BIGWIG74:
im having problems with a slow releasing hand brake on a 06 cf85 8x4 ive changed the 4 way valve/air processing and the relay valve under the nearside step.its ok once it does release just taking a few moments more than our other trucks,if anyone has any ideas it would be appreciated
I had this self same problem on an ERF EC11, we replaced the multi-circuit valve, the air dryer, had the compressor to bits, the hand brake valve, drained and cleaned the tanks and the airlines, checked pressures at various points - It was driving me crackers. Next we replaced the R6 relay valve on the crossmember in front of the drive axle.
Had already tested the non-return valve the feeds this, and it seemed ok. On a closer inspection, we took it to bits and found a ‘mushroom shaped’ rubber seal that was mis-shapen, This was working on a hit & miss basis - replaced this and all was fine
All that grief, head scatching, swearing & cussing for a simple little valve 