Brake master cylinder overhaul #4

I disassembled the brake master cylinder again I repaired on the other day because the behavior of the piston seemed to be not smooth enough.

When I removed the piston at the last time, I checked the condition of the rubber and it looked good. Therefore, I reassembled it without replacing the rubber.

However, again I disassembled the brake master cylinder’s piston and checked its condition carefully in order to reassure myself.

I disassembled and cleaned the piston and the spring.

The condition of the original rubber was not bad, but I replaced it once with the rubber part of the repair kit.

Again, however, I felt that the quality of the rubber parts of the repair kit (left one) seemed to be poor….

I also assembled the piston into the cylinder as a trial, however, the tight contacting feeling was not enough.

As my conclusion, I judged the condition of the original rubber parts were good enough and decided to reuse them.

So, I reassembled with the original rubber parts again.

When I was reassembling the brake master cylinder, I felt very slight resistance in the movement of the piston.

I checked the inside wall of the cylinder with my finger very carefully and found there was a very small step in the smooth surface.

I honed the inside of the cylinder again and polished with #2000 sand paper to make the surface flat. Then, the movement of the piston became very smooth.

I thought now it should be okay. I would try a test drive with this, if it would be not good, I would replace it with a new part at that time.

(My original blog was written on 25th Jun 2009)

Comments

Tip to repair rubber parts

I disassembled the rear axle before. There had been no progress on it because I started the repair of the fuel tank during my summer holiday. While painting the fuel tank , I repaired the torn rubber boot of the parking brake wire. I guessed it didn ’ t cost high because it was small rubber part. But I wanted to try the repair method I read on the magazine article before. This was the condition before the repair. The rubber was torn apart and separated almost. I used this self-adhesive type butyl tape. I pasted lots of small pieces of the butyl tape on the back side of the rubber boot. As time goes by , these tapes would melt and stick together. After this I applied plenty of adhesive “ Super X Black ” on the rubber boot. On the magazine of MOTO MAINTENANCE , I read the article that the motorcycle seat was repaired with this method. So , I wanted to try it. After drying 1 day , it became like this....

Pad spring repair

One of the springs to hold the brake pads was broken. At first I thought to buy it, however, I tried to fix it using rivets. It seemed to be strong enough just to hold pads. Later I removed the rust and cleaned them. Note: I have been using this repaired pad soring for 10 years and there is no issue. Pad spring is not an expensive part ptobably (I don't know the exact price), but it is easy to repair if you have ar1750gtv hand rivetter. (My original blog was written on 10th May 2008 )

Body repair around the fuel tank

I found some rust at the flange in body around the fuel tank as I expected. I believed this level of rust in this area was quite usual for old Alfa Romeo. It seemed that this area didn ’ t influence on the body strength , however , I was considering the method what I could do by myself. Anyway in order to prepare the sheet metal for the repair at first , I started to look for the store where I could buy some sheet metal near my house. I tried to research the store on internet , but I couldn ’ t find appropriate stores. Finally I asked the person at repair shop , who did maintenance of my Renault 5 , about the store I could buy some sheet metal. They kindly taught me the store , but at the same time they gave me some sheet metal for free. That was enough volume for what I wanted to do. I didn ’ t expect it. Thanks a lot!!! (My original blog was written on 12th Sep. 2008 )

The day my "onboro ALFA" would revive

Search This Blog