Team Camaro Tech banner
1 - 20 of 60 Posts

·
Premium Member
Joined
·
22,122 Posts
Discussion Starter · #1 · (Edited)
I spent the last 2 days bleeding my new wilwood 4 wheel disk brakes. I used a mity-vac, some tubing, and an empty brake fluid jug. I've emptied (NO not really empty, ya know, just 2 refills!) the master twice with no bubbles coming out each of the 8 bleeders.

I have a firm solid pedal... but it's just a couple inches off the floor!

Master is a wilwood 7/8". This is a manual system.

I'm wondering about the master cylinder pushrod adjustment, thinking maybe it's too short? The threaded end looked just like the stocker, and threaded right into the stock clevis. Even used the original jam nut.

The rod is part of this master. It would wiggle around, but not come out. I can't see any way to determine how much clearance there is. It was a real beetch getting it in there, too. Ended up having to pop the rubber boot off the end of the master, and rely on the friction of the boot against the shaft to screw it into the clevis. I screwed it in about halfway.
 

·
Premium Member
Joined
·
22,122 Posts
Discussion Starter · #2 ·
Re: master cylinder rod adjustment?

ok, measured ... The bend in the pedal is 3/4" from the collar around the base of the column when it stops. That's just plain too close. I haven't tried really mashing it to see if I can get it on the floor, just don't want to know.

And there's only a 1/4" of the rod sticking thru the clevis, that's not enough to make a difference.

WTF, gotta be something wrong, but what?
 

·
Premium Member
Joined
·
991 Posts
i just went through a 4 wheel disc manual brake install and had soft pedal issues after m/c bench bleeding (x3) and system bleeding and bleeding and bleeding.

I determined the soft pedal was caused by the front calipers by plugging the front port on the master. after plugging the front off, i had tall firm pedal.

I inspected the front clipers and noticed a decent sized gap between the inner pads and disc.
the fronts are 13" and dual piston (rather large) with a 1 inch dia deep bore M/C.

i then removed the front calipers, placed a (smaller than disc thickness) wrench between the pads and pressed pedal till tight. Allowed time to elapse and compressed the pads back to fit disc. pedal and brakes now normal.

Inspect gaps between inner pads and disc, if excessive the pedal will have more travel. Minimize the gap and pedal will rise.

hope this helps, i went through fits trying to figure my install disc problems.

joe c
 

·
Premium Member
Joined
·
22,122 Posts
Discussion Starter · #4 ·
interesting... I went around with a .0015" feeler guage, all the pads are right on the disks. Then I started sticking it between the pad and the pistons.

Note: these are 4 piston fixed calipers.

In front, I can pretty easily slide a .005" feeler guage between the lower pistons and the pads, both on both sides, all 4. Upper pistons are tight to the pads.
In back, drivers side both inboard pistons are not tight to the pads, and pass side, it's the put board pistons, I can get a .024" feeler guage in there!!

So I mashed the pedal hard a bunch of times and recheck. most of the pistons went out, but push back in pretty easy. The pedal is really spungy now. Guess I'm not done bleeding. Any tricks for dislodging the air trapped around the pistons?
 

·
Registered
Joined
·
13,315 Posts
Try the old "bleed open, pedel down and hold, close bleed method"
To measure the rod is a hassle...went thru it yrs ago when changing to a HQ holden MC...
used a vernier with rod out (rod was too long) shortened almost to therical length reassembled, disassembled shortened couple more times before getting right.
If u think the rod is too short, make up a dumbie rod longer and try, then work backwards as above

If the bleeds are at the top, trapped air should not be a problem..

And the suggestion above as to clamping off to find if front or back or even 1 side is also the way to go...
 

·
Registered
Joined
·
1,133 Posts
Jim
1. If the rotors are not tight as if the wheel was on they will have that. Put all lug nuts on backwards and lightly snug them. then feel your pedal.

2. Often new pads and disks need to have a few miles put on them to feel good.

3. Try gravity bleeding, leave the master open and all bleaders open, leave for a good t.v. show and check the master to see if some has moved.
Then close everthing up ( fill master) and try holding the pedal down lightly and open the lines to the master and porprtioning valve (one at a time and pump the pedal a couple of time in between)
Thats a hot spot for air to trap. (up high in the lines)

4. You cant compress a liquid, only the air mixed in with it. So if the mechanical linkage is tight, the rotors cant move as you step on the pedal, and you bleed the snots out of it with no ocasional bubbles then its time for a subdivision test drive. That will set things ( rotor pad sufaces) Your pedal may get better with a carefull miles.
 

·
Registered
Joined
·
10,515 Posts
Jim -

I know you're a big fan of gravity bleeding....

But this thing flat out works awesome. Hook it up and go around the car in the prescribed order. Hook your clear hose up and crack the bleeder. Lightly tap each caliper with a small hammer while bleeding. If there is any trapped air, you'll see it come out.

http://cgi.ebay.com/ebaymotors/Pres...625QQitemZ120097587186QQrdZ1QQsspagenameZWDVW

Also - at least on my factory disc/drum set-up, last summer I replaced the booster with a newer shinier one, and replaced the MC at the same time. When I was done bleeding, I had a solid pedal, but it was way too low. I disconnected the clevis from the pedal and unthreaded it to effectively lengthen the rod. The difference was amazing - had perfect pedal height.
 

·
Premium Member
Joined
·
22,122 Posts
Discussion Starter · #8 ·
I gave up on gravity and went with vacaum... Some how the thought of a half gallon of pressurized brake fluid at the top of my engine compartment sounds like a pending disaster of biblical proportions. If it comes to pressure, it will be towed to a shop for the job, and I will triple check thier liability insurance before they touch it.

I'm starting to get a lil discouraged here though. Last night, the joint in my 2 peice front to rear line gave a bit of a swuirt. The back half is new stainless, the front half old steel, I had to shorten the old steel and reflare, and that is where it leaked.

So I called right stuff and ordered the front half of thier 2 peice SS line to match the rear half...

Today after work I crawl under to finish off the exhaust hangers and notice fresh fluid dripping from where the rear hardline connects to the rubber (new SS hardline, factory flare, older rubber that didn't leak before) and also where BOTH axle hardlines go into the splitter! These are my single flares on new SS line. All three places leaked before, and I've toghtened the crap out of them.

So I guess tonight I'm gonna drain the rear half of the system, and buy new axle lines (at least I know how long they need to be now) and a new rubber line...

3rd week of march, and I'm getting ina hurry...
 

·
Registered
Joined
·
1,821 Posts
JimM,
I had problems in the back at the hardline/rubber/axle connections when I did mine some time ago. Everything was new with mine, but I really had to crank on it. I used another wrench to "back it up". You're using line wrenchs right? It's the only way to really get these things tight.
I used a little brake or carb cleaner to clean the connections after I got them tight so I could check them later with a rag.
It was such a pain to get the system bled when I did my rears.
Do you have an adjustable prop. valve in yet? If so, make sure it's all the way open while trying to bleed the rears.
 

·
Registered
Joined
·
13,315 Posts
As BPOS said, there's nothing as good as pressure bleeding. Gravity and vacuum work somewhat, but pressure works the best at getting all the air out.
I agree, I tried vac, but had problems...
 

·
Registered
Joined
·
519 Posts
Have to get all the leaks fixed before you can be sure you are bleeding air free.

A few months back I bled my system and every single brake component was new, from the brake pedal to the rotors. Some of the flared connections I had to wrench on so tight I thought for sure the line wrench was going to strip or the connection break. Also had two bad M/C (one obvious on the bench, one a desperate measure to get the system to bleed). When you change so much it can be a real pain to isolate the problem.
 

·
Premium Member
Joined
·
22,122 Posts
Discussion Starter · #13 ·
ya... yesterday I cleaned the grinding residue out of the interior and watched American Idol (Was Haley HOT HOT HOT or what? hehe, my wife is getting jealous, particularly when I drool...). Today I finished the tailpipe hangers and hooked up the ebrake cables, undercar done now. Currently working on installing carpeting. Wil also be checking stereo, have some blown speakers and need a new small subwoofer box.

Having a moratorium from brakes!
Another new line from right stuff will be here tomorrow.

Bummer of it is, car is real close to roadworthy again... and it would be ragtop weather if it stops raining.
 

·
Super Moderator
Joined
·
33,294 Posts
This is the problem with SS lines, harder material than standard steel to seal. You might get help sealing by installing a copper washer between the flare and the line, just like the banjo fitting on the caliper, copper washer on top and bottom. Same principle applies.

The pedal rod will be adjusted correctly when viewing the top of the open reservior, have an assistant press very slowly on the pedal and watch for a swirl of fluid in the reservior after the pedal is depressed. This indicates the piston is moving directly with the pedal. Fluid will swirl until the piston covers up the hole. There should be 1/8 inch freeplay in pedal to master cylinder.

Pistons must be against the pads and pads against the rotor. With pedal depressed hard and held, tap caliper with a small hammer to "loosen" the air bubbles in the chamber. Then bleed and perform again.

Tubing leaks must be fixed as you well know before proceeding or when found.

Good luck.
 

·
Premium Member
Joined
·
22,122 Posts
Discussion Starter · #15 ·
the new carpet looks real nice. Still need to get the pass side under the kick panel and put the sill plate on, and clean and install the console. The I'll tackle those speakers.

Yes, I know I'm in denial, but it works for me. After a few days of easy stuff, I'll tackle it again fresh, and all will be well. The easy stuff has to get done too.
 

·
Registered
Joined
·
1,133 Posts
Good attitude Jim you will get it after this break your taking, It will be almost a week till we can drive anywhy with all the rain. 3 inches last nite, I bet your pool is full now. Im going to orlando next week when I get back I will give you a call. If you still need help I can stop by if for nothing else moral support. I will even bring the beer. Beer helps these problems
 

·
Premium Member
Joined
·
22,122 Posts
Discussion Starter · #18 ·
Well, came home from work and got to it tonight. Opened up and "talked to" 3 leaking connections. Replaced the front part os the 2 peice front to rear line. That one was no fun, was a clamp right under the clutch z-bar!

but it's all together again, and I filled the master...

Waish me luck?
 

·
Premium Member
Joined
·
4,817 Posts
Good luck, Jim!
 

·
Premium Member
Joined
·
4,060 Posts
I had same problem when I changed my lines and drum to disc changeover.
I found out the master sits at an angle and the front brake section of the master has trapped air.
I called tech support for the new brake system and they recommended using a power bleeder.
http://www.apexperformance.net/cartgenie/prodInfo.asp?pid=47&cid=8
And would ya figure I bled with the power bleeder and everything works great!
much easier than the mighty vac way of bleeding.
 
1 - 20 of 60 Posts
Top