11-02-2015, 10:16 PM | #1 |
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"Missing"
Hi again guys:
My 1929 RPU has started to "miss" a bit, especially when not fully warmed up. I have just recently filed and re-gapped the ignition points, re-timed the engine and cleaned and re-gapped the plugs, so all should be OK. What is the most common cause of "missing"? |
11-02-2015, 10:26 PM | #2 |
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Re: "Missing"
Weak or lost spark and poor or lack of fuel are main causes of a miss. Hold the coil wire a bit out of the cap and check for a hot consistent spark.
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11-03-2015, 05:49 AM | #3 |
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Re: "Missing"
see if you can determine which hole is missing by shorting them out, then focus your attention on that particular cylinder... spark plug, intake gasket, etc , etc
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11-03-2015, 08:46 AM | #4 |
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Re: "Missing"
Even a "cleaned" plug might be defective ! Plugs are an expendable, wear out item. Always keep 1 or 2 sets of new plugs in stock. Even the CHEEPER brands of plugs work well, IF YOU USE THE RIGHT HEAT RANGE! Folks that drive with a little "GUSTO" usually don't have a "SOOTING" UP problem.
If you've ever used those old Champion Spark Plug Testers, then you KNOW the things that can go WRONG, up inside the plug, that can cause MIS-FIRING. Throw away old questionable plugs/condoms, so you're NOT tempted to use them again! Bill W.
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11-03-2015, 08:50 AM | #5 | |
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Re: "Missing"
Quote:
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11-03-2015, 02:04 PM | #6 |
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Re: "Missing"
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Beat you to it Bill ! |
11-03-2015, 07:47 PM | #7 |
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Re: "Missing"
If it has been sitting for a while you could have a stuck valve not closing all the way
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11-04-2015, 12:50 AM | #8 |
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Re: "Missing"
Maybe I should clarify: The "missing" does not happen all the time, so it cannot be a stuck valve. There is plenty of spark, so that is not the problem either. Engine runs quite smoothly most of the time, with only the occasional "miss".
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11-04-2015, 11:06 AM | #9 |
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Re: "Missing"
May be running a tad lean, try enriching it about 1/8th of a turn.
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11-04-2015, 01:11 PM | #10 |
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Re: "Missing"
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