Another booster question

[70ford1]

I am reading about all the problems of installing a brake booster on these bump trucks. My orginal I installed way back in '71. It finally quit working a number of years ago & I just never got around to changing it out. I read where the main problem was the vaccuum valve where the hose attaches. I guess this valve goes bad over time. I took the vaccuum hose off & just ran my truck without the booster though I never removed the booster. Could this valve be the only problem & after about14 years would the internal parts be so ruined the booster would not work with a new valve? I have a '76 model booster but it is the single diaphragm type & I haven't tried to install it yet. I may have the valve cover clearance problem also. A new valve can be bought but I was just wondering about the diaphragms inside--the old one is a double diaphragm & therefore is small enough for great clearance. Don't know what the failure was on the small booster but a new $25.00 valve would be just "ducky". Comments please.

[forrestbump]

The main reason you're hearing about problems with adapting power brake boosters to bumps has more to do with mismatched parts than anything else. Dents have the larger, single diaphragm vacuum boosters but they also have the cantilevered firewall brackets that lift the booster higher for valve cover clearance.

Now you're in luck as it sounds like your bump came with power brakes from the factory...correct?

You can try replacing the valve, but my suspicions are that one or both diaphragms inside your vacuum booster have ruptured. Since you already have all of the hardware attached to your truck, all you'll need to do is buy a dual diaphragm 9" diameter (or is it 9-1/2"...I forget) power brake booster for your year truck. NAPA and such sell them.

Due to the design and assembly of the vacuum booster, it's nearly impossible to disassemble, repair and reassemble them properly yourself.

1967's are the ones that tend to have the majority of issues as they're a one year only design.

[fordman]

that check valve is a filter. i am not sure that it is a one way valve or not. i always thought it was. but it is also a filter. if i have one i will check to see if it will only let air flow one way or not. but if the booster was hissing when you pushed on the brakes or the engine wouldnt run right then the diaprham was bad in the booster. and needs to be replaced. you wont run into any trouble replacing the 71 booster with a new one.

[70ford1]

No forrestbump, my truck is a 1970 f100 4x4 & there wasn't any power brakes available for the 4x4 in '70. In '71 I bought a kit made for the '70 4x4. It was an aftermarket unit & I don't know what the booster was made for. It came with a master cyl that the push rod had to be removed & replaced with the cone, also supplied, & the booster had the pedal rod & the master rod already installed. It sounds like I also need the booster mounting plate to install this booster in my truck. Is this a salvage yard item only or can it be purchased at a parts supply? Haven't looked at the new booster yet so I don't have much info for you. Will try tomorrow & see what gives. Thanks. Oh the old booster wasn't hissing when it went out. I just lost the vaccuum pressure to the brakes & they just reverted back to regular brakes. No hard pedal, just like there was never a booster installed. I made a mistake on the price of the check valve--Obsolete Ford Parts in Okla. City has it for $9.95 + shipping.

[forrestbump]

OK... gotcha! I just assumed you had the factory power brake booster.

It sounds like I also need the booster mounting plate to install this booster in my truck. Is this a salvage yard item only or can it be purchased at a parts supply?

Junk yard item to the best of my knowledge. You can ask Fordman if he's got them or post your request in the classifieds here in the parts wanted section.

...again...Sorry for any confusion I may have caused you. You know the old ASS-U-ME that I did.

[fordman]

i dont have any booster brackets. but you can get them from th ejunkyard. from any 68-72 and most 73-77 trucks have them. but when gettign them from a 73-77. make sure to get the booster and the brackets both. i would try to make sure the booster has the rod sticking out of it through the brackets. and try to stay away from the other type that have the flat bar coming out of the brackets. some of those may not fit.

[70ford1]

Thanks forrestbump & fordman---I think instead of fiddling around with adapters I will just get a unit that is made for my '70. Cardone has one that looks just like it, part #54-73515, & the application shows good for '70 F-100. If I do that I will have a re-man Cardone for a '76 F-100 that I will need to get rid of. I never tried to put it on but today I looked & yes it has the same needs as all the other mis-matches. Will have to check with the Bride & see if there is a bit of un-used cash laying around somewhere.------forrestbump, i just want to say that I have NEVER ASS-UM-ED anything wrong--& by the way if you believe that--I have some ocean front property in Phoenix for sale---Hmmmmmmmm

[forrestbump]

You're Welcome! That what all of us are here for...to help each other out.

...here I go again... I'm ASSUMING you've found the correct firewall brackets to bolt your booster to? Sorry, I'm a "Mother Hen" and just want to see that all goes well with your installation...

[70ford1]

Thanks forrestbump for your consideration---thanks to all who responded to this post, I now am smarter & learned a big bunch about my '70 4x4. I am going to buy another 9" double diaphragm booster made to fit the orginal mounting. I also decided to do a complete brake restore--new master--new wheel cylinders--new drums shoes & hardware. I need both rear backing plates but will have to find out which year models will fit. I never see them offered a NOS. Mine are worn where the shoes contact the plate. They are dished out some & tho I don't have any trouble with the brakes I may replace them. Lots of ideas---bigger than my wallet I'm afraid but hey--I can try.

[fordman]

i have a set of backing plates that will fit a 9 inch rear end.

[forrestbump]

i have a set of backing plates that will fit a 9 inch rear end.

...see what I mean about this place...refreshing ain't it!! Fordman to the rescue...AGAIN!