Moparts
Front wheels don't turn !
Posted By: Wedgeman
Front wheels don't turn ! - 03/02/15 10:35 PM
I'm getting ready to start the new drag season beginning in May, and drop my ET's again...
I notice there is a lot of restriction coming from
the front rotors....
I jacked up the front of my car, and try to turn by hand the tires. With a good swing, they will barely make a full turn because there is a strong friction from the brake pads.
The car is also a dog to push in neutral...
Where is the problem ?
A bad MC that is not retracting the pistons ?
Bad calipers? (from '74 Dart new)
What are your ideas on the subject?
Dan
67 Barracuada
best 60 ft 1.30sec 6.40 1/8 mile
Posted By: Guitar Jones
Re: Front wheels don't turn ! - 03/02/15 10:41 PM
Just off the top of my head, calipers could be froze, flex lines might be restricted not allowing fluid back to the master cylinder or there may not be any free play in the brake pedal pushrod to the master cylinder leaving constant pressure on the brakes.
I would also check to see if any rubber parts that touch brake fluid are swollen. That would indicate contamination or the fluid.
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/02/15 10:45 PM
When I installed those disc brakes in the front,
I put brand new parts all around (calipers-lines-MC).....bleeded them beyond reasonable !
Dan
Posted By: Chassisman
Re: Front wheels don't turn ! - 03/02/15 10:49 PM
Quote:
When I installed those disc brakes in the front,
I put brand new parts all around (calipers-lines-MC).....bleeded them beyond reasonable !
Dan
If your car was a brake drum front car you need the correct porportioning valve. Drum brake cars have more residual pressure to hold the shoes closer to the drum. Disc brake cars dont need as much. We use 10 psi on drum cars and 2 psi on disc cars. Look into that being the cause.
Posted By: CHAPPER
Re: Front wheels don't turn ! - 03/02/15 10:51 PM
Make sure the brake pedal pivot is well lubed and coming all the way up when released.
DAMHIK
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/02/15 10:53 PM
I really don't remember...........
By looking at it, can you tell if the prop valve is for drum or disc brakes ?
Dan
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/02/15 10:55 PM
I plan to istall rear disc brake using GM calipers, Cherokee rotors and Dakota Master cyl...
Should use the Dakota prop valve ?
Dan
Posted By: Cab_Burge
Re: Front wheels don't turn ! - 03/02/15 11:05 PM
Try loosening the bleeder vale and see if it has pressure or not
If it has pressure you may have a residual valve in the brake master cylinder keeping pressure on the front disc brakes, not really needed if the master cylinder is mounted above the calipers
If the master cylinder is mounted below the brake calipers you will need a 3 lb or so, not 10 lbs
residual valve to prevent the calipers draining back into and overfilling the master cylinders. Let us know what you find out
Posted By: dvw
Re: Front wheels don't turn ! - 03/02/15 11:48 PM
Quote:
I plan to istall rear disc brake using GM calipers, Cherokee rotors and Dakota Master cyl...
Should use the Dakota prop valve ?
Dan
No, buy an adjustable valve. I wouldn't worry to much about the brake drag, pretty normal. Make sure the pads move nice in the brackets, it'll be fine.They're cheap and then you can get it where you want it. If It's a drag only car with skinny fronts put it in the front brake line.
Doug
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/03/15 01:27 AM
Ok.........so get an adjust prop valve for the front....what about the rear ??? direct from the Dakota MC ?
Posted By: MR_P_BODY
Re: Front wheels don't turn ! - 03/03/15 01:34 AM
Quote:
Ok.........so get an adjust prop valve for the front....what about the rear ??? direct from the Dakota MC ?
Yep..... on your fronts.. loosen the bleeder and spin
the wheel.. if it turns freely then you have a issue..
I dont have any stop within a turn(disc brakes)...
also a little trick is run your front bearings a
little loose to get just a MINOR bit of wobble to
kick the pads back quicker
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/03/15 02:05 AM
I just tried loosening the bleeder screws and turn the tires.....the pads are still sticking to the rotor and making it hard to turn by hand.....
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/03/15 02:08 AM
Let me get this.....
If I put the prop valve for the front and direct from the master to the rear, there will be more braking from the rear than the front ??
Posted By: MR_P_BODY
Re: Front wheels don't turn ! - 03/03/15 02:31 AM
Quote:
Let me get this.....
If I put the prop valve for the front and direct from the master to the rear, there will be more braking from the rear than the front ??
You are correct.. if you run big tires on the rear
and skinnies up front the fronts dont have the braking
ability so you want more from the rears
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/03/15 02:42 AM
Ok thanks P !
But it doesn't solve my problem of front discs dragging..........
Posted By: MR_P_BODY
Re: Front wheels don't turn ! - 03/03/15 03:09 AM
Quote:
Ok thanks P !
But it doesn't solve my problem of front discs dragging..........
No it doesnt.. your pads are dragging for some reason..
either the pressure doesnt let them back or they
are rusty on the sliders... JMO
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/03/15 05:02 AM
After inspections, I let off the bleeders again and it seems like it is always pushing the piston in the caliper, like a constant small pressure...
The brale pedal has lots of freedom to retract...
Dan
Posted By: gtsdude
Re: Front wheels don't turn ! - 03/03/15 07:49 AM
do you have the correct length pushrod from the brake pedal to master cylinder? Also make sure the pedal is going back all the way, When I switched to manual brakes my pedal did not come all the way back and I had the same problem you do.
Posted By: OUTLAWSSAA
Re: Front wheels don't turn ! - 03/03/15 12:15 PM
If there Wilwoods join the club.
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/03/15 02:27 PM
Are there better quality callipers somewhere to prevent this ?
Or may be a bigger bore master cylinder ?
Dan
Posted By: littleVAL
Re: Front wheels don't turn ! - 03/03/15 04:11 PM
I forget what the hole is called in the master cylinder but if your pushrod is to long it will not let the pressure bleed back through the hole. So your brakes will just lock up harder (pump up) every time you push on them
Posted By: Crizila
Re: Front wheels don't turn ! - 03/03/15 04:30 PM
Quote:
I just tried loosening the bleeder screws and turn the tires.....the pads are still sticking to the rotor and making it hard to turn by hand.....
If you have the bleeder screws loose and the brakes are still dragging, the problem is in the calipers. Forget everything else for now ( not a hydraulic problem )and go directly to the calipers. Pistons are not retracting ( worn square cut "O" rings or corrosion in the piston bores / pistons. Other issue could be calipers not sliding on the pins or on the sliders - again, corrosion. 
Posted By: Crizila
Re: Front wheels don't turn ! - 03/03/15 04:33 PM
Quote:
I forget what the hole is called in the master cylinder but if your pushrod is to long it will not let the pressure bleed back through the hole. So your brakes will just lock up harder (pump up) every time you push on them
Compensating port. Not his problem if the brakes still drag after he opens the bleeder screws. I think he said he has pushrod clearance.
Posted By: 66coronet
Re: Front wheels don't turn ! - 03/03/15 04:39 PM
How long has the car been sitting? We have high humidity and this happens every winter to our cars. Drive it around and drag the brakes and see if the corrosion/surface rust grinds off and they free up.
Posted By: Crizila
Re: Front wheels don't turn ! - 03/03/15 04:46 PM
Quote:
How long has the car been sitting? We have high humidity and this happens every winter to our cars. Drive it around and drag the brakes and see if the corrosion/surface rust grinds off and they free up.
- is that like a hillbilly tune up? " hold the gas peddle on the floor and what ever is holding it back will break loose and blow out". 
Posted By: 66coronet
Re: Front wheels don't turn ! - 03/03/15 04:49 PM
Drag the brake to eat the surface rust off while driving through the pits. Not hold the brake. Big difference.
Posted By: Airwoofer
Re: Front wheels don't turn ! - 03/03/15 05:52 PM
I was noticing some surface rust on my disk rotors last weekend. Tis the season...
Posted By: pittsburghracer
Re: Front wheels don't turn ! - 03/03/15 06:16 PM
I think once again some of us are making a mountain out of a mole hole. The poster is from Canada and it is February. All disk brakes have some drag especially after that cold wheel bearing grease and Winter rust sets in.
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/03/15 07:51 PM
The car is in a heated garage, even in the summer it has that effect......
Like stated before I installed calipers and all other related components new....it's been doing that ever since but never corrected the problem
Again, like I said before the car is always a dog to push in the pits...
Dan
Posted By: Eric
Re: Front wheels don't turn ! - 03/03/15 08:03 PM
Do you have residual valves?
Posted By: camastomcat
Re: Front wheels don't turn ! - 03/03/15 09:04 PM
Did you convert from drum brakes? I remember from long ago that a drum brake master cyl. won't work on a disc set up?
Posted By: dragram440
Re: Front wheels don't turn ! - 03/03/15 10:00 PM
My car has done this same thing since I converted it to front disc. I used front disc setup off of a 80's diplomat. Spindles, rotors, calipers, and a master cyl from a 90's dodge ram truck I believe. The fronts just dont turn free when its jacked up. I dont think it is hurting my E.T.'s but I could be wrong.
Posted By: camastomcat
Re: Front wheels don't turn ! - 03/03/15 10:26 PM
Quote:
My car has done this same thing since I converted it to front disc. I used front disc setup off of a 80's diplomat. Spindles, rotors, calipers, and a master cyl from a 90's dodge ram truck I believe. The fronts just dont turn free when its jacked up. I dont think it is hurting my E.T.'s but I could be wrong.
If it's a front drum brake master, that may be the problem. And if there is enough resistance, and they grab or one does, think of the possibilities.
Posted By: cruzin
Re: Front wheels don't turn ! - 03/03/15 10:44 PM
Have you tried just removing the caliper completly and turning the rotor? If not, just pop it off and if you find the rotor difficult to spin, most likely you have overtighten the spindle nut and that's the source of the added drag.
If the rotor spins freely w/o the caliper you may try the attached tech tip which adds a spring to move the pads away from the rotor. Here's the link found in the archive.
http://www.moparts.org/Tech/Archive/brake/13.html
Posted By: dragram440
Re: Front wheels don't turn ! - 03/03/15 11:17 PM
Quote:
Quote:
My car has done this same thing since I converted it to front disc. I used front disc setup off of a 80's diplomat. Spindles, rotors, calipers, and a master cyl from a 90's dodge ram truck I believe. The fronts just dont turn free when its jacked up. I dont think it is hurting my E.T.'s but I could be wrong.
If it's a front drum brake master, that may be the problem. And if there is enough resistance, and they grab or one does, think of the possibilities.
It is a aluminum master off a 94 Ram with disc brakes. It is certainly drag from the pads. I hope no one has wheel bearings that tight or you are gonna have some major issues. I dont think you could get anything in the 90's with drum brakes! The master cyl. rod is correct length and not pushing the piston on the master.
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/04/15 12:30 AM
Yes it is converted from drum brakes...
I swapped to a disc brake MC, prop valve, and new parts all around, I left nothing on the table here....
Hoses bleed freely....non kinks...
Dan
Posted By: MR_P_BODY
Re: Front wheels don't turn ! - 03/04/15 01:13 AM
Quote:
Yes it is converted from drum brakes...
I swapped to a disc brake MC, prop valve, and new parts all around, I left nothing on the table here....
Hoses bleed freely....non kinks...
Dan
In this statement you say there seems like a small
pressure... IF I read it right
Quote:
After inspections, I let off the bleeders again and it seems like it is always pushing the piston in the caliper, like a constant small pressure...
The brale pedal has lots of freedom to retract...
Dan
Is that what your saying ... is there pressure there
or is it in the caliper (not rolling back)
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/04/15 03:46 AM
Yes even with the bleeder unscrewed, the piston still pushes on the rotor...making it hard to turn
Posted By: Sammy
Re: Front wheels don't turn ! - 03/04/15 03:57 AM
Pull the brake pads out and see if that's really the problem.
Posted By: Crizila
Re: Front wheels don't turn ! - 03/04/15 04:32 AM
Quote:
Yes even with the bleeder unscrewed, the piston still pushes on the rotor...making it hard to turn
Piston is not pushing on the rotor, it is just not retracting enough. Dirt, rust, misalignment, damaged pistons(chatter marks), etc. There should be some "slight" drag to keep foreign material from getting in between the rotors and pads. You should be able to spin the tire by hand and get at least 1.5 tire rotations out of it. Time to tear it down and find the problem - before this thread turns in to a real drag. 
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/04/15 05:42 AM
I hear you Crizila, sounds like the most logical explantion to me.....
I can't put much time on it during the week (work in day, baby after dinner, etc...)
I sure will keep you informed !
Thanks to all the replies and ideas !
Dan
Posted By: Crizila
Re: Front wheels don't turn ! - 03/04/15 07:30 AM
Quote:
I hear you Crizila, sounds like the most logical explantion to me.....
I can't put much time on it during the week (work in day, baby after dinner, etc...)
I sure will keep you informed !
Thanks to all the replies and ideas !
Dan
10-4 driver! Keep us tuned in.
Posted By: rickstershemi
Re: Front wheels don't turn ! - 03/05/15 02:02 AM
I've ran into situations where they are just tighter than I liked no matter what you did so I just turned the rotors to where they loosened up (not a street car)
Rickster
Posted By: rowin4
Re: Front wheels don't turn ! - 03/05/15 02:54 AM
I did the same swap years ago, mine don't spin freely either.I don't think it's to the point of loosing ET at the track though. On my 70 cuda with Wilwoods they spin like there's no pads in the calipers. I would like to hear from the mid 70 dart guys to hear how their stock disc brake units roll or don't. That would tell us if we have a problem.
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/05/15 04:16 AM
Quote:
I did the same swap years ago, mine don't spin freely either.I don't think it's to the point of loosing ET at the track though. On my 70 cuda with Wilwoods they spin like there's no pads in the calipers. I would like to hear from the mid 70 dart guys to hear how their stock disc brake units roll or don't. That would tell us if we have a problem.
A friends has a Barracuda just like yours and mine, his front runners turn freely, he had willwood brakes on it..............
Good to see I'm not alone !
Dan
Posted By: Crizila
Re: Front wheels don't turn ! - 03/06/15 01:15 AM
Quote:
I've ran into situations where they are just tighter than I liked no matter what you did so I just turned the rotors to where they loosened up (not a street car)
Rickster
On factory style disc brakes, the seal between the piston and the piston bore is a square cut "O" ring. Besides the obvious seal, the square cut "O" ring will deform slightly when you apply the brakes. Upon brake release, that "O" ring will pull the piston back slightly as it goes back to it's normal shape. If it has been in there for a long time, it doesn't do that so very good no mo - even though it doesn't leak. I have seen that "high drag " scenario go away with just a caliper rebuild with new "O" rings and boots.
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/06/15 01:20 AM
Since the calipers were bought new,Can you order a set of boot and o ring ? or you have to ship it for rebuild ?
Dan
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/06/15 01:22 AM
what if put a round O ring ?
Posted By: dvw
Re: Front wheels don't turn ! - 03/06/15 02:19 AM
Quote:
what if put a round O ring ?
The kits are about $10. I've taken rebuilds apart that were rusty and the piston stuck. As stated here Will Woods stick, I know mine do. It is reputed that the round O-rings for them are better. I'm going to try it and find out. My bet is even if they free up it won't make a difference in ET. But it's cheap so we'll see.
Doug
Posted By: Mopar-Al
Re: Front wheels don't turn ! - 03/07/15 05:17 AM
steel or ceramic piston cups in the calipers? Worked good at first when you first put it all together? With the bleeders open, can you apply pressure to the pedal and it comes out the bleeder?
My front wheels spin like the wheel of fortune, and stop the instant I apply preesure.Everything needs to be clean, lubed , and corrosion free,
Posted By: Wedgeman
Re: Front wheels don't turn ! - 03/07/15 05:21 AM
steel cup in the calipers.......
They are stock '74 set up.....
Dan