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16hp Briggs flywheels

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I wish I had some pics and measurements, but right now I don't. I was going to swap flywheels on an old 7016 with the original 326431 0190 single 16hp cast iron engine. I was trying to convert to Magnetron ignition and had what I thought was a flywheel off a 1980's iron engine with Magnetron. The bore and keyway on the later flywheel are larger than the old points flywheel. Any ideas?

I would have thought that all the 326400 cranks/flywheels would be interchangeable. Maybe the flywheel I have was mislabeled as being from a single. Did the twins use a larger crank? I was trying to avoid the shipping to Briggs for repolarization, plus I already had what I thought was the proper flywheel for the conversion. The old engine was a no ring gear flywheel, and the later one obviously has a ring gear for a gear drive starter. Tim

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I will take pics/measure the one that doesn't fit - maybe someone can ID it by seeing it.

Bob - are you saying 9hp through 16hp cast iron singles used the same flywheel? I can't speak directly for engines less than the 326400 series, but there were at least 3 different flywheels for the 32cid engines alone. I am currently looking at the Briggs parts breakdown for the 326400 series and there are 3 part numbers listed based on type number. It clearly shows non-ring gear and ring gear style. Now, they may all physically interchange from one engine to another, but they certainly won't actually make the engine work when swapped.

There must be 2 flywheels for points igntion - 1 with a ring gear, one without. The one without a ring gear has no magnets for a stator type charging system. That is what I just took off a 326431-0190 in a 7016. I assume all ring gear styles have magnets for a stator type charging system. Interestingly, the parts breakdown only mentions a 10 amp flywheel for use with points. I assume they mean a 10 amp stator type charging system? What about the non-ring gear flywheel for use with S/G?

There appear to be 2 for the later Magnetron igntion also - 1 with a ring gear, 1 without. The ignition magnet polarization is opposite from points to Magnetron igntion, so you can't just swap them without making other changes.

Obviously an engine with a gear drive starter needs a flywheel with a ring gear. Again, it can likely all be converted from S/G to gear drive or vice/versa, but not by just swapping flywheels.

I just dug out 2 more flywheels from other parts engines. One is from a 326437 0333-01 8009291 - which is a points style engine. The other is from a 326437 0720-01 8401301, which has no provisions for points, and is Magnetron. Using the Briggs flywheel polarization tool, they have opposite polarization of the ignition magnets. The later one for Magnetron matches the polarization of a 5hp flywheel. The iron singles with points are the only modern Briggs with the magnet being "opposite"(north, I think it is). If we get back to the 2 digit or lettered engines - I don't know anything about them.

I don't mean to come off as a know it all or to knock your response. It's just that I am trying to clear up/find out how many variations there are and what the variations are because they are not all the "same", or even interchangeable as a single part of the engine. If anyone has any more info, please post it. Thanks, Tim

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Bob (BLT) is probably correct in his statement about the C.I. single family 22xxxx through the 32yyyy flywheels; all use the same taper and key-way spec: " 9 thru 16 HP CI engines use the same wheel. " For these engines, they always had magnets on the outside of the flywheel for the magneto; be it points or Magnetron.

My guess is this flywheel you're trying to use is from a different model series and incompatible thereof. Yes, there were variations of flywheels of the 9-16 HP series over time: some with internal magnet rings for the alternator, pre-1981 year points magnet polarity, later versions with the ring-gear option for a gear starter, post mid-1981 magnet polarity for Magnetron. So when doing the historical leg-work P/N search for these variations, it could become somewhat mind-numbing. I believe if a ring gear F/W is being used on an original starter-gen type of engine, it should still clear the blower housing without issue.

So, distilled down (IMHO), you are trying to put the wrong model series flywheel on this family of engine.

Tom (PK)

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You can reuse your old F/W by sending it in to Briggs and have it re-polarized for Magnetron. They will do it N-C and send it back to you.

I could think of at least a half to a dozen combination of F/W's or more that were available depending on a given application. And only Briggs engineering has that.

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OK, more info. Thanks for the discussion on this. I would send it to Briggs - I have done it in the past. It's just that I had a flywheel laying around that I thought would just easily bolt on. So - it's my father who is actually doing the work. I went over there today to inspect it myself and found out 2 very important things that he had overlooked. The ID of the flywheel isn't wrong - the Magnetron flywheel with a ring gear was hitting the coil bracket and not allowing it to slide all the way onto the taper - therefore he thought the ID was too large. Second, my question about the keyway being 1/4" and not 3/16". I went back and dug out the parts engine this flywheel had come off. Looking closely at the crank and the flywheel, this engine has been damaged and modified. It must have had a loose flywheel and chucked out the original keyway. It has been opened up to 1/4", but each part still shows a scar of a chucked out key. He was right about it being bigger - I just couldn't understand why at the time. Now, on to the coil mount bracket. Briggs only has one part number listed in the current breakdown, and I have not dug out any old paper books to get part numbers - it doesn't really matter. There are at least 3 distinct variations on coil brackets. I dug around and came up with 2 more besides the original one to the 7016 that I am trying to convert to Magnetron. I do not know for sure what the other 2 came off of. One was literally found in the dirt in a pile of parts a while back, the other was just in a box of my misc stuff. They are all 3 made a little different, with 2 of them having clearance for the ring gear flywheel. A ring gear flywheel is about 3/8 - 7/16" thicker than a non-ring gear style. I think the points style bracket could easily be clearanced for use with a ring gear flywheel. Tried them all on the parts engine I have at my house. See the pics. Does anyone ever remember a small engine with a stepped flywheel key? Was that a Tecumseh that had a stepped key? I think it was from 1/8 up to 3/16", rather than 3/16 up to 1/4". I don't want to trash this one flywheel, but with a wrong key, it doesn't do much good on anything other than the crank it is matched to. But, it won't use the proper hardness key, so there is a risk of damage if something went wrong there. I will get him the Magnetron style bracket tomorrow, so we will see how that goes. Thanks again for your input, Tim



























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