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| | | | Joined: Oct 2010 Posts: 111 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2010 Posts: 111 | Ok...so I rebuilt what I thought a was a master cylinder in good shape for my '48, cleaned, new rebuild kit, so on. Installed new brakes, lines, rebuilt wheel cylinders. Poured in brake fluid, adjusted brakes, started slowly pumping pedal to fill lines and cylinders. Before I got to bleeding them, I pushed on the pedal firmly, and blooey! Blew the back of the reservoir top section out. It looks like a plug of some kind as the hole is simetrical(sp). Did I overlook something? Probably a new cylinder in order! | | | | | Joined: Sep 2006 Posts: 3,596 'Bolter | | 'Bolter Joined: Sep 2006 Posts: 3,596 | There is a clip that holds this all together if it blew out the clip failed or it over pressurized. If you search the topics here most will tell you they bench bleed these before installation it should help avoid what you encountered. I bench bled mine in the truck by bending a temp steel line that I put in the discharge fitting and then bent around to the fill reservoir I then slowly pumped the pedal while slowly adding fluid until I had all the air out of the MC. Removed the line hooked up to the system line and then bled the brakes beginning with the farthest from the cylinder in line distance. Never had one blow out like that on me. I am sure others will comment but it may be worth a search. | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Sounds like Fan blew the core plug out of the reservoir. Weird. I have never seen or heard of that happening. The only thing I can figure could cause that is the vent in the cap is stopped up. I generally bleed them with the cap loose. You can put it or a new one back in. It is like a freeze plug. It would be best to pull in off to make sure it is secure & leak proof.
Last edited by Wrenchbender Ret.; 11/18/2010 12:34 AM.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Oct 2010 Posts: 111 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2010 Posts: 111 | Brad
The only clip I saw was the one that holds the bottom pump and seal components together. This hole is on the back of the top reservoir half.
I have pulled it off. I figured I would have to replace the cylinder. The cap was on tight, It did not seem to build pressure with it loose. Is this "core plug" available, or should I buy a new cylinder?
Last edited by bowtiefan; 11/18/2010 2:39 AM.
| | | | | Joined: Dec 2001 Posts: 14,522 Moderator: Welcome Centre, Southern Bolters, Legion Hall | | Moderator: Welcome Centre, Southern Bolters, Legion Hall Joined: Dec 2001 Posts: 14,522 | If your cylinder is the same as my 52 1/2 ton panel drop me a PM. | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | You can get a freeze plug of the same dia. at a parts store.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Oct 2010 Posts: 111 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2010 Posts: 111 | Just put a new MC in...works alot better than my old one. Also, completely cast on the back of the reservoir - no plug. Anyway, bench bled, installed and bled all brakes...But... pedal still goes to floor after waiting a few seconds after pumping. No air comes from any wheel! Pedal will pump up about half, then fade quickly if let sit. Do I still have air somewhere I can't get out? | | | | | Joined: Dec 2003 Posts: 1,144 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 1,144 | check wheels to see if you have any wheel cylinder leaks. Had a new repro leak but only after I had fixed other leaks.
Last edited by kb3csw; 11/28/2010 1:55 PM.
| | | | | Joined: Jan 2009 Posts: 1,644 Shop Shark | | Shop Shark Joined: Jan 2009 Posts: 1,644 | Make sure you have the brakes adjusted all the way up,could be part of the problem.
Pete | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Those old Huck brakes are tricky to adjust. Remember the adjusters are all right hand threads. Adjust adjuster till you get a heavy drag.Then back itup about 4 clicks. There may still be some drag but that's ok. When those brakes are right the pedal will barely go down. You just apply pressure to it.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | |
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