Lately I've been chasing a wobbly vacuum needle and intermittent misfire on my Rochester equipped 2.25. I had the Carb rebuilt professionally and have fiddled to a steady vacuum reading and eliminated the misfire.
I ran the Rover around the block last night - it ran perfectly. Lots of power, steady vacuum needle, great idle. I decided to run it up to approx. 3200 rpm and listen for any problems. I ran it up to 50 mph and came to a stop at a red light. The vacuum gauge dropped to 12 or 15 and the needle was very erratic. The truck would not idle but shifting up through the gears the needle was steady and there was lots of power. Engine breaking up to a stop light produced lots of backfiring at the exhaust and coming to a stop - again the vehicle wouldn't idle.
I pulled the truck into a side street and shut of the ignition. The engine ran on for a few revolutions before coming to a stop. I let it sit for a minute or two - started it up - and everything was fine. Steady idle, lots of power. The minute I run it up to higher RPM's the symptoms return. Again - shut it off, restart - the truck is back to behaving itself.
I've switched the coil, checked the timing, ignition parts are all pretty new. There doesn't seem to be any fuel issues. Lots of fuel in the bowl - no sign of air bubble revving the engine in the driveway. Any ideas?
Thanks again,
Henry
I ran the Rover around the block last night - it ran perfectly. Lots of power, steady vacuum needle, great idle. I decided to run it up to approx. 3200 rpm and listen for any problems. I ran it up to 50 mph and came to a stop at a red light. The vacuum gauge dropped to 12 or 15 and the needle was very erratic. The truck would not idle but shifting up through the gears the needle was steady and there was lots of power. Engine breaking up to a stop light produced lots of backfiring at the exhaust and coming to a stop - again the vehicle wouldn't idle.
I pulled the truck into a side street and shut of the ignition. The engine ran on for a few revolutions before coming to a stop. I let it sit for a minute or two - started it up - and everything was fine. Steady idle, lots of power. The minute I run it up to higher RPM's the symptoms return. Again - shut it off, restart - the truck is back to behaving itself.
I've switched the coil, checked the timing, ignition parts are all pretty new. There doesn't seem to be any fuel issues. Lots of fuel in the bowl - no sign of air bubble revving the engine in the driveway. Any ideas?
Thanks again,
Henry
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