Bush mechanics.........Brakes and Wheelbearings
Submitted: Monday, Jan 28, 2008 at 14:03
ThreadID:
53967
Views:
2985
Replies:
18
FollowUps:
8
This Thread has been Archived
Willem
Now that I am mechanic-less (ref post 53896) I thought I had better try some things myself.
Rang me mate
John who lives by the river, and he suggested that I remove the brake calipers from their fixed position, tie them securely to somewhere on the front end, manufacture a wood spacer to fit inbetween the brake pads ,making sure it is all thoroughlyt tied and cannot shake loose and go for a drive to see if the hubs were still heating up.
Did just that with tie-wire and plastic cable ties and went for a 20km run, being careful not to touch the brakes and used gears and the handbrake only.
Hubs were cool when I got
home. Then I reassembled the lot and went for another 20km run and guess what, Hubs were HOT!
So there you go, it is a crook brake system all along and not the wheelbearings. What a monumental stuff up by the mechanic who does not have an enquiring mind and me for not being smart enough to look for other things. Anyway I got lots and lots of advice from the
forum.
Now I have to ascertain just what part of the brake system is playing up since the GQ has new Rotors and new Brake Pads.
Better go have a nap first though and wait for the cool of the late afternoon to come........................................lol
Cheers
Reply By: Footloose - Monday, Jan 28, 2008 at 15:14
Monday, Jan 28, 2008 at 15:14
Willem, on several occasions I've been given (and paid for) so called "expert" advice that was very wrong.
One mob even had me convinced that one side of the chassis was shorter than the other! I had to have a smash place do a laser analysis. There was nothing wrong with the chassis at all.
When I had the
suspension replaced, my expensive "4wd specialist" told me that there was nothing wrong with it ! Then he had the gall to tell me "now it drives like a completely different vehicle."
My advice is to trust your instincts after considering the
forum advice. You are the person who knows the vehicle best.
AnswerID:
284101
Reply By: Wayne (NSW) - Monday, Jan 28, 2008 at 16:26
Monday, Jan 28, 2008 at 16:26
Willem,
Just thinking out loud and this could be a bit over the place.
Both front brakes are getting hot. That could mean that the hydraulic oil is not returning to the master cylinder and holding the brake pads on.
The oil could be old and retaining water.
There could be air in the lines.
The brake lines could be kinked or partly blocked and not allowing the oil to return.
If the bleed nipple is lose, as if you were going to bleed the system some oil should start to drip out of the nipple with out depressing the brake pedal.
The oil should be the same colour as the new oil that is going into the master cylinder.
Bleeding the brakes would be the first thing that I would do. The "mechanic" might have said that this was done but I would do it again.
In the callipers there are pins/bolts that allow the calliper to move.
Remove the calipers from the vehicle. Vice grips can be used to clamp off the brake line while this taking place. Do one side at a time.
Once the brake pads are removed the piston should be able to be pushed in and out. If this is tight the pins could be rusted, bent or just lacking grease.
Wayne
AnswerID:
284112
Follow Up By: Member - joc45 (WA) - Monday, Jan 28, 2008 at 18:32
Monday, Jan 28, 2008 at 18:32
Just for the hell of it,
check the free-play between the actuating rod on the pedal and the master cyl piston. If zero, you might have a problem there.
The book specifies pedal travel has to be 1-3mm before actuating the piston.
Gerry
FollowupID:
548895
Follow Up By: Wayne (NSW) - Monday, Jan 28, 2008 at 18:39
Monday, Jan 28, 2008 at 18:39
Willem,
While you are down there
check the return spring on the brake pedal and make sure that the pedal is returning.
With the ignition on
check and see if the brake lights are on all the time. This could also indicate if the brake pedal is not returning.
Wayne
FollowupID:
548897
Follow Up By: G.T. - Tuesday, Jan 29, 2008 at 13:50
Tuesday, Jan 29, 2008 at 13:50
Willem, don`t clamp your brake hose with a vise grip or similar. You may weaken the hose this way. Regards G.T.
FollowupID:
549065
Follow Up By: Member - Luke (SA) - Tuesday, Jan 29, 2008 at 21:17
Tuesday, Jan 29, 2008 at 21:17
G.T.
Why is it then you can buy brake line clamps??? The hose is only of a rubber type material so I personally don't think it would weaken it as it will spring back to it's normal shape IMO
Cheers Luke
FollowupID:
549141
Reply By: 96 GXL 80 series - Monday, Jan 28, 2008 at 19:14
Monday, Jan 28, 2008 at 19:14
Willem,
all along since you posted that you had changed Rotors I thought that you would have a problem with the pistons in the callipers.
You will have to pull apart and service the callipers.
For this you will have to get the kit with new "O" rings and piston seals and rubber boots, not forgetting the tool to push the pistons back into the calliper.
Once apart you will need some very fine emery paper to clan any rust or ridges off the sides op the piston and inside the calliper, as this is what will be the cause not letting the piston release it self from the Disc Rotor.
That $200.00 was probably a gift from the mechanic to cover your costs for this.
AnswerID:
284172
Follow Up By: 96 GXL 80 series - Monday, Jan 28, 2008 at 19:17
Monday, Jan 28, 2008 at 19:17
Also make sure there is nothing obstructing to guide pins on the callipers.
Make sure they move freely.
FollowupID:
548910
Reply By: Member - 'Lucy' - Tuesday, Jan 29, 2008 at 00:26
Tuesday, Jan 29, 2008 at 00:26
Evening Old Son.
I have been watching this saga and will now elucidate an experience I had with my 81 Datsun Bluebird that I have since new.
Approx 2-3 three years ago for no obvious reason whatsoever the front hubs ran hot and were giving off loads of that hot brake smell.
One evening it actually became harder to accelerate and there was a minor amount of noise issuing from the front wheels - both very hot.
So! down to the brake specialist I have used for years and he can't find anything at all, and the pads had heaps of 'meat' on them.
Short time later it happens again however this time I can't turn the wheel by hand, if jacked free of the ground.
Ring up the brake dude again - bring it in and I will have a look at it - So I do. Drove it about 16 Kms and arrive with smoke emanating from the front Brake calipers.
I also took along a spare master cylinder I had acquired years before hand for 'just in case'.
It turned out to be the Master Cylinder alright and rather than stuff around trying to find out what exactly was wrong with it I just had him put my new replacement one on.
Never missed a beat since.
In your case if that is the cause, fine, however I would respectfully suggest that you get the caliper pistons serviced as
well.
AnswerID:
284257