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werker Redwood Wrencher
Joined: March 08, 2004 Posts: 308 Location: Separating the drum from the axle...
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Posted: Tue Sep 20, 2011 10:47 am Post subject: Stuck Caliper? |
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Last night I was returning from the eastern Sierras to Davis Ca, and I had a problem that I can't figure out. Basically, the left front wheel started making noise (a periodic wump wump wump) that got worse until I pulled over for a second. If I continued, it would go away and then return randomly. This sound was also accompanied by a sort of thunk feeling.
After driving for a bit, the brake pedal dropped and I had about 20% braking power. I decided to pull off the road and AAA it home. While I was waiting for the tow truck I went to the left front wheel and it was waaay hot and smelled. By the time I got home and pulled the car off the flat bed, the brakes had returned and were feeling good again.
I was thinking that my soft lines were bad and not releasing pressure on that caliper and thus the sticking brake problem. But the tow truck driver had an idea that the left front wheel bearing was going out, causing the caliper to not set correctly and that caused my problem.
I guess I'm just wondering where to start and what to check first. I figure I'm going to go and replace all softlines, but the Bentley leaves a bit to desire on how to go through wheel bearings. How do I check those and where do I get replacements? EDIT (Bentley Chap 7, Page 8 )
Also, is there a good way to check my master cylinder and brake calipers? How can I tell if the heat and stress effected that caliper? Are good replacement calipers available if I need to replace those as well?
I purchased this squareback a few months ago and it is a great running vehicle. However, the tricky part of that is that I haven't replaced anything on it. I know the usual idea is to replace fuel lines and brake soft lines, but I figured this car was a bit of an exception due to it's condition. So given it's a 72 and my current condition, what should I get after on this car. I'm an ex T2 person, but now switched to T3 and could use some help on this one. _________________ 72 Squareback
9th air-cooled
Proud Member #8, SBS (Stock Bus Society)
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Gremlin Killer
Robert Bills wrote: |
The guys on this forum can talk you through any issues you may have. Don't give up on the fuel injection - your Type 3 will thank you. |
Last edited by werker on Sun Sep 25, 2011 11:13 am; edited 4 times in total |
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krusher Samba Member
Joined: September 24, 2002 Posts: 7652 Location: europe
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Posted: Tue Sep 20, 2011 11:26 am Post subject: |
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easy to check the wheel bearing:
Jack up car so suspect wheel is off the floor.
Take hold of tyre at top and bottom
Try to move top and bottom of wheel in and out. (in top out bottom, out top in bottom) You will feel it straight away if its loose.
If you also spin the wheel you should hear a loose or bad wheel bearing "rubble" (make a noise)
Start with that. _________________ (06:31:07) RoachGhia: "i drink dick way too fast" |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Tue Sep 20, 2011 11:30 am Post subject: |
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Definitely sounds like you brakes were dragging and overheated on that wheel. With the "wump wump wump" sound I would suspect bearings as well. If it were the wheel or master cylinder I'd think it would simply drag and heat up, unless it's really bad at the rotor warped, but then you'd also feel that warped rotor all the time.
The wheel bearings are easy to check. Just jack up the car, remove the wheel, remove the caliper then grab the center of the (covering the axle nut) rotor and "push-pull" on the rotor. If you feel any substantial movement they bearings are at least loose if not worn, there should be a max of .005 in play there.
The bearings, races and seals are readily available, I just did all 4 wheels on my 73.
From the point you would be above, with the wheel and caliper removed all you need to do from there is pop the cover off disk, loosen the allen bolt that clamps the axle nut onto the axle, then remove the axle nut. Keep in mind that the drivers side is left handed threads on the front wheel.
Replacing the bearings, races and seals is just a matter of pressing (or tapping with a hammer and punch) the races out then using a socket or pipe to tap the new races back in, greasing everything and re-assembly. The only technical thing on the re-assembly is that the wheel bearing play needs to be set to .005 in. Here's a pic of that being done with a dial indicator. BTW that is a squareback, I just studded the new rotors cause I hate fighting with the lug studs.
The Bentley does have all the specific info you need to do the job once you have the basic idea.
The easiest way to test the wheel and master cylinders would be to jack the car up, turn the wheel to feel the resistance, depress the brake pedal (and release it), then go back and turn the wheel again. If it sticks/won't turn either your wheel or master cylinder is probably sticking. From there you'll have to check the other wheels etc. to try and see if it's the master or that one wheel.
The brake parts are also available but you might have to dig a little more. I actually found some of them at O'Reily and some of them online when I did mine. |
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Tram Samba Socialist
Joined: May 02, 2003 Posts: 22697 Location: Still Feelin' the Bern- Once you've felt it you can't un- feel it.
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Posted: Tue Sep 20, 2011 3:17 pm Post subject: |
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sounds like a brake locked.
To check if it's the caliper or the hose, you'll need to replicate the problem, then open the bleeder on the affected wheel and see if the brake releases. *CAUTION* It will be hot!!!* If it does, your suspect is the hose. If it does not, your suspect is the caliper. (I'd replace the hose anyways- in fact, I'd go through the whole system.)
Now- check and repack the wheel bearings anyways, as the excess heat could have melted your bearing grease. _________________ Немає виправдання для війни! Я з Україною.
Bryan67 wrote: |
Just my hands. And a little lube. No tools. |
To best contact me, please use the EMAIL function in my profile |
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werker Redwood Wrencher
Joined: March 08, 2004 Posts: 308 Location: Separating the drum from the axle...
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Posted: Tue Sep 20, 2011 3:47 pm Post subject: |
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Thanks for the help. I'll start off by replacing the soft lines and inspecting/repacking the bearings. I'll keep an eye out for sticking etc. while bleeding and go from there. If the problem repeats, I'll crack the bleeder and see what happens. Thanks _________________ 72 Squareback
9th air-cooled
Proud Member #8, SBS (Stock Bus Society)
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Gremlin Killer
Robert Bills wrote: |
The guys on this forum can talk you through any issues you may have. Don't give up on the fuel injection - your Type 3 will thank you. |
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krusher Samba Member
Joined: September 24, 2002 Posts: 7652 Location: europe
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Posted: Wed Sep 21, 2011 12:43 am Post subject: |
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werker wrote: |
Thanks for the help. I'll start off by replacing the soft lines and inspecting/repacking the bearings. I'll keep an eye out for sticking etc. while bleeding and go from there. If the problem repeats, I'll crack the bleeder and see what happens. Thanks |
No you have this wrong way round, you use the methods we have given you to find the problem and fix it.
Not replace parts randomly, then do the checking. _________________ (06:31:07) RoachGhia: "i drink dick way too fast" |
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josh Samba Member
Joined: July 13, 2003 Posts: 1773 Location: laid back in the tall grass
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Posted: Wed Sep 21, 2011 11:56 am Post subject: |
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krusher wrote: |
werker wrote: |
Thanks for the help. I'll start off by replacing the soft lines and inspecting/repacking the bearings. I'll keep an eye out for sticking etc. while bleeding and go from there. If the problem repeats, I'll crack the bleeder and see what happens. Thanks |
No you have this wrong way round, you use the methods we have given you to find the problem and fix it.
Not replace parts randomly, then do the checking. |
I usually go about things with the same philosophy, but with brake hoses I strongly disagree. Unless the owner knows when they were replaced they are probably overdue. You can check and see if they were plugged when they are off anyway.
As for the hard parts definitely don't go around replacing old with new. Good rebuilt, OG calipers are way better than the new stuff that's out there. _________________
modok wrote: |
...If If stoner A takes a hit and then stoner B goes right away(not waiting two seconds), he's trying to suck on it while it's still got a vaccum, doesen't get much of a hit at all! Cause it hasn't filled back up all the way yet.
Stoner A is cylinders #2/4 B is #1/3 The plugged bowl is the throttle, the bong is the manifold |
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Bobnotch Samba Member
Joined: July 06, 2003 Posts: 22356 Location: Kimball, Mi
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Posted: Wed Sep 21, 2011 6:11 pm Post subject: |
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werke wrote: |
I'll start off by replacing the soft lines and inspecting/repacking the bearings. |
When you get the bearings out, look for spots of blueing on the races, not shiney areas, and pitting. The last 2 can are a definite need for replacement. Blueing indicates that it got hot, grease got boiled off, and the cause is probably from being too tight. Like I tell people, a tight bearing won't go 1,000 miles, but a loose bearing will go 10,000 miles.
You need to find out what's going one. Yes, a brake hose could be collasping internally, but it could have also been a tight bearing trying to fail. _________________ Bob 65 Notch S with Sunroof
71 Notch ...aka Krunchy; build pics here;
http://www.thesamba.com/vw/forum/viewtopic.php?t=249390 -been busy working
64 T-34 Ghia...aka Wolfie, under construction... http://www.thesamba.com/vw/forum/viewtopic.php?t=412120
Tram wrote: |
"Friends are God's way of apologizing for relatives." |
Tram wrote: |
People keep confusing "restored" and "restroyed". |
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werker Redwood Wrencher
Joined: March 08, 2004 Posts: 308 Location: Separating the drum from the axle...
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Posted: Sat Sep 24, 2011 5:04 pm Post subject: |
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I pulled the wheels off this morning and took a look around. The wheel bearings were on a bit tight, but nothing to bad and they looked just fine. Looking at the brake system, the softlines were ok, but I'll replaced them anyway. Both calipers were very sticky and hard to articulate. I pulled off the suspect one and the rubber boot seemed like it had melted a bit. Taking a clamp to the caliper, I was able to collapse it a some, but it took a lot of effort. I managed to rig up a bike pump to re-expand the piston, and on the 'good' passenger side caliper I got one piston to come out with about 60lbs. I cleaned that one up a bit, but noticed alot of sediment and deposits in the bottom of the chamber below the piston. I put that back in and then tried to get the other piston out. I hit about 100lbs and it didn't move so I stopped pumping. I put the pump on the bad caliper and neither piston moved with about 100lbs so I stopped again. What pressure does the brake system work at?
So my options are to rebuild or find new calipers. Ive got the mid-72 onward brakes and those calipers seem absolutely impossible to find. So I'll look at rebuilding unless somebody knows a good place to buy decent replacements.
Otherwise, it looks like I need 411698471 for the rebuild kit. So how do I get the pistons out?
Finally, after some searching, I sent an email to [email protected] to see if he still rebuilds calipers, just in case. Anybody know if he still provides this service? _________________ 72 Squareback
9th air-cooled
Proud Member #8, SBS (Stock Bus Society)
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Gremlin Killer
Robert Bills wrote: |
The guys on this forum can talk you through any issues you may have. Don't give up on the fuel injection - your Type 3 will thank you. |
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raygreenwood Samba Member
Joined: November 24, 2008 Posts: 21474 Location: Oklahoma City
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Posted: Sat Sep 24, 2011 5:22 pm Post subject: |
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The brakes work anywhere from about 20-600 psi. I know the rear brake proportioning valve on my 412 kicks in at 531 psi.
Just rebuild the calipers yourself. There is absolutely nothing to it. If they are crusty rust....no big deal...as long as major rust pits in the cylinder walls do not go up to, through and past the seal groove from the inside to the outside. If they do then fluid can bypass if the pits are over about .003" deep.
These are not like engine cylinders. There are no rings so the cylinder wall condition means little. Just go around them well with 240-320 grit wet dry. Then polish them with 800-1000 grit.
The piston is the part that must be smooth. Any pits or grooves on the sides of the piston that are long enough to span the sealing ring and over about .002-.003" deep can leak. If you have nothing but small pits...just polish the piston with 800-1000 grit wet dry....clean everything in very hot water and soap, blow dry, lube with brake fluid immediatley and assemble immediatley.
Its worthwhile having the caliper bodies soda blasted for about $20....don't worry it rinses away completely when you rinse them in water. All told you should be able to rebuild the pair for about $50-60 including soda blasting. These will be factory good...and better than most re-mans. I would pop for some speed bleeder screws they work very well. Ray |
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werker Redwood Wrencher
Joined: March 08, 2004 Posts: 308 Location: Separating the drum from the axle...
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Posted: Sun Sep 25, 2011 11:12 am Post subject: |
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Ok, sounds good. After digging around that one piston, it looks easy enough to go ahead an do for both calipers. The remaining question is how do I get the other pistons out? Should I use my brake system to get them out? Does that mean I need to re bleed my system to get each piston out? Any tips on the rebuilt that may save me a few steps? _________________ 72 Squareback
9th air-cooled
Proud Member #8, SBS (Stock Bus Society)
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Gremlin Killer
Robert Bills wrote: |
The guys on this forum can talk you through any issues you may have. Don't give up on the fuel injection - your Type 3 will thank you. |
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raygreenwood Samba Member
Joined: November 24, 2008 Posts: 21474 Location: Oklahoma City
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Posted: Sun Sep 25, 2011 11:45 am Post subject: |
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Go ahead and put plenty of penetrating oilaround the outer piston edge. Then heat it a bit and tap on it...add more pentrating oil. Then put the other piston back in...heavily lubed...and put the air to it again. Be careful. It will eventuallycome out. Ray |
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Robert Bills Samba Member
Joined: January 25, 2011 Posts: 284 Location: San Miguel de Allende, GTO, Mexico. Formerly from Area Code 530
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Posted: Sun Sep 25, 2011 4:13 pm Post subject: |
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When I bought my '73 Squareback in February 2011 (in storage for 14 years), the right side caliper was sticking. A search for a replacement turned up nothing in stock anywhere in the western states, so both sides were rebuilt.
AFAIK, Jim Adney still rebuilds them, and at a decent price too. _________________ Robert Bills
'73 Squareback [sold Feb 2013 ]; Now in search of a Type 181/Safari |
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krusher Samba Member
Joined: September 24, 2002 Posts: 7652 Location: europe
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Posted: Mon Sep 26, 2011 1:29 am Post subject: |
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if you have a welder, then weld a zerk/grease nipple to a metal hardline threaded end and you can push the pistons out with grease from a grease gun. (keep the caliper in one piece when you do this, when one piston is nearly out you need to stop it in it tracks to get the other one out while you can still make pressure)
I have reconed many bay window calipers this way, I 95% of the time use all the old seal as there better than the crap in the rebuild kits.
Usually wire/steel wool with clean up the piston and inside of the caliper body. _________________ (06:31:07) RoachGhia: "i drink dick way too fast" |
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werker Redwood Wrencher
Joined: March 08, 2004 Posts: 308 Location: Separating the drum from the axle...
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Posted: Thu Oct 13, 2011 10:37 am Post subject: |
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So, I finally got a rebuild kit for my calipers. I rigged up the tool below to get the pistons out. Rebuilding the caliper was much easier than I thought and now the brakes are great. I'll assume the problem was fixed.
Thanks for the help,
_________________ 72 Squareback
9th air-cooled
Proud Member #8, SBS (Stock Bus Society)
---------------------------------------
Gremlin Killer
Robert Bills wrote: |
The guys on this forum can talk you through any issues you may have. Don't give up on the fuel injection - your Type 3 will thank you. |
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supaninja Samba Member
Joined: July 03, 2010 Posts: 4020 Location: houston
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edatoakrun Samba Member
Joined: August 14, 2014 Posts: 9 Location: Shasta County
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Posted: Thu Aug 14, 2014 1:27 pm Post subject: |
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raygreenwood wrote: |
Go ahead and put plenty of penetrating oilaround the outer piston edge. Then heat it a bit and tap on it...add more pentrating oil. Then put the other piston back in...heavily lubed...and put the air to it again. Be careful. It will eventuallycome out. Ray |
I've got three of four pistons stuck on my 72 SB.
By the looks of it, two were stuck long before the car was last driven in ~'02, as pads were all the way to metal on one side of each disk, and the other side pads were barely worn.
I can tap/push the three pistons further in, but ~100 lbs air pressure will not budge them out.
I'll let them soak some more, then try heat (propane torch to caliper?).
Any other suggestions?
The one piston I got out looks ok.
Does it sound like the calipers will be rebuildable, even if I can get the pistons out? |
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Mike Fisher Samba Member
Joined: January 30, 2006 Posts: 17962 Location: Eugene, OR
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Posted: Thu Aug 14, 2014 2:02 pm Post subject: |
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Rebuild your original German calipers rather than buying rebuilt from China or wherever. Jim Adney can rebuild them for you. Find him in the Type 3 chat room at [email protected] _________________ https://imgur.com/user/FisherSquareback/posts
69 FI/AT square Daily Driver
66 sunroof,67,70,71,71,71AT,72,72AT,73 Parts
two 57 oval ragtops sold
'68 Karmann Ghia sold
Society is like stew. If you don't keep it stirred up you end up with a lot of scum on the top! - Russ_Wolfe/Edward Abbey |
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Erik G Samba Member
Joined: October 16, 2002 Posts: 13247 Location: Tejas!
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Posted: Thu Aug 14, 2014 2:12 pm Post subject: |
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I did the calipers on my Porsche, which are very similar. I used a grease gun to pop mine out. Messy but it works. you can soak them in a rust buster like deep creep (seafoam brand) and might get more luck with the air. I got mine out by removing the bridge pipe, plugging various holes with brass inserts, etc. Don't be afraid to soak them a while, squirting your favorite rust breaker (not WD-40) |
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Bobnotch Samba Member
Joined: July 06, 2003 Posts: 22356 Location: Kimball, Mi
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Posted: Thu Aug 14, 2014 6:17 pm Post subject: |
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Erik G wrote: |
I did the calipers on my Porsche, which are very similar. I used a grease gun to pop mine out. Messy but it works. you can soak them in a rust buster like deep creep (seafoam brand) and might get more luck with the air. I got mine out by removing the bridge pipe, plugging various holes with brass inserts, etc. Don't be afraid to soak them a while, squirting your favorite rust breaker (not WD-40) |
Jim uses a water and air pressure set up to force the pistons out. He's got a system that really works great. But, if the bleeder screws are broke, you should look for another pair. Keep in mind that 72 calipers are the same as 411 and early 914 Porsche calipers, so that should help you find a pair.
To contact Jim directly, try e-mailing him at [email protected] . _________________ Bob 65 Notch S with Sunroof
71 Notch ...aka Krunchy; build pics here;
http://www.thesamba.com/vw/forum/viewtopic.php?t=249390 -been busy working
64 T-34 Ghia...aka Wolfie, under construction... http://www.thesamba.com/vw/forum/viewtopic.php?t=412120
Tram wrote: |
"Friends are God's way of apologizing for relatives." |
Tram wrote: |
People keep confusing "restored" and "restroyed". |
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