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Old 10-31-2012, 11:39 AM   #1
ubtripn
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Here is a test of knowledge

So I have been having trouble installing new front brakes and hardware on my 68, Secret Squirrell pointed me to the retainer springs. (Thanks for that) They were indeed sticking out farther than the side of the shoe. I look at the hardware rebuild kit and it has 8 pins that these retainer rings latch on to. 4 are shorter than the other 4. I put the short ones on and gain the clearance I need.

What are the longer one's for? Did our trucks come with more than one style of drum brakes in the same year?

Also, can anybody tell me if the front brakes are on the same "circuit" or is it corner to corner. I cannot get the front brakes to bleed right. I know that the procedure starts in the rear but in the past on other vehicles I have been able to just bleed the front. I had to put new wheel cylinders on both front drums so I know I got a lot of air, thanks for the help.
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Old 10-31-2012, 11:44 AM   #2
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Re: Here is a test of knowledge

The extra pins are for different applications. That way one kit can fit a larger variety of vehicles, subsequently, less parts to keep stocked on the shelf.

The front brakes are indeed on the same circuit. There is a tee on the crossmember where they split off to go to each side.
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Old 10-31-2012, 11:46 AM   #3
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Re: Here is a test of knowledge

Thanks TX Firefighter (You helped me complete my ball joint job as well).

Man those extra pins really threw me, Murphy's law that I would somehow grab the longer ones.

I bled and bled both front brakes but still getting a brake light with the pedal going to the floor. I have power assist as well but I don't think that matters. The only thing I can do is to keep bleeding them right?
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Old 10-31-2012, 12:40 PM   #4
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Re: Here is a test of knowledge

Quote:
Originally Posted by ubtripn View Post
I bled and bled both front brakes but still getting a brake light with the pedal going to the floor.... The only thing I can do is to keep bleeding them right?
Are you still getting air out of the front lines? If not, your problem is likely the rear brakes. Didn't you have a rear wheel cylinder that you couldn't get to bleed at all? Or is that fixed now?
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Old 10-31-2012, 12:47 PM   #5
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Re: Here is a test of knowledge

Not getting any air out of the front lines and I have not had time to move to working the rear brakes yet where there is one not bleeding at all but..if they are on separate circuits how can this affect the front brakes? Also, is there a procedure I need to perform on my master cylinder ie a something I need to lossen and let the bubbles rise? (I have read about something like that on here.)

Before I started this job I had good pressure on the brake pedal even though it appears the passenger rear is not functioning.
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Old 10-31-2012, 01:01 PM   #6
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Re: Here is a test of knowledge

I forgot if you replaced the master cylinder.... if so, it has to be bench bled (you can actually do this after it's mounted) before bleeding the lines.

Yes, the rears are on a separate circuit so they won't affect the fronts. But a problem with the rears can allow the pedal to go to the floor. Figure out why that rear cylinder won't bleed. Could be the bleeder valve is just plugged. That's a common problem and easily fixed -- just remove the bleeder and pick the mud out of it. Maybe the rear wheel cylinders need to be replaced?
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Old 10-31-2012, 01:04 PM   #7
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Re: Here is a test of knowledge

I will do that, thanks. (I didn't replace the MC just the wheel cylinders in the front.)
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Old 11-03-2012, 03:21 AM   #8
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Re: Here is a test of knowledge

Got here late, but here goes with my bit o' knowledge.

First off- a wheel cylinder that won't bleed is a cause for more inquiry. Replacing both sides is highly recommended and cheap (compared to the cost of using someone's car to stop with).

Next- don't push the pedal to the floor- especially an old master cylinder. The accumulated nastiness in the extremes of the MC bores will damage the seals on the pistons. Then, instant internal leak, and no pedal pressure- no matter how much you pump it. My uncle (who had me working in his shop when I was a young whippersnapper- my 'little hands' could get in tight spots) showed me that putting your other foot (quick, easy way) or a hunk of wood (means forethought and preparededness) to prevent the tragic inadvertent murder of the master cylinder. Haven't ruined one yet.

Most older systems tend to have a lot of internal damage, leaking wheel cylinders only accelerate the deterioration. Brake componentry is pretty cheap these days, and replacing any 'vintage' item is prudent and in the long run, economical.

Not the worst thing that can happen, but not the best either. Flushing the fluid every year (for a weekend warrior) or every two years (your daily driver) avoids a whole lotta headaches and unpleasant surprises.

Hope this helps, and your project goes well. I've got a real nightmare with my '70 C10, the brakes are the least of the problems.
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Old 11-03-2012, 10:59 AM   #9
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Re: Here is a test of knowledge

Thanks Mototrcrtitter, I had no idea about the pedal to the floor issue. Yeah, this brake job has taken many hours from me and much more money. Disk brakes would have been 20 minutes. It sucks but I should be on the road today.
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Old 11-03-2012, 11:32 AM   #10
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Re: Here is a test of knowledge

Glad to be of service. As I used to tell my customers- -It's my job to fix it, it's your job to break it! Please don't upset that delicate balance of forces of the universe!'

Not letting the MC bottom out (even with the new one) will avoid creating a problem- which is exactly the best way to solve a problem.

Drum brakes are a lot more 'fussy' than discs, but disc brakes have their own set of unique problems. I don't think there's too many 'set and forget' items on a vehicle. Well, maybe a seat adjustment.

If time really was money, I'd have retired a looong time ago! And quite well off, at that!
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