I keep on hand. I disassembled and cleaned the carburetor (no dirt was found inside and all appeared to be normal). So I hope I'm down to one of two things - (1) the wire under the distributor plate, or (2) the pop-out ignition. Will turn to it later today and let you know results.Thanks againLarry Link to comment Share on other sites More sharing options...
dl456 Posted July 25, 2014 Share Posted July 25, 2014 Larry, May sound stupid but be sure your gas cap is venting or that you haven'tswitched the radiator and fuel cap. Don't ask how I know.Dennis Link to comment Share on other sites More sharing options...
LarryP Posted July 26, 2014 Author Share Posted July 26, 2014 Larry, May sound stupid but be sure your gas cap is venting or that you haven'tswitched the radiator and fuel cap. Don't ask how I know.DennisLove your post Dennis! I've not switched them, but hey, they may have been mixed up when I got the car. Not sure if it is venting or not. I will take a look. By the way, checked the wire under the plate in the distributor. Surprisingly good shape. Found nothing wrong with it. Did not replace it, although I will, just to be sure. As I was sitting in a parking lot, though, I thought I would wait for that job until I got it home. Just had it towed home last night and will dive in deeper tomorrow. Link to comment Share on other sites More sharing options...
mercer09 Posted July 26, 2014 Share Posted July 26, 2014 check your gas shut off valve and make sure there isnt crap in the bottom of your tank, starving the fuel flow........... Link to comment Share on other sites More sharing options...
JFranklin Posted July 27, 2014 Share Posted July 27, 2014 Don't replace parts just for the fun of it, you may dig a deeper hole! Link to comment Share on other sites More sharing options...
LarryP Posted August 5, 2014 Author Share Posted August 5, 2014 Well, its been a while since I last replied, and I thought I would let you all know what I found.It ends up that Matthew was correct. The wire under the distributor plate was frayed. When I checked in a parking lot as evening was quickly approaching, I apparently didn't look close enough. When I got it home and in the garage, I found that sure enough, the wire was frayed. I replaced the wire, and the problem went away (that is, the problem of the engine cutting out when I moved the spark control lever). The car still was not running great though, and I had thoroughly cleaned everything in the fuel system. There was a slight wabble of the distributor shaft though (worn bushings), so I purchased a rebuilt distributor. Man, this old A runs like a new car now! I am amazed how well it runs. Here's a quick plug for Renner's Corner Early Ford Parts, where I purchased the distributor. They do great work! The distributor both looks great and works great. And they were fast with delivery. This father & son business does the work themselves, machining new shaft and bushings (including drilling down the center for oil), sandblasting and painting the cast iron housing, and installing new points & condensor. Thanks everyone! Link to comment Share on other sites More sharing options...
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