Brake Booster and Master Cylinder

[ak1234]

John .... not sure your going to want to PACK the rear wheel bearings ... there is a grease fitting on top of the rear upright ..pumping grease into it should take care of that procedure.
   
   Oh ..I foudn the booster ... the boys were correct its from a sierra .. only one problem ..there is one on ebay but he will not ship to the US ... bonehead.  The search continues.
   
   Ron

[nikbj68]

Ron. send me the item number & I`ll buy it & ship to you. No problem.

[dkp_cobra]

quote:Originally posted by jbottini
   
Peter,
   I'm planning on evaluating brakes this weekend...your observation is in line with mine. As to rear wheel bearings, I need to re-pack, not replace. your experience there could be helpful. do you have more details of that procedure than are on the "rebuilding" site/
   Jim
   

   
   Jim,
   
   here comes a short description of what I did. It's not professional but it worked with the tools I had at home.
   
   The original bearing spacer were made of normal construction steal. That
   was to mild. Now, my turner made me spacer using C45 steel. But I guess
   this is a german DIN standard. It's an non-alloyed high-grade steel with
   a carbon content of 0,45 mass percentage. That should be ok.
   
   So, you need a bearing spacer with a thickness that is a little bit too
   big so you can grinding it to the perfect thickness. Of course the
   thickness of the two different spacer (left and right) will be different
   in general. I think a thickness of 17mm should be ok for a starting
   point. The I.D. should be s.t. the spacer has no tolerance on the hub
   but you should be able to remove it by hand. The O.D. was 1 7/8".
   
   Step 1: put all the things together (with grease) but without the
   spacer and dont use the bolt for the rear drive flange. Press the
   flange simply by hand as far as you can but without big power. The roles
   of the bearing shouldn't be pressed strongly to the hub carrier. Now,
   put the assembled hub into a wheel and measure the torque you need to
   start turning the hub. You should use a spring scale for that job.
   Please look at the following picture what I have in mind:
   
   
   
   The idea behind this task is to get a reference value for the torque you
   need to turn the wheel when there is no (or nearly) no pressure on the
   bearing.
   
   Step 2: put all together with the spacer and the bolt for the rear
   drive flange and torque it nearly to it's final specification. The hub
   carrier should have a certain tolerance on the hub because the spacer is
   to thick s.t. the bearing rolls are pressed to the hub carrier. If you
   have no tolerance the initial spacer was to small. How you you test the
   tolerance? Unfortunately, I don't have a picture of that and I don't
   want to remove the hub carrier from my car. I mounted a leverage of ca.
   60cm at the hub carrier and put it into the wheel and torqued the wheel
   nut. Now, if you fix the wheel you have the power by the leverage to
   check the tolerance of the hub carrier wrt. the hub.
   
   Step 3: remove the bearing spacer and grinding let's say 0,003". I used
   sandpaper for that. If you do it by hand you will probably slope it. I
   used this simple but effective way:
   
   
   
   
   
   In order to measure whether you really has only 0,003" removed to should
   use a micrometer. If you don't have one you get it for some euros at ebay.
   
   
   
   Step 4: repeat step 2 and step 3 until there is no tolerance of the hub
   carrier to its hub. (I guees you will repeat this 5, 10 or 15 times).
   Please check each time the torque you need to turn the hub carrier and
   compare it with your reference value from step 1. It shouldn't increase
   too much.  You are finished if there is no tolerance and the wheel turns
   easily.
   
   Step 5: repeat everything for the other side

[ak1234]

nikbj68 Thanks and very resonably priced .... Item number: 390048635493
   
   Let me know I will send you the money.
   
   Ron

[jbottini]

AK1234 Ron, what is Sierra part number for booster?? Have you found master cylinder? I can not locate it with "G" number above. Jim 1113

[ANF289]

quote:Originally posted by jbottini
   
AK1234 Ron, what is Sierra part number for booster?? Have you found master cylinder? I can not locate it with "G" number above. Jim 1113
   

   
   Jim:
   Ford Sierra Mk1 / Mk2 Brake Booster Servo 'Girling'
   1982 - 15/2/1993
   Ford Part Number 6195975
   Art
   
   Another one at:
   http://cgi.ebay.com/Ford-Sierra-MK2-New-G-Ford-brake-booster_W0QQitemZ310116417599QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item483461003f&_trksid=p3286.m63.l1177

[nikbj68]

quote:Originally posted by ak1234nikbj68 Thanks and very resonably priced .... Item number: 390048635493
   Let me know I will send you the money.
   Ron

   Hi Ron.
   Just checked, and they do ship worldwide, although it`s not in the 'shipping info' on the auction page. If you follow the link to their Ford Parts UK site there are details, so this would save you the cost of me having to ship it here and then on to you.
   
   The shipping looks likely to be around $50 by my calculations...so maybe armed with a part number you could find the servo closer to home?
   Good luck, whichever way this works out.[:)]

[ak1234]

I emailed them thru ebay and he insists that he will not ship it .. bozo !  Anyway if you get the message in time bid it and I will pay for it and shipping.
   
   Thanks Ron

[nikbj68]

OK Ron....will do. Sorry to have led you astray on what looked like clear information!

[nikbj68]

Root Cause Analysis time.
   
   I found an interesting article about servo problems, and there was this statement attached:
   
   Reproduction of a warning note from AP Lockheed on problems with silicone fluids in braking systems
   
   Silicone brake fluids - beware
   Our technical service department is receiving an alarming number of calls from motorists reporting problems with silicone fluids. AP Lockheed neither markets such fluids nor recommends their use with our own or any other braking system.
   
   Virtually all the problems relate to long/spongy pedal, sudden loss of brakes and hanging on of brakes. They reflect certain properties of silicone fluids identified by us over many years and recently ratified in SAE publications, namely high ambient viscosity, high air absorption, high compressibility, low lubricity and immiscibility with water. Research has shown that the relationships between problems reported and properties identified may be expressed as follows:
   
   Long/spongy pedal
   o Compressibility, up to three times that of glycol based fluids.
   o High viscosity, twice that of glycol based fluids, leading to slow rates of fill and retention of free air entrapped during filling and hence bleeding difficulties.
   
   Sudden loss of brakes
   o Air absorption - gasification of absorbed air at relatively low temperature produces vapour lock effect.
   o Immiscibility (failure to mix) with water - whilst the presence of dissolved water will reduce the boiling point of glycol based fluids, any free water entrapped in silicone filled systems will boil and produce vapour lock at much lower temperatures (100C or thereabouts).
   
   Hanging-on of brakes
   o Low lubricity - in disc brake systems the sole mechanism for normalisation if system pressure upon release of pedal pressure is a designed-in tendency of seals to recover to their "at rest" attitude. Low lubricity works against this tendency.
   o High viscocity, exacerbating the above effect.
   It should not be assumed, therefore, that the high price of silicone fluids implies higher performance in hard driving or even normal road use.
   AP Lockheed glycol based fluids do not contain the adverse properties described above. The recently introduced Supreme DOT 5.1, which exceeds the performance criteria of DOT5, is suitable for all conditions likely to be encountered in modern driving conditions.
   
   It is of course possible that a company that sells millions of pounds worth of 'after sale' replacement brake parts & fluids would be disinclined to embrace a no/low maintenance product, but it is a contentious subject worthy of further examination, at least.

[dkp_cobra]

One remark concerning the Ford Fiesta brake booster. Before everybody of you starts bidding and buying Fiesta brake booster on ebay please have a look into your car whether you have such a booster. In my quite early MK IV (AK 1029) is a Triumph TR6 booster.
   
   Peter

[nikbj68]

TR6 is a strange choice, having been out of production since 1976...the Sierra part(not Fiesta) was at least a current vehicle at the time(although that doesn`t make finding the parts N.O.S easy now, 20+ years on!!!)
   
   

quote: Posted by Peter DKP: The brake master cylinder is from Girling. The number is: G 64679152Q123 X...I have the 7/8".

   Is this the number for your TR6 item or the Ford part, Peter?

[dkp_cobra]

Sierra, not Fiesta. I am sorry (everybody who drove both know what I mean). My booster has the same dimension as the booster of a TR6. The advantage is that it is no problem to get a replacement.
   
   The number G 64679152Q123 X is stamped on the master brake cylinder. The TR6 I looked today had a different number. So I don't know where it comes from. My contact person at TRW/Girling had no problems sending me the correct repair set for that master brake cylinder.

[jbottini]

I'll check my master cylinder tonight for a part or casting number (as I think the G number may be) I can't make sense with any American Girling suppliers for a rebuild kit or replacement master, so I may ask you to buy me a rebuilt kit AND a master and send to me.

[nikbj68]

OK. I`ve had a guy cross reference the casting number "G 64679152Q123" and it is actually for a `72-`76 MkI Ford Granada. Original Girling part number 64066627, new reference PMH117.