2nd fault in as many days...

[100K+]

I apologise for making another update but when I opened up the master cylinder today I was shocked by what I found.
In the bottom of the chamber by the outlet is just over 1 gram of white gritty material. How did this material get into what is supposedly a closed and sealed system, and what is it??
Anyone with any ideas please come forward, as the clock might be ticking for us all. A cylinder flush would not have removed this gunk either, as I needed a screwdriver to break it up to remove it. There are other deposits mixed with clutch fluid on all other surfaces too.

Cheers
Bob

[Kev0607]

Was the brake fluid changed at all in your ownership, or was it mucky/dirty looking? It can crystalize/feel gritty when it gets very old.

The brake fluid/clutch fluid reservoir is the primary entry point for moisture in the braking system. Brake fluid is Hygroscopic, which means it has a tendency to absorb moisture from the surrounding air over time. This moisture can enter the system through the reservoir cap or through microscopic pores in the rubber hoses that connect the reservoir to the brake components. As moisture accumulates in the brake fluid, it can lead to a decrease in the fluid's effectiveness and potentially cause corrosion within the system.

Its not actually a sealed system. It appears so, but it really isn't.

[100K+]

Originally Posted by Kev0607

Was the brake fluid changed at all in your ownership, or was it mucky/dirty looking? It can crystalize/feel gritty when it gets very old.

The brake fluid/clutch fluid reservoir is the primary entry point for moisture in the braking system. Brake fluid is Hygroscopic, which means it has a tendency to absorb moisture from the surrounding air over time. This moisture can enter the system through the reservoir cap or through microscopic pores in the rubber hoses that connect the reservoir to the brake components. As moisture accumulates in the brake fluid, it can lead to a decrease in the fluid's effectiveness and potentially cause corrosion within the system.

Its not actually a sealed system. It appears so, but it really isn't.

In 50 years of motoring I can't recall ever changing brake fluid. If a pipe failed a MOT I had to bleed the system, but back in the day Mini, Imps and Maxi's all had paper thin pipes that barely lasted. Additionally when you were forced to slacken bleed nipples, they always snapped, and I ended up chasing the brake lines back to the master cylinder!. Volvo stuff just appears to last - never had to change a pipe, therefore never bleed or changed the fluid - hindsight wrong decision - consider myself rightfully chastised...

Cheers Bob

[Kev0607]

Originally Posted by 100K+

In 50 years of motoring I can't recall ever changing brake fluid. If a pipe failed a MOT I had to bleed the system, but back in the day Mini, Imps and Maxi's all had paper thin pipes that barely lasted. Additionally when you were forced to slacken bleed nipples, they always snapped, and I ended up chasing the brake lines back to the master cylinder!. Volvo stuff just appears to last - never had to change a pipe, therefore never bleed or changed the fluid - hindsight wrong decision - consider myself rightfully chastised...

Cheers Bob

Cars of that age didn't have things like traction control and ABS. Traction control and ABS, although brilliant features, assist in raising the temperature of the fluid more. Its those raised temperatures over time, as well as the fluid absorbing moisture, that breaks it down. Plus the Volvo is a lot heavier than a Mini... the weight of the car puts more pressure on the brake components, as well as the brake fluid.

If you ever had a car serviced at a dealership (a modern one), at some point in time, they may have asked if you wanted the brake fluid changing. Some manufacturers have a brake fluid change as part of the service schedule, so it gets done anyway as part of the service. However, some manufacturers have the brake fluid change as an extra "add on" every few years, which you can either agree to or disagree. Many disagree, as it just adds to an already expensive bill. Brake fluid is often overlooked.

Its definitely something to consider in future... Check the brake fluid to make sure its in good condition, as well as the level. You can buy brake fluid testing pens, which show you the level of moisture via lights (green being good, orange meaning its okay, but not great and red meaning its bad). Or, just look at the colour of the fluid in reservoir. It should be more or less the same colour as it comes out of the bottle you buy to top up. If the fluid in the reservoir is dark brown or even black, it needs changing ASAP.