Brake dragging on passenger side,advice/help needed

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scampy

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This is on my 72 scamp manual brake/stock 73up disc conversion that has been on the car for a while,drag car and working fine.Had got a bit of pull in the pits so checked it out when we got home and found that the passenger side spinning the wheel didn't really spin,could move it put would stop when I let go,driver side was better tire would spin apprx a 1/4 rev after letting go.Cleaned and lubed slides re-assy and was a bit better,took it out and rechecked and was back like it was.So got a few weeks before the next race so i got new calipers and hoses and installed today figures i'd be good to go.After bleeding I can turn the drivers side with some effort but the pass is worse now then before.With the wheel off can barley move it with 2 hans on the studs,drivers side is a one hand deal.Do I have a bad new/rebuilt caliper,is it something with the bleeding?? If i crack the bleeder what should I get.When I took apart the pass side the brake fluid kept dripping out till I got the new hose in,had to keep the m/c filled up till I got it,the drivers side barley leaked at all and of course that hose went right in.Have good pedal but have not driven it at all yet.
Well that was long winded,just a bit baffled as the one side is holding and the other seems ok.

Thanks
 
Always better to change one part at a time. I would have changed hoses first and left the calipers to see what I had, the hoses are usually the culprit. Now you have to rule out the new calipers and the hoses again.

New hoses can be bad, so can calipers, although it would be a pretty big coincidence either way to have it be the same side as before.

What did the fluid coming from the passenger side look like? The lines should drain fluid the whole time when they’re unhooked.

Have you checked the wheel with the calipers off to confirm its brake related?Could be wheel bearings if you haven’t.

I would inspect all the hard lines back to the master cylinder, a little crimp in the line can cause problem. So can crud, so if the brake fluid isn’t coming out clear it may be time to flush it out.
 
The only thing that pulls the caliper pads off the rotor is the piston seals. Not sure what's going on. Are your bearings good, ie. turn fine with no caliper?
 
yes rotor spins fine without caliper.Fluid was pretty clear in the hose when bleeding,and the side that is dragging is the side that fluid ran the whole time it was apart,had to fill the master while playing with getting it back together before it ran dry. Its weird its worse now then before.
Thanks
 
wonder if you rolled a seal lip on a piston? Maybe pull the caliper and hose and see what piston cant be pushed back in manually, push that out and examine the seal.
 
If you just bought the calipers I wouldn't tear into it yet. Put your old caliper back on and see if anything changes. If nothing changes you've eliminated the caliper, unless both calipers happen to be bad. But even then you could exchange the one you just bought for another one if you don't tear it apart.
 
Very first thing is determine is it hydraulic or "other?" With it "sticking" that is displaying the symptom, wrench open the bleeder/ line fitting just a second or two to relieve any pressure and see if it improves.

There are a fair number of other problems, including bent mounting, sticking piston, bad seal as Pishta pointed out.
 
67Dart273 said:
Very first thing is determine is it hydraulic or "other?" With it "sticking" that is displaying the symptom, wrench open the bleeder/ line fitting just a second or two to relieve any pressure and see if it improves.

There are a fair number of other problems, including bent mounting, sticking piston, bad seal as Pishta pointed out.
Click to expand...

ok thats what I was thinking,if I crack the bleeder and it stays the same we are looking at caliper?? or other???. If it gets better then looking at hose or ???.
THese are the single piston slider calipers and I just bought them rebuilt from advance auto
 
pishta said:
wonder if you rolled a seal lip on a piston? Maybe pull the caliper and hose and see what piston cant be pushed back in manually, push that out and examine the seal.
Click to expand...

This is a single piston slider caliper that i bought rebuilt at auto store,never been inside there and probably wouldn't know what i was looking for
 
single piston slider make sure you got the astroglide on the pins. The lip seal is just a (almost) square cut O-ring around the piston inside the piston bore. Im not sure there is a trick on installing these but it may just pop out and slide back in. Check back before you pop it, maybe someone will chime in and tell you the secret of installing caliper piston seals.
 
Here is a hack video. The seal is installed in the bore then the piston is pushed in. Makes sense.
 
scampy said:
This is a single piston slider caliper that i bought rebuilt at auto store,never been inside there and probably wouldn't know what i was looking for
Click to expand...

"rebuilt" Right there you have suspicions. Could be a rough bore or rough piston.
 
You guys remember that he had the same problem with his original caliper right? That’s why he replaced it.

Seems like a pretty big coincidence that he would have the same problem with two different calipers and the calipers are the source. I mean, he installed two rebuilt calipers, the other side still works fine. So not only did he get a bad rebuilt caliper that had the same problem as his original, but it’s on the same side too?

But what the heck, tear down the rebuilt caliper instead of returning it for another one. Sure. Couldn’t possibly be a problem somewhere else.
 
ok so I cracked the bleeder a little fluid came out but no geyser,just kinda run out and didn't feel any different.What does seem to make it better is loosening the hold down hardware bolts not sure if that tells me something.I was using 180in pounds as a torque for those.I also took the pads out and installed the caliper and it was hard to push back and forth on the slides with the hold downs on so I put my brake grease on the areas where the hardware goes and it did improve without the pads in as far as moving the caliper.Went over the slide areas again this time with a flat file regreased/assy etc push pedal to bring piston out and same deal can barley turn rotor.Now even before i go to bring the piston back out it gets tighter as i tighten down the hardware trying to turn the rotor and then when i hit the pedal and come back to check its very hard to turn.Do these adapters go bad,bad casting on the caliper?? I assume not hydraulic as cracking the bleeder didn't really change anything.Only other thing I notice is with the pads off this "new" caliper when pulled to the outside on the slides can come off the top slide where the "old" caliper does not,can't see what stops this,it does not appear to be the piston,probably means nothing but it was an observation.
Any thoughts would be helpful
 
Well, the fact that there isn't a pressure release from cracking the bleeder and that the rotor doesn't turn freely after you've cracked the bleeder (and done nothing else) would suggest that it isn't a hydraulic problem. If the hydraulic system was holding pressure and keeping the brakes applied cracking the bleeder should release the pressure and temporarily fix the problem until the brakes are applied again.

That would tend to indicate a mechanical problem with the piston or the caliper not returning. Are there any obvious differences that you see between the driver and passenger side? I assume you used the same install procedure on both sides, and the driver's side is working properly yes?
 
Yes same deal.when i go to reinstall,push the piston back with one of those twist knob tools install pads and caliper it spins pretty free but as I tighten the holding hardware down it does get harder to spin,is this kinda normal?? Then when i push the brake petal bake up and recheck it is very hard to turn. I did loosen the harware on the driver side and it did not seem to change the amount of effort to spin but I didn't remove anything and start from scratch on that side today
 
show us a pic of the caliper to the bracket. Sounds like the mounting ears are not even and possible distorting the caliper when you are torquing them down. The ears should sit flat on the bracket with no bolts in them. The castings are probably not repopped but bead blasted, and the piston and lip seal are replaced so as to call them 'remanufactured'.
 
Here are some pics of what I think you are asking

IMG_20200817_171907444.jpg


IMG_20200817_171808090.jpg


IMG_20200817_171912676.jpg
 
ok some more looking/replacing today.Replaced the caliper to have it do the same thing,not surprising but was hoping,lol. What I did find though is the passenger side caliper will rock when applying the brake and if I can move it back it frees up so I'm thinking my adapter/mount is worn out. The drivers side does not do this. So does that sound like the mount being worn or should I be looking elsewhere???
 
Personally at this point I'd replace BOTH. It might be one is braking harder than it should and the other sticking. IS IT POSSIBLE they are different bore size? I forget "what that is" Volare? That is, there is a later application calipers you can use, larger bores, will give harder braking, but of course you must have BOTH of one size or the other (Measure the pistons)
 
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