PM miniron, he knows all about the MK1 servos.
| ausmini https://www.ausmini.com/forums/ |
|
| MK1 Brake Booster Dissassembly https://www.ausmini.com/forums/viewtopic.php?f=2&t=34742 |
Page 1 of 3 |
| Author: | Mick [ Sun Aug 12, 2007 5:51 pm ] |
| Post subject: | MK1 Brake Booster Dissassembly |
Can anyone tell me how to pull apart the MK1 Brake Boosters? I have the diaphragm housings off, the air valve chamber and everything else down to the cast iron main body of the servo. The problem is how to remove the bung that is in the end of the body and keeps the piston and spring etcetera within the unit. It seems to be pressed in and a little difficult to remove. Any tips? Also, was the cast iron body gold-zinc plated or only the big diaphragm housing? Are the rebuild kits available for these early servos, I've only ever rebuilt the later types. I've got a zinc plater near my place who will do a batch job for 55 dollars, but wants 35 kilos of mini bits to do it (something about coming out a nicer finish if there's more in there or some other black magic), so I'm trying to make up the 35. I'll cut up star pickets if I have to but will try to make it up with legitimate minibits first! cheers Mick |
|
| Author: | 64cooper [ Sun Aug 12, 2007 8:26 pm ] |
| Post subject: | |
Mick had the same problem with a VH44 servo last week. Dismantled it down as far as I could go then soaked the collar area in WD40. The plunger was free in operation so I bolted the the plunger onto a solid piece of steel held in a vice and used the reverse action on the plunger by dragging the body to try and pull it out. It eventually worked out. Did you get the air valve plunger out of the body? |
|
| Author: | Mick [ Sun Aug 12, 2007 9:05 pm ] |
| Post subject: | |
Ahh, that's what it's called. Nup it's jammed in there. Any hints on that bit ap art from lots of WD? i don't think these were made for being rekitted, they look awfully like a single use unit to me...but I will stick at it. I got the collar out by getting a same diameter phillips screwdriver into the hole and wiggling it. It moved a little and with that movement it jacked one side up a tiny amount. I jammed a sharp screw driver in the corner and wiggled against the high side which jacked up the other side a little. So slowly slowly I got it out. Still got to get the plunger out however....any idea on the finish of the original bodies? the bell housings were gold zinc plated I can see on the inside. |
|
| Author: | drmini in aust [ Sun Aug 12, 2007 9:15 pm ] |
| Post subject: | |
PM miniron, he knows all about the MK1 servos.
|
|
| Author: | Mick [ Sun Aug 12, 2007 9:28 pm ] |
| Post subject: | |
Ok will do. Are the rebuild kits still available? |
|
| Author: | drmini in aust [ Sun Aug 12, 2007 9:38 pm ] |
| Post subject: | |
Can't see the repair kit in Karcraft's catalog now, they used to carry one of the 2 Lockheed servo kits. ask them- email [email protected] |
|
| Author: | 64cooper [ Sun Aug 12, 2007 9:44 pm ] |
| Post subject: | |
Mick I popped the air valve out before dissassembling the servo (the air valve assembly was dismantled) by hooking a clutch master cylinder up to the inlet and putting a bleed nipple into the outlet and then just bled the setup to get pressure and then just applied more pressure and out it pops. Just make sure that you have something covering the unit so that it doesn't fly off into the never never. I don't know about kits for them. The VH44 kits are still available though. cheers |
|
| Author: | Mick [ Sun Aug 12, 2007 9:53 pm ] |
| Post subject: | |
This booster was a bit of a rusticle, and it hadn't been hooked up for many years either so very little budged. The plunger is the last bit to come out so I'll keep at it for now. The main diaphragm is good and I reckon the rest of the seals might be found out of other applications if I ask a specialist. The air valve diaphragm is the main one I'm worried about as it is a one piece design . It didn't need to be busted either had I been patient enough 
|
|
| Author: | Mick [ Sun Aug 12, 2007 9:59 pm ] |
| Post subject: | |
AHA! But no air valve parts..... http://www.minimania.com/web/like/y/ite ... Detail.cfm |
|
| Author: | Mick [ Mon Aug 13, 2007 9:47 am ] |
| Post subject: | |
That air valve piston is a pain in the arse.... I've got compressed air behind it now, but it's still not enough. It needs a hydraulic persuasion I am thinking, but I'll try and keep at it. WD40 probably wouldn't be a good idea would it? Doesn't it swell the seals? |
|
| Author: | kiwiinwgtn [ Mon Aug 13, 2007 7:08 pm ] |
| Post subject: | |
try this, will not do any damage, may take a week i use to clean really rusty stuff it is used in the ship industry http://www.stovebolt.com/techtips/rust/ ... usting.htm as for taking the booster a part becareful as the rod and piston are no longer available if you stuff it Kiwiinwgtn |
|
| Author: | Mick [ Mon Aug 13, 2007 7:41 pm ] |
| Post subject: | |
You know I've thought about that, I've got what is called a Lambda power supply, it can put out any voltage between 18 and 28 volts, and up to 20 amps continuously. Do you mean the piston on the air valve or the main piston in the body? |
|
| Author: | Mick [ Mon Aug 13, 2007 10:15 pm ] |
| Post subject: | |
I had a brain wave tonight, strong enough to make a small globe glow dimly. I stuffed the master cylinder with grease, and jimmied a grease nipple onto the end of a grease gun. I'm not sure how many PSI a grease gun can provide but figure it would be one metric shitload. So away I pump, pump, pumpitty, pump, pump, pump..... and all seems to go swimmingly with heaps of pressure, but still no go. The paper gasket on the bottom is letting me down at the moment. I've got to figure a better way.... i can get a portapac I am sure from coates or similar, but how can I get it to pressurise this thing to push the air valve piston out? Don't hassle me about the bench either, there's four mini related projects going on concurrently (two pairs of SU's being reconditioned, the booster and pulling down the Cooper shell ) 
|
|
| Author: | drmini in aust [ Mon Aug 13, 2007 10:27 pm ] |
| Post subject: | |
Be careful Mick, a decent grease gun is good for 5,000-10,000 psi... 
|
|
| Author: | Mick [ Mon Aug 13, 2007 10:33 pm ] |
| Post subject: | |
drmini in aust wrote: Be careful Mick, a decent grease gun is good for 5,000-10,000 psi...
yeeeaaaahhh that's what I'm talking about! I'm gonna make that piston wish it was never born. |
|
| Page 1 of 3 | All times are UTC + 10 hours |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|