I have a 1957 Ford 292 engine and it is misfiring on cylinders 4 and 8. What could be the problem?
I had a 312 cid in my 1956 Ford. There are several possibilities and in the firing order, cylinders 4 and 8 are next to each other in Counter Clockwise firing order.
There is a ridge on the cap which matches a slot on the distributor and allows the 2 parts to interlock and mesh. Any other rotation of the cap will tip the cap off center and increase the firing gap on the high side while possibly causing the opposing terminals to scrape.
Wear in breaker plate bushing or distributor shaft bushing. Easily determined if you can find a real old-time speed shop with a Distributor curve machine. What happens is torque shifts the spinning distributor shaft to the side of the bushing with excess play. Basically same thing happens with a worn breaker plate; movement causes misalignment of breaker plate and points lose gap when breaker cam tries to lift points.
If removed you can fiddle with distributor shaft and put points on "High-cam" for each cylinder and measure point gap. Logically, if perfect, each "High Cam" has the same gap. But wear will show up if you put pressure either on the breaker plate or the distributor shaft.
There is a spring pin holding the distributor gear onto the shaft. You may find a seal on the shaft at some point. The parts were lubed by the oil "sling" onto the distributor housing, You may be able to "180" the distributor drive gear so mark it relative to the distributor shaft.
Other than the above, I do not know if an 8mm wire would fit into the Distributor cap; the older wires were 7mm 0r thinner and sometimes spark would jump if the wires crossed.
Finally, and much more expensive would be worn rear Camshaft bushings. 4 and 8, I believe were opposed and wobble could account for non electrical misfiring.
I hope my info has helped you. Would be interested in what you found.
Aug 02, 2013 |
Ford Cars & Trucks