[Fishmyster]

Hi all, I am rebuilding the brake sytem on my 330i Touring and wanted to know if anybody knows how to replace the rubber brackets around the piston chamber on the caliper housing. I accidentally damaged the rubber seal and thought it would be senisble to replace them if i was upgrading to racing pads and discs.

According to realoem.com http://www.realoem.com/bmw/showparts.do?model=AW52&mospid=47673&btnr=34_0757&hg=34&fg=05

I can buy a REPAIR SET BRAKE CALIPER kit but have no clue about how to fit them? Any help or instructions would be really appreciated!:dunno:

 

[jcourcoul]

Only caliper rebuilding DIY I have been able to find is this:

http://www.bmw-m.net/TechProc/caliper.htm

Since I have the suspicion of a sticking caliper, I have ordered the seal kit as well as the mount bushings kit. Hopefully they will arrive this week or the next, what with the Mexican Peso parity gone down the crapper...

 

[ffej]

I used that DIY from Bob Strommel that you posted when I did the cailpers on my 98 and it worked. It's just a little tricky, is all.

Good luck!

 

[Scott ZHP]

Keep everything spotless. Use lots of CRC.

Front or rear calipers???

 

[jcourcoul]

I used that DIY from Bob Strommel that you posted when I did the cailpers on my 98 and it worked. It's just a little tricky, is all.

Dunno, this is one of those occasions where I keep remembering Orlando Jones' line from the movie Evolution: "there's always time for lubrication!!!"

 

[ffej]

Dunno, this is one of those occasions where I keep remembering Orlando Jones' line from the movie Evolution: "there's always time for lubrication!!!"

:bustingup

 

[Scott ZHP]

:bustingup

Love your hood prop, BTW...

 

[ffej]

Love your hood prop, BTW...

Thanks, it's custom made. I can make one for you, too, and it only costs [shoots over to bimmerworld to check JRZ prices...] $4500! A bargain at twice the price

 

[Fast Bob]

You need compressed air to remove the piston. Basically, put the gun in the brake line hole and blow air in. Put a scrap of 2x4 in the caliper, so that the piston doesn't fly across the garage. Be very careful, they tend to "pop" out (you can hardly see the scar on my right middle finger any more).
If the cylinder is not bad, you can use a scotchbrite pad to clean it up, otherwise you need a 2 prong cylinder-bore hone. 3 prong is usually too big. Don't hone a lot, or the seal won't be tight. Use brakeclean, and make sure to let everything dry

Wear Nitrile rubber gloves. Lube the seal grooves with fresh brake fluid, then do the same with the seal, and push it into place (be careful, they`re slippery). Here`s a *real* backyard tip to make it easier to get the piston back into the bore....take the plastic top from a can of spray paint, and with a utility knife, cut around it`s circumference so you have a strip about an inch wide....now, cut the strip 90 degrees to the cut you just made (i.e., "break the circle") Curl the strip into a small circle, and insert it inside the rubber seal, and use it as a "funnel" to slide the piston through the seal without disrupting everything.

Use a torch on the bleeder bolt if it is stuck, don't use too small of an easy out once it breaks off (don't ask ;-).

 

[jvr826]

To add to what Fast Bob said, be certain the cylinder goes in perfectly straight.

 

[Fishmyster]

Fastbob +others, Thx brilliant i am going to get straight on to it in the morning! have ordered the replacment piston seals and dust covers so looking all good hopefully!

Thx again for the help!

 

[dakarm]

one tip. when you use the compressed air to push the piston out, put it in a big zip lock bag. it will keep the mess to a min.

 

[smolck]

You need compressed air to remove the piston. Basically, put the gun in the brake line hole and blow air in. Put a scrap of 2x4 in the caliper, so that the piston doesn't fly across the garage. Be very careful, they tend to "pop" out (you can hardly see the scar on my right middle finger any more).
If the cylinder is not bad, you can use a scotchbrite pad to clean it up, otherwise you need a 2 prong cylinder-bore hone. 3 prong is usually too big. Don't hone a lot, or the seal won't be tight. Use brakeclean, and make sure to let everything dry

Wear Nitrile rubber gloves. Lube the seal grooves with fresh brake fluid, then do the same with the seal, and push it into place (be careful, they`re slippery). Here`s a *real* backyard tip to make it easier to get the piston back into the bore....take the plastic top from a can of spray paint, and with a utility knife, cut around it`s circumference so you have a strip about an inch wide....now, cut the strip 90 degrees to the cut you just made (i.e., "break the circle") Curl the strip into a small circle, and insert it inside the rubber seal, and use it as a "funnel" to slide the piston through the seal without disrupting everything.

Use a torch on the bleeder bolt if it is stuck, don't use too small of an easy out once it breaks off (don't ask ;-).

That sounds like a heckuva lot more trouble than just paying $50 for one that has already been rebuilt......