The Ford Barn - View Single Post - No. 7 Cyl never gives evidence of a power stroke on '46 Flathead

ronchamblin · 03-31-2017, 07:46 PM

Andy ... that's a possibility. Tony ... you are correct. I've received some ambiguous info about the cranking speed pressures on the No. 7, as compared to the others. The battery is on charge overnight. I drove the Ford ('34 w/46 engine) to work today, with cylinder No. 7 not contributing at all to the engine. I also sprayed mist from a can of starting fluid near any intake manifold protrusions and gasket areas near No. 7 to see if there would be an increase in RPM. There was no change. Nor was there any change in the RPM when the wire was removed. When wires were pulled from all other cylinders, the RPM dropped noticeably. Given that the spark is high, the changed plugs make no difference, and that a manifold leak has not been found near No. 7, I suspect a valve problem. Upon checking the compression again in the morning, if I discover that No. 7 is low, then I will remove the intake manifold and inspect the valves.

03-31-2017, 07:46 PM	#12
ronchamblin Junior Member Join Date: Aug 2013 Location: Jacksonville, Florida Posts: 13	Re: No. 7 Cyl never gives evidence of a power stroke on '46 Flathead Andy ... that's a possibility. Tony ... you are correct. I've received some ambiguous info about the cranking speed pressures on the No. 7, as compared to the others. The battery is on charge overnight. I drove the Ford ('34 w/46 engine) to work today, with cylinder No. 7 not contributing at all to the engine. I also sprayed mist from a can of starting fluid near any intake manifold protrusions and gasket areas near No. 7 to see if there would be an increase in RPM. There was no change. Nor was there any change in the RPM when the wire was removed. When wires were pulled from all other cylinders, the RPM dropped noticeably. Given that the spark is high, the changed plugs make no difference, and that a manifold leak has not been found near No. 7, I suspect a valve problem. Upon checking the compression again in the morning, if I discover that No. 7 is low, then I will remove the intake manifold and inspect the valves.