Question for anyone who is familiar with them. My buddy's bass boat trailer has a problem with the hydraulic braking system. When he stops the trailer brakes try to lock up but it is a repeated on-off type problem. by on-off, i mean it does it everytime he goes to stop but the brakes lock up on-off with a "pow-pow-pow-pow" type problem. it beats the hell out of the boat and tahoe. we have checked and rechecked the brake system including the tongue. it does it even with the slightest braking pressure with or without boat. one thing we did notice is it didn't do it last night after we pulled the boat out of the water until 15 or so minutes later. the drums are not cracked or out of round and the wheel cylinders and shoes are fine. any clue as to what could be causing this shit?

5/17/2006 6:29:10 PM

Is this a system that has a brake line that runs to the tongue and when the vehicle is braking, the part where the ball sits pushes up and backward causing an increase in the line pressure?

5/17/2006 8:54:04 PM

Yeah. The master cylinder is on top of the tongue and has a bellcrank linkage with a nice thick spring on it, I believe. You can usually adjust the spring pressure to vary the rate/intensity of the application.

5/17/2006 9:05:55 PM

^ what he said, there is a threaded rod in the tongue to adjust the braking pressure to the trailer weight most of the time it doesnt need adjustment, the braking force should balance itself out. and the trailer catches up to the truck, the brakes are applied harder, and as it approaches the truck speed, it releases the brakes, you could have broken spring, so the the force is not damping, its just freely sliding back and forth in the tongue

5/17/2006 9:39:21 PM

i'll check that again but we did check everything in the tongue several times and everything seemed to be good. like i said, this thing will do it even without the boat on the trailer which really puzzles the hell outta me.

5/18/2006 6:48:37 AM

without the weight of the boat, the brakes should't even come on, i'd check that spring one more time

5/18/2006 8:43:49 AM