phsautomotivesalsphsautomotivesals drum brake overhaul
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Many times when we first attempt doing something we don’t know how to do certain things. Or we forget or don’t remember if we have not done something for a while. I have listed some things to do when working on drum brakes please let me know If I have forgotten anything.
S. Salisbury
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Couple of things to think about when working on brakes.
1. Some ones life may hang in the balance if you do a poor or second rate job.
2. If you do not think a part will work right replace it.
3. Always put in new brake shoes, if the hardware has problems replace it and if the wheel cylinder is worn or pitted replace it. And last but not least inspect the hose for wear and cracks.
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• Inspect wheel studs and lug nuts(replace if necessary)Notice 1 stud shorter then the rest
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Remove drum• If first time drum has been off may have to
remove clip on the studs
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• Some drums will slide right off, others may have to be hit with a hammer to free up. Some imports have two holes to install a bolt in to force off tighten each with equal pressure.
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• Some drums may need the star wheel backed off if all else fails hook up a brake drum puller. Before you get too crazy make sure the parking brake is off.
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• inspect drums for grooves and out of roundness, mic and check for oversize
• Inspect shoes and brake parts
• Inspect brake lines and hoses
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• any broken or worn parts should be replaced
• Check for leaking wheel cylinder
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• If needing replacement clean the brake assembly then remove all parts
• CAUTION do not blow off with compress air
• Use a Vacuum system designed to clean the brakes or a low pressure washer to clean the brake assembly.
• note how it was all installed take a picture or find page in service manual that has a good picture of all the pieces.
• clean backing plate with wire brush
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• contact points on backing plate are called a shoe pad. They should be filed flat to prevent shoes from hanging up in deep grooves or better yet just replace the backing plate. (4-6 per backing plate)
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• make sure you remove the wheel cylinder bleeder screws and clean the passage in it. No sense rebuilding it if froze in the cylinder
• use brake fluid as a honing fluid
• do not hone over .006
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• Lightly coat the wheel cylinder cup and pistons and reassemble and reinstall on backing plate
• clean backing plate and lube shoe pad with a thin coat of grease
• install new brake shoes
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• make sure springs are not stretched
• make sure the sharp points on the star wheel are not worn and the adjuster that comes in contact with star points is not worn
• reinstall all parts
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• readjust shoes to fit drum, use a brake drum gauge if you have one and replace brake drum
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• if drum will not go on, back off parking brake adjustment
• sometimes someone will tighten up the parking brake before they check the adjustment of the service brakes.
• make sure shoes are adjusted so a slight drag is felt
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• bleed brakes until clear and free of bubbles
• brake fluid absorbs moisture and collects dirt, needs to be changed ever so often
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• if bearings are removed and are not sealed be sure to clean and repack bearings and replace the grease seals.