Brakes. WTF am I not doing / doing wrong?

[exp500]

OP has been fighting Chineezeeium parts I think. His master/wheel cylinder sizes are within usable ranges. I've been following/suggesting for a couple months, Something isn't right and he hasn't found it. Hell, could be brake shoes in wrong positions. I'm not there.
As I suggested above- doing something the same way multiple times and expecting different results........

 

[96-2D-Hoe]

I think part of the problem was that I expected to be able to get a decent pedal. I've followed service guidelines and haven't got one. But I'm far from the only person who has shit brake pedal/brakes in these trucks. It's a fairly common problem and I think most people end up settling. I didn't want to settle.

The Duralast MC's from autozone are junk, and using the Motive did not help matters damaging 2 MC's.

The Delco I just installed came without blanking plugs that were mentioned in the instructions. I used a couple I had left over to bench bleed it. It acted very differently than any other I have had. I was also getting reoccurring bubbles while bleeding the Delco same as I got with one from AZ that I returned. If I was more gentle with it I didn't get them. I did the bench bleed overnight in my kitchen and didn't rush it. I suspect this Delco MC may not be 100%. I put it in anyway and hoped for the best.

Now I need a brake booster. I could possibly maneuver the MC out of the way but I'll probably just remove it and check it again with a bench bleed.

I also buy brake fluid by the gallon and I've used 4 so far.

I pump the pedal as outlined in the service guidlines pump and wait 10-15 seconds.

I'm way more sick of this issue than any of you I can assure you.

Right now I need to buy the brake booster and get that done. I'm not sure I will continue my 'quest' for the perfect brake pedal but who knows. I was hoping I could get it back to how it was when I bought it but I obviously haven't achieved that yet.

Thanks for all of your suggestions and advice.

 

[exp500]

You may never get a perfect pedal with these- maybe 1/2 inch lower than it should be, But it better be a firm pedal. The only way to drastically improve the pedal is to install the largest diameter master you can find- somewhere in the 1-5/16- 1-3/8 dia range. that short strokes pedal( I think you are close to this now) . Next is wheel cylinders- somewhere in the 7/8-1-1/16 size... but then the proportioning valve is probably wrong and rears lock before fronts( I like adjustable proportioning valves). ABS confounds this whole scenario, as it is calibrated to a small range of master sizes. Larger master increases amount of foot pressure required- thats why everyboby tries the hydroboost brakes because if you need more brakes raise the pump pressure. It's a great system if maintained.

 

[OR VietVet]

Personally I think since you know you need a booster you need to do that and make sure all air is out and make doubly sure any adjustments are correct and see where it goes from there. The booster alone effects pedal feel.

 

[iamdub]

Maybe I missed it, but have you replaced the flex hoses? I'd imagine the brakes in my '02 S10 to be very similar to the C/K trucks of this generation. I first converted the rear to discs and that made a notable improvement in the pedal response. Then I replaced all the hoses with braided stainless and that made a huge improvement over that. Then, I swapped on a Blazer MC for even more improvement. The crown jewel was when I swapped to hydraboost. There was no wasted travel in the pedal and it was solid when you stood on it.

 

[96-2D-Hoe]

Maybe I missed it, but have you replaced the flex hoses? I'd imagine the brakes in my '02 S10 to be very similar to the C/K trucks of this generation. I first converted the rear to discs and that made a notable improvement in the pedal response. Then I replaced all the hoses with braided stainless and that made a huge improvement over that. Then, I swapped on a Blazer MC for even more improvement. The crown jewel was when I swapped to hydraboost. There was no wasted travel in the pedal and it was solid when you stood on it.

I haven't replaced them, but they all look ok. Definitely something I should probably do to rule it out.

If I had known I would need a brake booster I would have seriously considered going to hydroboost. I knew I needed a MC and the PS pump wasn't so hot. I did look but that shit is expensive and it put me off. Money has gotten a bit tighter as business has slowed. I was hoping to be spending on my drivers seat foam and leather at this point. That might have to wait until next year now as I've pretty much depleted my yearly truck budget.

 

[OR VietVet]

Those flex hoses can look great on the outside but be a ************* on the inside.

Plus the brake fluid temp can make the difference as to why is ok one minute and not ok the next.

 

[96-2D-Hoe]

AFAIK there's only two short pieces at the front calipers. About 18" each. IIRC the rear is all hard line. Unless there's a hose in the middle of the truck somewhere?

 

[east302]

There’s the soft line at the rear axle.

I’d still run the shoes out a smidge.

 

[96-2D-Hoe]

I just got under it and looked. I'd forgotten that I do have that short piece at the back. But all 3 hoses are solid with no signs of perishing whatsoever. Truck has always lived under cover or in a garage.

Shoes are adjusted, footbrake is right at the top.

I did have a slight issue the last time I tried to bleed it. I'd broken my previous glass jar and forgot to put a breather hole in the lid of the new one which didn't help. But I ran out of my 4th gallon of fluid and haven't bought any more. I also figured I'd probably have to remove the MC for the booster install and will be starting all over again in a few days so there was no point.

Pedal travel isn't too bad but it's not firm as it should be. I actually took video a few different times while pressing the brake pedal so I could see if I was getting anywhere. Travel improved every time.

It's all fun and games over here.

 

[BentleyArnage]

Greetings. The triple loop dissipates heat. Apparently it works. I won't trap air. Tap it a few times if it makes you feel better. Your pedal issue is because your rear drum brakes aren't adjusted correctly. You gave it away when you said you didn't get much from the rear. Happens all the time. With the amount of heavy hauling we do, it's essential our rears work perfectly. Get in there and adjust the shoes. You may want to find an old fashioned brake shop who can arc the shoes to the drum. Something not done these days. But at the very least, adjust them until they barely drag. I mean you hear them touch the drum a bit while turning. Don't rely on self adjusters. They don't. Adjust them at every oil change or more frequently if you're a hairball driver like me. Upgrade your fronts to drilled and slotted rotors and ceramic pads. Wilwoods if the truck is worth it to you. I hope this solves your problems.

 

[BentleyArnage]

Another thought. Are your calipers sliding on the pins? I've seen this before. Another one. When you stand on the brakes, does the idle speed change? (running, stationary) What are you using for brake pads?

 

[96-2D-Hoe]

Greetings. The triple loop dissipates heat. Apparently it works. I won't trap air. Tap it a few times if it makes you feel better. Your pedal issue is because your rear drum brakes aren't adjusted correctly. You gave it away when you said you didn't get much from the rear. Happens all the time. With the amount of heavy hauling we do, it's essential our rears work perfectly. Get in there and adjust the shoes. You may want to find an old fashioned brake shop who can arc the shoes to the drum. Something not done these days. But at the very least, adjust them until they barely drag. I mean you hear them touch the drum a bit while turning. Don't rely on self adjusters. They don't. Adjust them at every oil change or more frequently if you're a hairball driver like me. Upgrade your fronts to drilled and slotted rotors and ceramic pads. Wilwoods if the truck is worth it to you. I hope this solves your problems.

The rear brakes have just been replaced and are fully adjusted. I will replace front brake components at some point but the cheap pads and rotors only have a couple thousand miles on them. I also figured I would try to get everything else/the pedal right first as replacing front brakes won't change that much if at all.

I do need to service my front calipers though as the passenger is dragging, squeaking and annoying me.

FYI The initial post was while I had a bad MC that had locked itself up. I've been through a few more since then.

Thanks for the suggestions

 

[BentleyArnage]

The dragging caliper may be your issue. They have to float in order to get full application on the rotor. Some of the MC available are pure junk. Might be better to hone the bore and build it yourself. Just a thought.

Are the rears adjusted fairly tight? You have to have some contact shoe to drum. I would recommend you find one of those old brake supply houses. We have had tremendous success with going back to the old way of doing things. We did the brakes on a 62 Corvette a couple of years ago. Customer wouldn't drive it because it grabbed and had issues. We replaced the shoe material with the same friction all the way around, scuffed the drums, arced the shoes to the drum and installed. Three test drives and adjustments, the car would stop like discs. Hammer the pedal, let go of the wheel and you get a straight stop. Believe me when I tell you that drum brakes these days are not working as intended. Get new drums and shoes, drop the shoes in the drum and see the amount of friction touching the drum. Less than half. Arcing will get you 100% contact!

Good luck buddy. Been there, done that!

 

[96-2D-Hoe]

The brakes work fine but the pedal isn't great/as good as it should be. The footbrake is a very good indicator of how much the rear brakes need adjusting and mine is right at the top.
I've had a firmer pedal already during this saga than I have right now. I'm not going to give up, or settle, as I've done too much already for that. Will see how I get on after I replace the brake booster. I'll also probably check the MC with another bench bleed, but I'll put teflon tape on the plugs this time and see if it really is drawing in air or not.

If I still have my original MC (Can't remember if I used it for a core or not) I will use that reservoir with the AZ Duralast MC I still have and prep it in case I need to use it.

Thanks for everyone's support and advice.

 

[OR VietVet]

I used to change boosters by just unbolting the MC and with the soft flexible lines attached just pushed out of the way and removed booster and never cracked a line. If you have room and long enough lines you can do that.

 

[east302]

Did the same on my 98, just moved the MC forward to fit the booster and didn’t disconnect the lines.

For whatever reason, the brakes were fantastic after that. Probably some stray bubble that worked itself out while the MC was tipped and jostled.

 

[96-2D-Hoe]

I'll see how far I can maneuver it without creasing anything. Haynes manual doesn't mention removing it.

Booster should come tomorrow.

 

[iamdub]

I used to change boosters by just unbolting the MC and with the soft flexible lines attached just pushed out of the way and removed booster and never cracked a line. If you have room and long enough lines you can do that.

Yup. I did my hydraboost conversion like this.

 

[OR VietVet]

Yea, just want to make sure the master cylinder is sealed tight and try to move it and keep upright as you position it to wherever you move it to.