Warning: '86 e-350 master cyl. Swap unsafe
UDATE FOR ANYONE DOING THE '86 E350 MASTER CYLINDER UPGRADE w/ REAR DISK BRAKES: taking the O-ring out of the proportioning valve will not make this master work with 4 wheel disk brakes! this is a major safety issue.
This brake master is not designed to work with rear disks. this master sends more pressure to the rear and almost none to the front. doing this heats the rear fluid because it is all channelled into one main line. this causes damage to the master and cover gasket.
Further; the top clamp interferes with the vacuum brake booster and creates uneven pressure on the lid gasket. this causes the rear brake reservoir (smaller, front reservoir) to empty as fluid returns from the lines and runs along the bottom side of the cover. it then leeks out through the gap between the gasket and the reservoir. eventualy the reservoir empties and begins to plunge air into the lines. since the front brakes do not work correctly with this master, and the rear empties, you loose brakes COMPLETELY. luckily i have a 5 speed and the air pressure was enough to come to a slow stop with downshifting and get home without crashing.
PLEASE DO NOT ATTEMPT TO USE THE '86 E-350 BRAKE MASTER CYLINDER WITH REAR DISK BRAKE CONVERSIONS.
93YJ 350-465-205, D60 and 14 Bolt, 40's http://www.jeepforum.com/forum/f22/yj-rustoration-1327569/