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4 hp Briggs Horizontal engine

I think the flywheel key may be partially sheared, causing the timing to be off. I have backfire through the carb. This is a wood splitter that I over-worked recently.

I installed a new solid state magneto and have good spark.
Question: How do I replace the key? Are special tools requited?

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On your flywheel there should be 2 holes threaded on the top area & the retaining nut in the centre.
remove the centre nut completely, then get a flat piece of steel bar (about 6" long x 1/2" thick x 11/2" wide) drill 2 holes (clearance holes) at the same distance as the ones on the flywheel.
then drill one in the centre about 1/4" dia.
Get two bolts that will fit into the 2 threaded holes & pass then through your newly drilled bar.
Place a ball bearing on the centre hole & tighten your 2 bolts inwards.
When they both start to get tight tap the flywheel with a hammer & tighten futher on the bolts.
The flywheel should now come loose.

Posted on Nov 27, 2008


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