Misfire

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Alex'n'Ane
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Misfire

Post by Alex'n'Ane »

The first cylinder on my engine isnt firing, it was rebuilt recently, and has been run in. So far have changed the plug, leads, dizzy cap, and rotor arm. There is a spark at the plug when its shorted against the block, and the cylinder has good compression. Any other ideas or possible problems??
___Anne___

bmcecosse
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Re: Misfire

Post by bmcecosse »

How do you know it has 'good compression' - let's see the figures ! Are the valves opening? Otherwise don't see how with spark and new plug and compression - it can't be firing!
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///Col-Col\\\
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Re: Misfire

Post by ///Col-Col\\\ »

ive compression checked it multipul times. and regapped the tappets. so the valves are going up and down
bmcecosse
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Re: Misfire

Post by bmcecosse »

Bad plug ? Try another!
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beero
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Re: Misfire

Post by beero »

Yes, swap the plug with no 2 and see if the misfire moves. If not then swap the ht leads and see if it moves. If not it could be your dizzy cap.

bmcecosse
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Re: Misfire

Post by bmcecosse »

Or - water leaking into the chamber...........
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IslipMinor
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Re: Misfire

Post by IslipMinor »

What were the results of the compression test? What are the compression pressures and is No.1 lower than the rest?

What is the engine spec? Does it have unleaded valve seats and/or bronze valve guides? Does it misfire all the time? Did it run correctly after the rebuild? If so how many miles has it done and did you re-torque the head after it was first run and again after around 1000 miles?

Is there any sign of water in the oil or oil in the cooling system?
Richard


bmcecosse
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Re: Misfire

Post by bmcecosse »

Maybe the water pump by-pass has been blocked off......... :-?
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IslipMinor
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Re: Misfire

Post by IslipMinor »

bmcecosse wrote:Maybe the water pump by-pass has been blocked off......... :-?
You never know!!
Richard


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