8hp timing
- Thread starter briggs33
- Start date
Most people use modified or offset keys. They may not have them for the 8HP. A bracket may work though. Just make it to allow adjustment. If you have the older model with points, increasing the gap in the points actually advances the timing a little. Very little,but nonetheless is does advance the timing.
well all im really using this engine for is just running around the neighborhood and farm so im not racing at all. so really im just trying to build a mild motor with the cheapest parts i can get but still somewhat reliable...so if you were going to build something like that what would you do?thanks
From readindg your other post, you've done most of it. A lightweight flywheel will make it rev faster.I have some 3 & 3.5hpTecumsehs with the same type of aluminum flywheels as the newer vertical engines and it's like a totally different engine. On my 5HP briggs on my build off, I'm putting an aluminum flywheel and coil from a 3.5 vertical. You may be able to find a flywheel from a smaller engine with the same taper. Then you have to relocate the holes in the coil to drop it down to the smaller flywheel. I used the milling machine on mine, but it could be done with a drill if you're careful. The plates of the coil want to seperate, so you have to have them clamped when drilling/slotting the coil. Hope this doesn't reopen the exploding flywheel thread again. Just make sure that if you had an aluminum flywheel key, you replace it with another aluminum one or re-use the same one. Don't use a steel key unless it originally came with a steel one.
The diameter of the flywheel is smaller, so you need to use the coil with the matching radius. Also you have to be sure that the magnet location on both flywheels are the same in relation to the flywheel keyway. I'm also putting on a flywheel and coil from a engine with Magnetron ignition,so I won't have to use points.
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The aluminum flywheel will weigh no where near 10 lbs. I can only speak from my own experience,but I've never had a flywheel explode or know any one who has. If you pull a lighter flywheel from another engine and run it the same speed as you ran the engine you pull it from, the chances of it breaking are far slimmer than being hit by a Greyhound bus on a logging road. Swapping out an aluminum key with a steel one or running a cast iron flywheel designed for 12HP on a 40+HP pulling tractor is another story. Why is it that anyone mentions flywheels or governors the exploding flywheel thing opens up? I have 4 engines that I have done flywheel swaps on and they have been run about 4500 rpms for years and are still running great. The only difference is quicker accceleration. If you put one on an engine making 3 or 4 times the HP, common sense should tell you it would be unsafe. Power and torque would be more likely to do damage than rpms, unless you ran it way faster than it could stay balanced. The rod is the weak link anyway. I've snapped a few of those.:thumbsup:
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ok so what i gotta do is find and aluminum flywheel. the key way on the flywheel and the magnet have to be the same spots. then i gotta take the coil expend the holes to where the coil will be about the distance of a buisness card from the magnet then im done? If anyone has some pictures that they could post that we awesome and really helpful!!