This article shows the steps to replace your worn out flywheel ring gear on your WWII G503 Military Jeep (Willys MB or Ford GPW)
![This article applies to both Willys MB and Ford GPW WWII Military Jeeps](images/appliesto_W-f.jpg)
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1. While into disecting your project, many times you come across a weak starting issue. In many cases, it is due to a flywheel ring gear being worn out. Here you see a perfect example where the flywheel ring gear are nearly completely worn out. |
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2. Replacing the ring gear is not a difficult task. Here we show the new 97 tooth ring gear with the new replacement. |
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3. Place the flywheel on the 4x4 block of wood. Heat the ring gear for about 2 passes all the way around the ring with the machined side up. This will expand the ring from the flywheel. |
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4. Turn the torch off, and quickly tap the ring from the flywheel. This should only take a couple of taps around the ring and the old ring gear should fall off. |
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5. Turn the flywheel over with the machined side down, then place the new ring gear on the flywheel (still on the 4x4 block), the ring gear should be a little short of fitting on the flywheel. Now heat the the ring gear up with a torch (as you did before taking it off). The ring gear will expand enough after you take about 2 passes around the gear. |
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6. Turn the tourch off and grab your punch and hammer and tap the ring gear evenly around the flywheel. |
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7. After tapping the new ring gear on the flywheel it should cool off and tighten up around the flywheel.... Looks good! |
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8. Wow, what a difference when you compare the old worn ring gear to a new one! Looks great, and now the starter will hit the gear terrific. |
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9. Here you see the flywheel installed on the crank and looks great, ready for the clutch plate to be installed. |