The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-28-2010, 11:29 AM   #1
airbrushguy
Registered User
 
Join Date: May 2010
Location: hawthorne, nj
Posts: 217
brake light????

rear brake line broke on my '71 C10...replaced steel and rubber lines and one wheel cylinder. Checked all else, emergency brake as well. Light is still on, brakes work fine and no leaks.
Any ideas?
airbrushguy is offline   Reply With Quote
Old 06-28-2010, 12:17 PM   #2
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: brake light????

did you bleed brakes with pin clamped in on the proportioning valve like the service manual directs for proper bleeding?
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 06-28-2010, 02:33 PM   #3
airbrushguy
Registered User
 
Join Date: May 2010
Location: hawthorne, nj
Posts: 217
Re: brake light????

No...don't have a shop manual. Probably have bled over 500 cars in my life since my father had a station while I was growing up, never clamped the pin on the prop. valve. Do you really think that is the problem? If so, how should it be done?

Last edited by airbrushguy; 06-28-2010 at 03:52 PM.
airbrushguy is offline   Reply With Quote
Old 06-28-2010, 04:38 PM   #4
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: brake light????

clamping the pin when bleeding is considered by the factory to b the proper way i think thats why they put instructions in the service manual to instruct mechanics how to do the job properly the first time
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 06-28-2010, 05:00 PM   #5
Notrodder
Registered User
 
Join Date: Jun 2010
Location: Lompoc, CA
Posts: 104
Re: brake light????

Brake light switch may need adjustment or it got cocked in the whole while you were working in there. Have a look at it.

I would suggest you do your brakes in pairs, if not all at once. Replacing just one wheel cylinder almost guarantees you will be doing the same work on the other side soon.

A good Chilton or Clymer manual is well worth the purchase price. Haynes, not so much.
Notrodder is offline   Reply With Quote
Old 06-28-2010, 05:07 PM   #6
grs
Registered User
 
Join Date: Jan 2010
Location: Roanoke, Tx.
Posts: 1,561
Re: brake light????

I never heard of a pin on the proportioning valve. Do you have a picture of it.
grs is offline   Reply With Quote
Old 06-28-2010, 05:40 PM   #7
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: brake light????

its sorta toward the front sometimes covered by rubber bulb like the pumper on small engines that you prime the carb with
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 06-29-2010, 01:48 PM   #8
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
Re: brake light????

There is no adjustement on this switch... we are talking the brake warning lamp, not the rear lights.
If you have a good firm high pedal, then I would start by stomping on the brakes like you were doing 100 MPH and a cow jumped in front of you. This can reset the prop valve.
Longhorn Man is offline   Reply With Quote
Old 06-29-2010, 07:33 PM   #9
junkyardjohn
Registered User
 
junkyardjohn's Avatar
 
Join Date: Aug 2001
Location: SOMERSET KY.
Posts: 6,427
Re: brake light????

Quote:
Originally Posted by Longhorn Man View Post
There is no adjustement on this switch... we are talking the brake warning lamp, not the rear lights.
If you have a good firm high pedal, then I would start by stomping on the brakes like you were doing 100 MPH and a cow jumped in front of you. This can reset the prop valve.
IT'S ALWAYS WORKED FOR ME. THATS EXACTLY WHAT I'D RECOMMEND. THAT 100 MPH-COW ANOLOGY IS GREAT. HOPE YOU DON'T MIND IF I USE IT IN THE FUTURE. JOHN
__________________
junkyardjohn
69 1 TON TOW TRUCK //
84 4WD CUCV BLAZER// 85 1 TON 4WD STAKE TRUCK// 86 M1031 5/4 TON 4WD CUCV// ALOT OF OLD TRUCKS FOR ONE OLD MAN TO DRIVE. THERES ROOM FOR ALL OF GODS CREATURES RIGHT NEXT TO MY MASHED POTATOES//
LIFE MEMBER OF P.E.T.A (PEOPLE EATING TASTY ANIMALS)

DON'T RENT U-HAUL

ALWAYS TELL THE TRUTH
IT WILL AMAZE PART OF THE PEOPLE & ASTONISH THE REST
junkyardjohn is offline   Reply With Quote
Old 06-29-2010, 08:14 PM   #10
LONGHAIR
just can't cover up my redneck
 
Join Date: May 2004
Location: Columbus OH
Posts: 11,414
Re: brake light????

BTW, the "Cow Stomp" is as much about speed than it is pressure. You have to "snap" it...pretty hard. It doesn't always work though...

If the "Cow stomp" doesn't work...
Open one of the front bleeder screws, have a helper push the pedal down to the floor, the will be a "click" that you can actually feel. Tighten the bleeder.
What happens is that there is a "pressure imbalance" and the proportioning valve is kicking into a "safety mode" that cuts-off the end with the low pressure.
__________________
You can review the site's rules here.



Quote:
Originally Posted by Longhorn Man View Post
As for reading directions...
The directions are nothing but another man's opinion.
Learn from the mistakes of others, you won't live long enough to make them all yourself...

Bad planning on your part does not necessarily constitute an instant emergency on my part....

The great thing about being a pessimist is that you are either pleasantly surprised or right.
LONGHAIR is offline   Reply With Quote
Old 06-30-2010, 12:12 AM   #11
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
Re: brake light????

Cow Stomp... I like that!
John... feel free to use it. I like making anologies that EVERYONE can get.
Longhorn Man is offline   Reply With Quote
Old 06-30-2010, 01:39 AM   #12
tim21391
Registered User
 
tim21391's Avatar
 
Join Date: Jul 2007
Location: Salina, Kansas
Posts: 1,998
Re: brake light????

i had my master cylinder go out on me last summer.. i installed that myself and the light was still on and i took it to sears automotive and they checked everything out and said some things in the rear needed a little adjusted since they were a hair off from being right
__________________
1972 C-10...402/400..flowmaster 40 series
1967 Mustang 347 stroker/C-4
1966 Mustang 289/3-speed
2013 Mustang V6/6speed w/300 ponies
I may be 23, but i sure do knows 67-72s are sexy!
Its not MPG its smiles per gallon!
build started 11/25/08
build thread: http://67-72chevytrucks.com/vboard/s....php?p=2993796
tim21391 is offline   Reply With Quote
Old 06-30-2010, 01:57 AM   #13
Notrodder
Registered User
 
Join Date: Jun 2010
Location: Lompoc, CA
Posts: 104
Re: brake light????

^Have you seen any cows in the road since then?

Last edited by Notrodder; 06-30-2010 at 01:58 AM.
Notrodder is offline   Reply With Quote
Old 07-04-2010, 11:13 PM   #14
airbrushguy
Registered User
 
Join Date: May 2010
Location: hawthorne, nj
Posts: 217
Re: brake light????

Tried the stomp...light still on. I only bought the truck two weeks ago, it sat a long time. I noticed today that the top of the MC keeps seeping fluid(just damp-looking), as if it's getting out from under the cover. Gasket looks good, area clean, dried/cleaned with brake cleaner...took out for ride and it's damp from top to halfway down again.
MC doesn't look too old. Could this be the prob? Going to check/bleed front wheel cylinders tomorrow.
Thanks

Last edited by airbrushguy; 07-05-2010 at 10:51 AM.
airbrushguy is offline   Reply With Quote
Old 07-05-2010, 01:07 PM   #15
airbrushguy
Registered User
 
Join Date: May 2010
Location: hawthorne, nj
Posts: 217
Re: brake light????

While waiting for Blaster to loosen front bleeders, I was tapping loose rust off a-frames...front right brake line broke right off hose when I tapped the ear that's welded to member. Guess I put new lines and hoses up front as well. Probably will replace calipers and pads and get it all new.
If the line was not leaking but that corroded it probably was not allowing fluid to go out and the pressure caused the MC to seep. Maybe, I'll see tomorrow after I get the parts from the parts store that's not open today.
airbrushguy is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 12:23 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com