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| | | | Joined: May 2007 Posts: 222 Shop Shark | | Shop Shark Joined: May 2007 Posts: 222 | PTL it’s running but rough. 1949 216 engine original, rebuilt with new everything. Engine is timed, dwell is set at 30 degrees, and point gap at .022. It idles down well, but the engine is running rough. We pulled the front two plugs, suspecting an ignition issue, but did not discern much change in the engine performance with the wires off. The rear four plugs made a big difference when they were taken off. We adjusted the valves a few months back, but one is still a bit noisy. Vacuum appears to be ok, but I haven’t ’s put a gage on it. So in light of this what can “I do to improve performance and what is your thoughts on the front two plugs? We cleaned all the plugs because they were carboned up. Thanks for any and all your help and in sight.
God bless,
Dave
Joh 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
| | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy Panelit, did you clean the intake manifold on the inside from one end to the other? There could be something in there stopping the air/fuel mixture getting to the front two cylinders. Other than something like that, I would suspect a vacuum leak at the front of the manifold, put a vacuum gauge on it and see what you get. You can also check for vacuum leaks by spraying carb cleaner at the junction of the head and intake manifold, or you can use a propane torch [not lit] in the same way, be careful, please keep us informed. | | | | | Joined: Jan 2004 Posts: 188 Shop Shark | | Shop Shark Joined: Jan 2004 Posts: 188 | Do a compression test all cylinders and compare. Are you getting spark to those two front plugs, i.e. wires ok? | | | | | Joined: May 2007 Posts: 222 Shop Shark | | Shop Shark Joined: May 2007 Posts: 222 | Will check the manifold, it was clean when installed last night. Spark is good, we pulled the wires while running amd there is good spark; almost got knocked on our back side a couple of times due to getting a shock. Wires, plugs, and points are all new.
Joh 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
| | | | | Joined: Mar 2005 Posts: 1,636 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 1,636 | Could the plug wires simply be swapped on those two cylinders? Might try swapping the two wires on the two that rfen't hitting and see if it helps. | | | | | Joined: Sep 2010 Posts: 695 Shop Shark | | Shop Shark Joined: Sep 2010 Posts: 695 | Spark is good, we pulled the wires while running amd there is good spark; almost got knocked on our back side a couple of times due to getting a shock. Sorry, had a chuckle out of this one... been there, done that. There are quite a few different things that can create symptoms. Sounds like you're getting some good tips to check so far. My first thoughts were vacuum leak, fuel supply, crossed wires, plug gap (since fire is good to the plug...) check fire at the plug ignitor. Also comes a question... Did you redo the heads? valve seats ok etc.? A compression test might answer this. Hope this is a minor issue, quickly resolved. Jerry | | |
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