Hey all,
So i recently bought a 99 ej9, and was told the caliper was seizing, replaced it all was good.
Then the other caliper started seizing, so i then took it off and also replaced the disc. and went and changed the disc on the other side too.
So now with 4 new pads, 2 new discs and 2 new calipers. the brakes start acting weird.
At first the pedal came loose and the brakes really soft...
But now after some messing and bleeding, the brakes are perfect for about 5/10 minutes of driving, then they start to lock on, and very strong at that, and the pedal gets very hard to press.
I have ordered new brake hoses as the current ones are pretty bad condition.
Mechanic claims it could be the proportioning valves acting as a 1-way valve?
I'm hoping the new hoses will fix the problem.
But am unsure if they will.
Has anyone else had any similar issue?

 

Sounds like there is a clog in the brake hydraulic lines.

 

Was the master cylinder.
wasnt letting fluid back in

 

Thanks for updating with your results.

 

If the master cyl or booster has been off I've seen not enough clearance at the pushrod that ended up applying the brakes when the fluid heated up. Pushrod clearance should be checked if replacing any of these parts, more likely a problem if using jobber parts.

Or, very rare could have an issue with the front brake hoses. Look at everything else first.

 

The brake reservior may have been too full and when the brake fluid heated up, it expanded, and had no where to go. I've seen it happen on bikes. That's why it's important to never fill past the "Full" mark on the reservior and to push the rubber boot back into the reservior cap, when filling the brake fluid(if the cap has a boot).