Re: 502 Refurbishment
Posted: Tue Jan 12, 2016 10:42 pm
Now reinstall the chain, sprockets, lower shaft and spacers. Install the idler sprocket and tighten the chain. Rotate the shafts and insure the chain moves across the sprockets smoothly.
These gearboxes are known for leaking. Here are a few tips to help:
- When you scrape the gasket off the aluminum gearcase, then follow up with a light grinding of the surface. This not only cleans all gasket material off, but it levels out the metal around the bolts holes that tends to get pulled outward.
- The holes in the covers also tend to get distorted. Set your covers on a vice and lightly pound out around the holes. This gives the cover a little spring when installing it.
- If the bore that the bottom bearing goes in to is loose, use Loctite bearing retainer on it to take up the clearance.
- Use a thin cork gasket if you are making your own. Using a thick gasket moves the seal farther away from the shaft on the lower sprocket and there is not much surface to spare when it's assembled.
- Put a bead of Permatex on the aluminum with putting it on a little thicker at the bottom circle.
- Install your gasket as shown.
- Put another coat of Permatex on the gasket again a little thicker at the bottom circle.
- When you put your top cover on, have the aluminum spacer against the top gear and center the top hole in the cover around that spacer.
- Put a heavy bead of Permatex side to side on the bottom edge of the top cover where the bottom cover overlaps.
- Install bottom cover.
- Hand tighten bolts and let Permatex set up for several hours. Then retighten cover bolts.
Then press your bearing blocks on with new bearings.
These gearboxes are known for leaking. Here are a few tips to help:
- When you scrape the gasket off the aluminum gearcase, then follow up with a light grinding of the surface. This not only cleans all gasket material off, but it levels out the metal around the bolts holes that tends to get pulled outward.
- The holes in the covers also tend to get distorted. Set your covers on a vice and lightly pound out around the holes. This gives the cover a little spring when installing it.
- If the bore that the bottom bearing goes in to is loose, use Loctite bearing retainer on it to take up the clearance.
- Use a thin cork gasket if you are making your own. Using a thick gasket moves the seal farther away from the shaft on the lower sprocket and there is not much surface to spare when it's assembled.
- Put a bead of Permatex on the aluminum with putting it on a little thicker at the bottom circle.
- Install your gasket as shown.
- Put another coat of Permatex on the gasket again a little thicker at the bottom circle.
- When you put your top cover on, have the aluminum spacer against the top gear and center the top hole in the cover around that spacer.
- Put a heavy bead of Permatex side to side on the bottom edge of the top cover where the bottom cover overlaps.
- Install bottom cover.
- Hand tighten bolts and let Permatex set up for several hours. Then retighten cover bolts.
Then press your bearing blocks on with new bearings.