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Old 08-18-2021, 05:52 PM   #1
john68c10
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Front Brake Bleed Valves

I've noticed that over the years, as I've replaced wheel cylinders, the brake bleed valves for the front of the truck (68 C10) have gotten more and more difficult to get to with any wrench.

Is there a specific bleed valve that is correct ?

Are we just getting some sort of generic valve now that isn't quite right ?
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Old 08-19-2021, 12:07 AM   #2
lil hoodlum
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Re: Front Brake Bleed Valves

Most likely some rust or corrosion is building up in the bleeder valves. I too have had this issue on my 1968 C10 aftermarket disc brake set up. Every year it seems to get harder and harder to bust them bleeder valves open. Last year the one one the drivers side was full of crud that I had to clean out once I removed the bleeder valve.

Sorry, I don't have any advice on how to prevent it from happening and I have the little "rubber" caps on the bleeder valves as well.
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Old 08-19-2021, 07:56 AM   #3
jabborabbo
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Re: Front Brake Bleed Valves

Quote:
Originally Posted by john68c10 View Post
I've noticed that over the years, as I've replaced wheel cylinders, the brake bleed valves for the front of the truck (68 C10) have gotten more and more difficult to get to with any wrench.

Is there a specific bleed valve that is correct ?

Are we just getting some sort of generic valve now that isn't quite right ?
I just replaced the front wheel cylinders on my ‘67 GMC and noticed that…I compared them with the (probably original) ones I took off and didn’t notice any major change…I think I’m just getting old….
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Old 08-19-2021, 08:40 AM   #4
sick472
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Re: Front Brake Bleed Valves

I have notice this too. The older bleeder stems where longer than the replacements in some cases and I have found that the hex on the stem was 10mm on a recent set. It's about saving a penny and being made overseas.

There are many sizes of bleeder screws. You could try to replace the new short/small ones with longer ones. I'd bet a trip to Napa, along with the small bleeder screw would prove fruitful. Make sure the business end matches (size and threads) and the visible portion of the screw is longer.
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Old 08-19-2021, 08:41 AM   #5
john68c10
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Re: Front Brake Bleed Valves

No guys, I'm not really referring to old bleed valves being an issue, but brand new ones perhaps not being correct.

I can barely get a wrench on the front left, and the front right...I can only get a socket over...which makes the job messy since I can't use a hose.

This could also be an issue of a redesign from the original wheel cylinder. Does anyone have a really old front wheel cylinder to compare against ?

What I'm using is a new AC Delco wheel cylinder.
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Old 08-19-2021, 08:43 AM   #6
john68c10
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Re: Front Brake Bleed Valves

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Originally Posted by sick472 View Post
I have notice this too. The older bleeder stems where longer than the replacements in some cases and I have found that the hex on the stem was 10mm on a recent set. It's about saving a penny and being made overseas.

There are many sizes of bleeder screws. You could try to replace the new short/small ones with longer ones. I'd bet a trip to Napa, along with the small bleeder screw would prove fruitful. Make sure the business end matches (size and threads) and the visible portion of the screw is longer.
I think I'm going to try that this weekend...the trip to Napa...
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Old 08-19-2021, 09:25 AM   #7
sick472
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Re: Front Brake Bleed Valves

The newer shorter ones put the hex right at the wheel cylinder with the end nipple very close to the hex. The older longer ones would have the hex further from the wheel cylinder making it much easier to use a hose and have room for the wrench. Your looking for something like the first pic and NOT the second...
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1976 C10 (parts truck)
1985 K20
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Old 08-19-2021, 09:35 AM   #8
john68c10
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Re: Front Brake Bleed Valves

BTW if anyone needs to know...the thread size on these is 3/8-24
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