8n runs rough

steve mower · Nov 16, 2014

My '51 8n starts and has good power under load, but stumbles during fast or slow idle. Also runs rough when mowing under light load, like when going downhill. New points, cap, rotor and plugs didn't help. Rebuilt carburator 2 years ago and was running great-this stumbling is a recent development. Weird thing; idles better when idle screw is closed. I have never been able to time it, there are no timing marks visible. I just rotate distributor until I get the best engine sound at high rpm. I've had the carb apart and cleaned all ports and checked float operation. Any ideas?

old · Nov 16, 2014

Did you use a small wire or other such thing to clean out the passage ways or just air and or carb cleaner?? If you did not poke a wire into them good chance one has some dirt or rust still in one

Tom N MS · Nov 16, 2014

Still blockage in carburetor -- odle screw closed
enriches the mixture....

steve mower · Nov 16, 2014

I used just air. I'll dismantle and soak in carb cleaner, then chase ports with copper wire. thanks for the advice.

old · Nov 16, 2014

After poking th passage ways spray carb cleaner spray in to remove with you loosen up. I use a torch tip cleaner toll to do that job. Many size wires and works well and also easy to keep on hand for carb jobs

8n runs rough

steve mower

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old

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Tom N MS

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steve mower

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old

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