Inconsistent Braking - 76

[Hokie93]

I've got a 76 with stock brakes (disc / drum) and a strange braking issue. Typically for the first 10 or 20 miles I drive (often the entire trip), it feels like there's very little braking power. Feels like a 300lb leg press at the gym to get her to stop. If I really jump on it she'll lock up - but that might require both feet. After driving a while, she stops like she should. I've checked the fluid, level is good, no leaks. Any ideas?

 

[Viperwolf1]

Check the vac booster and line for vac leaks.

 

[zeeman1]

Check the vac booster and line for vac leaks.

x2 on that, I would look for leaks in the vacuum line.

 

[blubuckaroo]

Hokie93,
Factory power brakes?
I've had that happen several times to my '77. It seems like if you hammer the brakes really hard then they start to work properly. Do you also notice that when you apply the brakes while idling that the engine runs rougher? Time for a new booster. I've replaced mine four times since I bought it new. I don't think the diaphram is leaking but the booster valve must get hard and leak. I've found the best way is to get the whole booster/master cyl assembly. That way you shouldn't need to mess with the pushrod length. Got mine from partsamerica and it has a lifetime warrenty.

 

[Hokie93]

Hokie93,
... It seems like if you hammer the brakes really hard then they start to work properly.

That's exactly it. Thanks!

 

[RT]

I went though the same thing , getting new boosters , messin' with bigger piston brake calipers , but I just couldn't get it consistant .

I do know a guy that says his stops well enough without power assist that he hasn't bothered with the hydroboost sitting on his bench . I think he said he's just got a camper special master on it . I could never get my non boosted brakes to work that well .

I finally went hydroboost myself , and it's been very consistant , and not touchy like I thought it would be .
The first year I just used the stock Tompson pump , and probably would still be using it if not for the F-150 box I swapped in .
It was a easy swap , didn't even undo a brake line . Just used the stock booster bracket , made up a spacer for the super duty booster , and used Aeroquip type fittings so I could make the hoses the length I wanted them .

Over the years I messed with trying to get the vacume stuff to work , this cost less over all . I got lucky with finding the booster at a wrecker for $80 , and the hoses/ fittings ran another $80 . Could be cheaper without using the Aeroquip type stuff . Just made it conveinent for me .

If your up to it , it's not a hard swap .

Good luck .

 

[Hokie93]

... Time for a new booster. I've replaced mine four times since I bought it new. I don't think the diaphram is leaking but the booster valve must get hard and leak. I've found the best way is to get the whole booster/master cyl assembly. That way you shouldn't need to mess with the pushrod length. Got mine from partsamerica and it has a lifetime warrenty ...

Is the consensus to skip just replacing the booster, and do the master cylinder as well? This booster - http://www.partsamerica.com/product...1C&MfrPartNumber=5473220&PartType=250&PTSet=A - from a local parts shop claims to be OEM with the rods pre adjusted. Any one have success with one of these?

 

[NicksTrix]

you've got a new master on there hokie.

 

[blubuckaroo]

Hokie,
That's the one but I got mine complete with a master cyl. I think it cost $170. If it's over $50 and less than 20 lbs shipping is free. With the complete booster/master it was right at 20 lbs and they charged me shipping.
I put it in on Sunday. I had forgotten what it was like with good brakes and just about kissed the windshield!

 

[DirtDonk]

Sorry, but I just have to hijack for a second. I just noticed your (new?) avatar bluebuckaroo and just had a serious flashback! My first motorized 2-wheel conveyance was a '66 CT200 (Trail 90) just like in the pic. Nothing quite like getting 201 miles per gallon when you're 15 and on a budget. Even if gas was only 60 cents a gallon!
Man, that's some seriously LOW off-road gearing!

Thanks. That flashback was worth it. Now that I'm back in the "now", you can have your thread back

Paul

 

[blubuckaroo]

Sorry, but I just have to hijack for a second. I just noticed your (new?) avatar bluebuckaroo and just had a serious flashback! My first motorized 2-wheel conveyance was a '66 CT200 (Trail 90) just like in the pic. Nothing quite like getting 201 miles per gallon when you're 15 and on a budget. Even if gas was only 60 cents a gallon!
Man, that's some seriously LOW off-road gearing!

Thanks. That flashback was worth it. Now that I'm back in the "now", you can have your thread back

Paul

Paul,
I regularly ride a 1970 CT 90 Trail. Very useful for picking up parts and hardware as well as being my hunting vehicle once I get to camp.

 

[DirtDonk]

Better still! Yours has the High-Low range switchable tranny so you don't have to take a half-hour out of riding while you change your rear sprocket for low-range and then do it all over again when you need the street gears. I was always jealous.
Of course, you probably "only" get about 140 mpg, but with almost double the power of the older pushrod engine like mine, it was a fair trade-off.
Good choice.

Paul