Brakes pulling to right

[rob_mitch 0 1 Cars]

I have just upgraded front brakes on my 1.9 to  266 mm dia discs with 208 Bosch calipers and a larger 405 M/C.  The car, converted by a previous owner to a clubman rally car, was actually fitted with Bendix 1.6 calipers rather than Girling calipers.

 

I tried a variety of standard and uprated brake pads but could never get the front brakes to lock consistently before the rear, even with brake bias valve set to minimum for rear brakes.  Also replaced front caliper slider pins but no improvement.

 

With new setup, car pulls consistently to right under mild to moderate braking, on heavy braking the right front locks up and the car then tracks straight!

 

I have bled the brakes multiple times, swapped the front pads from side-to-side to no effect.  Both caliper mounts have been cleaned out, new pin rubbers and re-greased (silicone).

Yesterday I discovered the lower slider pin on left was quite sticky, it would rotate OK but not slide.  I have re-cleaned bore-hole on mount and it now slides OK.  But car still pulls to right and right brake locks up.

 

Any suggestions for possible solutions gratefully received.  Both calipers are new (refurbed) units from BrakeParts Int, although from different suppliers.  I am starting to suspect the problem may be hydraulic, so looking now at trying another left caliper and possibly another brake hose.

[DamirGTI 342]

Likely bad rubber flexi hose on that side , can cheek by crack opening the bleed nipple on the caliper immediately after good 10-15 hard-fast brake pedal pumping - if it squirts the brake fluid when you crack open the bleeder , even slightly , it's the hose .. if it just drips slowly , not the hose but rather the caliper piston then , ie. square cut seal not doing it's job as supposed to .

 

Brake hoses , best to replace all of them even if it's just one gone bad .

 

Brake caliper , can buy complete rebuild set/kit and refurbish it ... it really isn't hard/complicated job .

Myself personally , found the "new" rebuilt calipers being bad often , badly/incorrectly rebuilt with cheap material and poorly cleaned up ... cheaper unknown brand calipers are the worst , they're collecting them in bulk and sending to be rebuilt in eastern EU or usually China .

 

If buying new ones stick with well known brands : TRW , ATE , Bendix , Bosch ... avoid cheap unknown brands .

 

D

Edited September 1, 2021 by DamirGTI

[PhilNW 44]

Have you thought of nipping down the local MOT place and checking the brakes on their brake tester to see how much effort is being applied to each wheel

 

Are the brake hoses braided steel or rubber?

Edited September 2, 2021 by PhilNW

[rob_mitch 0 1 Cars]

Thanks for the replies. I did the hose test last night, no sign of any pressure left over.

 

Hoses are Goodridge, probably replaced about 10 years ago for rally conversion.

 

I have removed piston from original calliper which came with calliper mounts, piston looks like it will be re-usable after a cleanup.  I am going to local dealer to see if I can get a genuine re-build kit.

 

Yes I agree about using local garage who do MOT if I cannot fix this myself, hopefully rebuilt calliper will do it.

 

 

[DamirGTI 342]

Spanish "Autofren/Sensia" and "Fenkit" caliper rebuild kits are good .. been using them for a while now and , no complains .

 

Though , i prefer TRW or ATE stuff when/if i can get some .. if not , the above will be fine (Bosch boxed kits now usually contains "Autofren/Sensia" parts , so just repacked) .

 

Would really do the lot , complete kit with the new piston .. not much price difference to justify not to ... as i rebuilt some by reusing old pistons which looked and seemed god visually but , few months after had to do it again as there was clearly something wrong with the piston .. probably deformed due to overheating .

 

Thoroughly cleanup the caliper slider bores on the caliper holder and wash of with brake cleaner , also i'd fit new slider pins , with some silicon grease .

 

D