1 leaky front master cylinder and dowty washers Sat May 22, 2021 9:36 am
tinyspuds
Life time member
Greetings,
Noticed an intermittent loss of front brake pressure. Bled the brakes which seemed clear of air. During the process I noticed that operating the lever made a wet air sound at the m/c piston. No obvious leaks of fluid in the area but I sprayed contact cleaner over the join of M/c to twist grip housing which bubbled under pressure. Assume I have a leaking cup or seal. Fortunately I have a used spare which appears in good shape.
I’m off camping in a few days so wanted to crack on but didn’t have any crush washers for the brake line banjo at the M/c. At a pinch I will anneal the old washers but managed to get some for delivery tomorrow.
Three questions:
1) Does the team think my diagnosis is correct re leaky cups/seals, or should I look elsewhere in case my swap doesn’t work?
2) Could I have used a Dowty washer instead of the copper crush?
3) I also appear to have some minor blow back on the ‘newish’ bleed nipples. Is it ok to seal the nipple to caliper join with a little silicon grease?
Thanks folks. Very keen to get back into no UK lockdown life and get the bike out on a 2000 mile welcome back ride.
Noticed an intermittent loss of front brake pressure. Bled the brakes which seemed clear of air. During the process I noticed that operating the lever made a wet air sound at the m/c piston. No obvious leaks of fluid in the area but I sprayed contact cleaner over the join of M/c to twist grip housing which bubbled under pressure. Assume I have a leaking cup or seal. Fortunately I have a used spare which appears in good shape.
I’m off camping in a few days so wanted to crack on but didn’t have any crush washers for the brake line banjo at the M/c. At a pinch I will anneal the old washers but managed to get some for delivery tomorrow.
Three questions:
1) Does the team think my diagnosis is correct re leaky cups/seals, or should I look elsewhere in case my swap doesn’t work?
2) Could I have used a Dowty washer instead of the copper crush?
3) I also appear to have some minor blow back on the ‘newish’ bleed nipples. Is it ok to seal the nipple to caliper join with a little silicon grease?
Thanks folks. Very keen to get back into no UK lockdown life and get the bike out on a 2000 mile welcome back ride.
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