Brake Calipers - pistons rusted in

[AAB]

Finished the complete brakes job,..new pads, new front disks, new rubbers,new hoses,new master cylinder,..my fancy new air pressure bleed system worked like a dream, much to the delight of my wife who did all of the pumping 10 years ago.

Only one problem,..the plastic cylinders in the master cylinder, that actuate the warning light are half full of brake fluid !! .. I assume that this is a " No No ".

Also, according to the manual, pre March 1974 rear chambers have a 42 mm contact insert. The front is supposed to be 58 mm.

My chassis number is 116 033 22 027443 so can anyone advise me if this is pre or after March 1974 please ?

Regards,

Alex

 

[Styria]

Good stuff, AAB. It looks as though you obviously had no problems getting out the caliper pistons - that's if you went that far. Maybe should check your post again !
So obviously, if you have designed a "NEW" brake bleeding system, you may wish to share that with us although, with you mentioning "the boss", the system may not all be that revolutionary.

Sorry that I can't help you with the chassis numbers. I am just trying to remember which website has the production figures - gosh, the old brain isn't working. Mind you, I am quite confident that there are more capable members on 'topklasse' that are likely to come up with the correct advice. Regards Styria

 

[AAB]

Styria,..had no problems with the pistons.

My " new " air bleeding system consisted of using my handyman compressor unit, ( 100 psi ), & a well used but surplus pressure control valve from our home beer barrel to get about 2 bar.

I roped the reservoir down to the master cylinder just in case the pressure may decide to cause a " lift off " of the reservoir.

I have located a used pair of floats in pristine condition, complete with rubbers,pins etc

When I took a half full float into the local Benz dealer, they just looked at me & said " what does this do ? " !!!

I cannot believe this, as there must be thousands of W116 cars about.

Regards,

Alex

 

[AAB]

I have just received an e.mail from " rockauto.com ", a Yankee supplier of Benz parts that I have used on many occasions,..with total satisfaction.

They currently have a line of 450SEL 74 model, brake parts etc, from a supplier that is discontinuing production.

When the Aussie dollar was up in the 90 c per US dollar last year, new parts were extremely cheap,..& postage was often dearer than the part.

Regards,

Alex

 

[Styria]

There is a good supply of brake and caliper parts in Sydney, consequently I have no need to purchase those elsewhere.

Apart from the various methods that can be used to extract the caliper pistons, there is also the matter of re-assembly. In my case, I have always used Castrol Rubber grease for many years. However, the product in some ways is nowadays 'old hat' - we don't use a Commodore 64 computer any longer, do we ? I had noticed on occasions that whilst it may initially assist in re-fitting caliper pistons, the grease does become 'hard' and unyielding and it certainly does not prevent the formation of rust between the caliper housings and the pistons.

No, there is a much better product on the market, and it is specifically designed to assist in the assembly process. It is simply called "Caliper Assembly Oil" and can be purchsaed from DBA. I also sell the stuff at $18.00 a bottle, and the quantity would be sufficient to assemble about thirty calipers - in other words, 60 cents a "throw". Regards Styria