Volvo Owners Club Forum - View Single Post - Handbrake not working after rear caliper rebuild

ww1dm1 · Dec 20th, 2016, 10:13

Finally found the time to hit the garage!

Turns out there were two problems. One side started working properly after fully screwing in the piston, screwing it out approximately to the pads and not touching the handbrake mechanism until everything was fitted, bled and the piston was in it's normal position. I remember messing around with the handbrake arm on the caliper many times after the rebuild to make sure it's working, and now I realize that I shouldn't have. This placed the piston in a very disadvantageous position in relation to the handbrake mechanism. Even pulling the caliper arm all the way to the stop didn't clear the lash to squeeze the pads, so the handbrake didn't hold.

Sadly, this wasn't enough for the other side. It started working a little better after doing the same procedure, but it behaved oddly - pulling the handbrake slowly felt as it's engaging and then it suddenly released again, reducing the force needed to pull and going all the way again. It felt as if the handbrake mechanism squeezes the pads and then pops out of place from the excessive force. So I disassembled the caliper again to see what's up and turns out the handbrake mechanism retaining ring wasn't placed in it's groove. And it was obvious why - I just couldn't do it with the special pliers alone. It wouldn't go deep enough no matter how much I tried for some reason, as if the mechanism was unable to go as deep as it should in the bore. I ended up hammering the ring into the groove after placing it as deep as I could with the pliers. I'm still not 100% sure if all of the ring is sitting nicely in the groove (I could clearly see that the part with the holes was, but not sure entirely about the other side), but after doing this and the same procedure as with the first caliper - the handbrake works like a champ!

So basically, the x40 handbrake is not as simple as it seems. Use the reset procedure bobthecabbage posted if you messed with it after removing the caliper and make sure you put those rings all the way in if you had removed the handbrake mechanism during a rebuild.

Thanks for everyone who contributed, I'm off now for some FWD handbrake drifting on the snow!

Dec 20th, 2016, 10:13	#27
ww1dm1 What is this I don't even Last Online: Aug 31st, 2017 08:01 Join Date: Mar 2015 Location: *	Finally found the time to hit the garage! Turns out there were two problems. One side started working properly after fully screwing in the piston, screwing it out approximately to the pads and not touching the handbrake mechanism until everything was fitted, bled and the piston was in it's normal position. I remember messing around with the handbrake arm on the caliper many times after the rebuild to make sure it's working, and now I realize that I shouldn't have. This placed the piston in a very disadvantageous position in relation to the handbrake mechanism. Even pulling the caliper arm all the way to the stop didn't clear the lash to squeeze the pads, so the handbrake didn't hold. Sadly, this wasn't enough for the other side. It started working a little better after doing the same procedure, but it behaved oddly - pulling the handbrake slowly felt as it's engaging and then it suddenly released again, reducing the force needed to pull and going all the way again. It felt as if the handbrake mechanism squeezes the pads and then pops out of place from the excessive force. So I disassembled the caliper again to see what's up and turns out the handbrake mechanism retaining ring wasn't placed in it's groove. And it was obvious why - I just couldn't do it with the special pliers alone. It wouldn't go deep enough no matter how much I tried for some reason, as if the mechanism was unable to go as deep as it should in the bore. I ended up hammering the ring into the groove after placing it as deep as I could with the pliers. I'm still not 100% sure if all of the ring is sitting nicely in the groove (I could clearly see that the part with the holes was, but not sure entirely about the other side), but after doing this and the same procedure as with the first caliper - the handbrake works like a champ! So basically, the x40 handbrake is not as simple as it seems. Use the reset procedure bobthecabbage posted if you messed with it after removing the caliper and make sure you put those rings all the way in if you had removed the handbrake mechanism during a rebuild. Thanks for everyone who contributed, I'm off now for some FWD handbrake drifting on the snow!