cucv brake questions

[maritimer]

ok so i just replaced the master cylinder on ym M1009 got thew system bled. while i did notice a considerable increase in stopping power. i am still bewildered about the front brakes. while driving down my camp road doing 10 mph if i hit the brakes the rear lock up but the front only lock if the tires are on ice. whats up with this? the calipers arnt siezed the systems bled and its got a new master, shouldnt the front brakes be grabbing sooner/harder when i stomp on the brake pedal?

 

[CCATLETT1984]

sounds like the proportioning valve is stuck. its the big silver splitter on the front crossmember.

 

[maritimer]

anyway to unstuck it ?
i dotn wanna have to replace that too LOL as it was the master and new fluid cost me just over $200

 

[CCATLETT1984]

you need to purchase some fluid from one of the vendors in the US, we can get it for $30 a gallon.
i am not sure if the blazer has the same setup as the pickup for the prop valve, I'll have to look at the TM, or wait till someone chimes in.

 

[maritimer]

yeah i was looking at that but needed brakes now got to put the beast to work next week LOL, so i sucked up the $16 per 200ML cost +taxes. next time i am buying from the US LOL

 

[ida34]

Any brake system with front disks and rear drums needs a proportioning valve due to difference in braking efficiency. It is a similar setup but they are different for different vehicle weights. The blazer also does not have the valve the M1008 does that adjusts the brakes according to how much weight is in the bed.

 

[aboonski]

ida34...I have a 1986 M1008A1 CUCV and had no idea there was an adjustable proportioning valve on my truck until I read your post. Where is mine located and how do you adjust it for a heavy load in the bed of the truck? Thanks for your info!!!!! Al Broadbent

 

[CCATLETT1984]

for the pickup. if you look on your rear axle, your gonna see a metal arm attached to a valve on the frame. it automatically limits the amount of pressure the rear brakes get based on the load in the bed. (heavier loaded will mean the frame is closer to the axle.)

 

[aboonski]

Thanks CCATLETT1984! It's dark outside right now so I'll look for the valve in the morning. Let me know if you are still interested in that Light Duty Truck Service Manual too. I hope the price didn't scare you off! Everything is negotiable! Al Broadbent

 

[Rocco]

You can get DOT 5 for $15.00 a gallon .
check out the SS classifieds.