1971 1/2 ton - Power Brake upgrade probs

[2Dogs]

Hey All,
Trying to help my neighbor with what appears to be a problem.

The truck came with front disks (all stock 2WD, original owner /forums/images/graemlins/thumb.gif). He recently added a power brake booster - a stock item/kit according to him purchased new/rebuilt from a local
parts store.

Problems/observation:
He said he believes that the brakes had more power BEFORE the power upgrade. This morning I drove it and I also think that it does not feel like power brakes. Feels very smooth and firm but not quick and powerful like I would expect.

Any advice or suggestions? Can anyone give me a part number break down on what SHOULD be there?

Details:
New/rebuilt prop valve and booster
17lbs vacuum thru the check valve
regular dot3 brake fluid (not synthetic)

Thanks!

 

[clubba68]

There is a post on here about using a 3/4 ton booster. It is supposed to help a lot according to those who have done it. I am going to be doing that swap on mine (which is non-power right now) this week sometime hopefully. I will look and see if I can find the post. If not, I'm sure someone else knows which one I am talking about.

 

[R72K5]

does booster hold vacuum after engine is turned off ? you should get 2 or three pumps of pedal weith vacuum assist after engine is off

also you should be getting 18-22 on vacuum, adjust timing a little to get 18-22

 

[2Dogs]

Yes it holds vacuum. Most noticeable when disconnecting hoses, less noticeable in affecting pedal actuation.

Sorry for lack of verbosity - I am drunk'ed /forums/images/graemlins/eek.gif /forums/images/graemlins/peace.gif /forums/images/graemlins/rotfl.gif

 

[Ryan B.]

Well it sounds like theres your problem, he's running the 1/2 ton power booster. /forums/images/graemlins/rotfl.gif /forums/images/graemlins/ignore.gif /forums/images/graemlins/deal.gif

http://coloradok5.com/forums/showflat.php/Cat/0/Board/firstgen/Number/872712/page/13/view/collapsed/sb/5/o/o/fpart/all

/forums/images/graemlins/peace.gif /forums/images/graemlins/waytogo.gif /forums/images/graemlins/woot.gif /forums/images/graemlins/bow.gif /forums/images/graemlins/pimp1.gif /forums/images/graemlins/k5.gif /forums/images/graemlins/thumb.gif /forums/images/graemlins/whistling.gif

Power Brake Booster # 54-71007


/forums/images/graemlins/grin.gif

 

[jasonkh2tg]

hmmmm you said he added a power brake booster and prop valve, Did he swap out the MC also they are diffrent units....If the MC was swaped out are you sure you bled the brake correctly...

 

[clubba68]

Thank you Ryan. That is the one that I was talking about. /forums/images/graemlins/thumb.gif

 

[2Dogs]

Thanks Guys! I'll pass the info over the fence /forums/images/graemlins/grin.gif