Master cylinder help needed

[jmorris]

Hi guys
Changed my abs pump on the weekend and bled it all ok. i have now noticed that if i hold my foot on the brake pedal it slowly drops to the floor.i have hear this is a main symptom of knackered MC seals. i have been looking at getting a new one but when i phone suppliers (including VW) they say there is a choice of two.(22mm and 23.8)i have looked for a part number on the MC but cant find one, i have a Part number for the servo (1h2614105j) but i cant seem to cross reference it against the MC. is there a way of finding out the bore without taking it off the car? the only numbers i can see on it are 27, 8 ,85  which are circled (3 in total)
any help would be much appreciated
jake

[Wayne]

I believe 22mm is more common but the only way to know 100% is to measure it or get both and return the wrong one.

[cobalt6700]

I have to say I wouldn't bother with getting new seals.

I tried to get my MC apart after it went the day before a trackday - it's really not easy. Infact, even after trying a few days later all I managed to do was break the plastic seal on the back.

I just found myself a low mileage one on eBay.

[jmorris]

thanks for the help guys, just ordered one from ebay.Just hope its the right bore!
jake

[harlemex]

Hi guys
Changed my abs pump on the weekend and bled it all ok. i have now noticed that if i hold my foot on the brake pedal it slowly drops to the floor.i have hear this is a main symptom of knackered MC seals. i have been looking at getting a new one but when i phone suppliers (including VW) they say there is a choice of two.(22mm and 23.8)i have looked for a part number on the MC but cant find one, i have a Part number for the servo (1h2614105j) but i cant seem to cross reference it against the MC. is there a way of finding out the bore without taking it off the car? the only numbers i can see on it are 27, 8 ,85  which are circled (3 in total)
any help would be much appreciated
jake

Just wondering, how did you bleed the abs pump?

[jmorris]

i have full vagcom (VCDS)  just followed the instuctions on there.
jake

[harlemex]

cool. I might have to get that, how does one purchase and how much, i have the basic vagcom and i take it this isnt the same thing?! Cheers.

[jmorris]

i have vcds lite as i have a cheap ebay lead
http://www.ross-tech.com/vcds-lite/download/index.html
i bought the license for $99 (£60ish)
http://www.ross-tech.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=VCDSLiteReg&Category_Code=VAGCOM
worth every penny,compared to what vw charge per hour
hope this helps
jake

[harlemex]

thanx again and cheers for the link.