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dsraven · 06-14-2023, 10:24 AM

when adjusting drum brakes on a vehicle that has sat for awhile and possibly has rust on the drum surfaces it is best to first remove the drums and clean them up, check the wheel cylinders for obvious problems by pulling the rubber boot back and physically looking into the bore where the piston sits looking for leakage contamination rust etc, check the backing plates for wear at the shoe contact points (there is actually lube for those spots), check to ensure the park brake cables are operating properly and full release is happening, check the park brake lever on the shoes where it pivots to ensure it is not stuck or sticky and possibly lube that spot, check/ensure the park brake cable adjuster is operational, check/ensure the star adjuster wheel is free and the ratchet mechanism or spring that holds the star wheel in position is operational, check/ensure the springs are in good shape and not overstretched or mishaped. check the flex hoses to each wheel out front and the one from the frame down to the rear axle. check the steel lines from the master cylinder out to the wheel end for each wheel to ensure they are in good shape and no crush points or rusted spots that would affect operation, check the bar that connects the shoes to ensure it is located correctly and has the spring, check the brake shoe retainers for deformity and integrity.
at this point you could install 3 of the 4 drums and have a helper step on the pedal slightly (i say slightly so a full stroke isn't made which would possibly push the wheel cylinder pistons out of the bore) while you check for operation of the brake on the one with no drum. do this for each wheel. the wheel cylinders should push out on both ends of the cylinders but remember one spring is stronger than the other so it will want to push one out and allow the other to sit idle. if you try moving the brake shoes so the pistons are forced to move through the cylinder this will help you see if both the pistons are moving.
keep us [osted on what you find. pics are really helpful

06-14-2023, 10:24 AM	#47
dsraven Registered User Join Date: Nov 2010 Location: calgary alberta Posts: 7,858	Re: Moody's Utah 58 Apache when adjusting drum brakes on a vehicle that has sat for awhile and possibly has rust on the drum surfaces it is best to first remove the drums and clean them up, check the wheel cylinders for obvious problems by pulling the rubber boot back and physically looking into the bore where the piston sits looking for leakage contamination rust etc, check the backing plates for wear at the shoe contact points (there is actually lube for those spots), check to ensure the park brake cables are operating properly and full release is happening, check the park brake lever on the shoes where it pivots to ensure it is not stuck or sticky and possibly lube that spot, check/ensure the park brake cable adjuster is operational, check/ensure the star adjuster wheel is free and the ratchet mechanism or spring that holds the star wheel in position is operational, check/ensure the springs are in good shape and not overstretched or mishaped. check the flex hoses to each wheel out front and the one from the frame down to the rear axle. check the steel lines from the master cylinder out to the wheel end for each wheel to ensure they are in good shape and no crush points or rusted spots that would affect operation, check the bar that connects the shoes to ensure it is located correctly and has the spring, check the brake shoe retainers for deformity and integrity. at this point you could install 3 of the 4 drums and have a helper step on the pedal slightly (i say slightly so a full stroke isn't made which would possibly push the wheel cylinder pistons out of the bore) while you check for operation of the brake on the one with no drum. do this for each wheel. the wheel cylinders should push out on both ends of the cylinders but remember one spring is stronger than the other so it will want to push one out and allow the other to sit idle. if you try moving the brake shoes so the pistons are forced to move through the cylinder this will help you see if both the pistons are moving. keep us [osted on what you find. pics are really helpful