Timing TDC, rough idle
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Timing TDC, rough idle
84 300 6cyl, the engine is about a 4year old rebuild and no visible oil burning. Lately it has been idling very rough and doesn't clean up until about 1200rpm then runs fine after that. I did all the usuals, changed plugs, wires and cap and rotor and set to factory timing. Still rough idle so I rebuilt the carb, no change.
My question is how to check if my timing chain jumped teeth? I'm guessing by pulling the valve cover and getting no.1 cylinder to exact tdc by verifing the valves are both closed on the compression stroke then my timing mark on the balancer should point to the 'zero' mark on the little timing 'guage'??? Short of pulling the timing chain cover and checking the marks on the gears, is this the most reliable method?
Has anyone ever used a vacuum gauge to set their timing rather then by sound or light?
My question is how to check if my timing chain jumped teeth? I'm guessing by pulling the valve cover and getting no.1 cylinder to exact tdc by verifing the valves are both closed on the compression stroke then my timing mark on the balancer should point to the 'zero' mark on the little timing 'guage'??? Short of pulling the timing chain cover and checking the marks on the gears, is this the most reliable method?
Has anyone ever used a vacuum gauge to set their timing rather then by sound or light?
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Joined: Oct 2004
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I believe the 4.9 uses timing gears rather than a chain. Very unlikely for it to jump time and still run. Take a look at my reply to "one more time on timing" post for information on timing the engine for peak performance and mileage.
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