drum brakes locked-up

any ideas on why a typical hydraulic drum brake trailer would be locked up ? Not all wheels, but most.

Re: drum brakes locked-up

when you park your trailer you should back farther than you need to, then pull up, to release the brakes. one of the problems with drum brakes.

Re: drum brakes locked-up

I would be looking at corrosion in the wheel cylinders.

Re: drum brakes locked-up

A few possibilities --- some already stated--

- Not fully releasing the surge actuator will keep the linings in contact with the drum faces and they will rust into place. Pulling forward slightly before parking the trailer will release the surge master cylinder and prevent this.
- Old and worn linings will develop rust underneath the linings and in extream cases lock the drum up
- Corrosion on the wheel cylinders keep the linings from retracting resulting in the linings rusting to the drum.

Pulling forward will not always release a frozen drum but backing up will usually work. the free backing design of the drum brakes forces the linings to retract when backing up.

Re: drum brakes locked-up

The trailer I have now has hydraulic surge brakes rated for 6000 lbs that need completly rebuilding. I'm thinking about converting them to electric brakes. Is this feasible & if so, are electric brakes better then surge & what is involved in converting them over to electric? They are 10" brakes now & I will be keeping them at 10".

Re: drum brakes locked-up

I don't think you want electric brakes on a boat trailer, especially if used in salt water. Chance are that the keepers/pin ( weakest link in the system) that holds shoes to the back plate are probably toatly rusted away and the shoes are slipping inside the drum.