What does the (!) dash light mean?

[james-c]

The warning light next to the parking brake light, looks like (!), comes on intermittently. What does it mean and how do I make it go away?

 

[karl webster]

Breaks James. Check fluid level.

Could be be a faulty sensor maybe.

 

[pberrey]

I agree with Karl. If it's intermittent it's probably low brake fluid where the level is moving around under breaking etc. This also means your pads might be low.

Rgds


Sent from my iPhone using Tapatalk

 

[james-c]

Thanks that might be it - the break fluid is about half way between the min and max marks, which is triggering the warning light as the fluid sloshes around.

I was thinking the light meant something to do with the hand break...

 

[Chas]

I've found that the brake fluid only needs to be slightly low to trigger the warning light.

 

[Rob]

Your pads may be getting low as well, well worth checking.

 

[clivehorridge]

IMHO It will be the pad wear that's caused the fluid level to be low. Backing off the cylinders to insert the new pads will displace the fluid from the extended cylinders, back up into the master reservoir.

I advise not to top up the reservoir until you know it's necessary, after checking/changing the pads. Otherwise, when you come to change the pads, the master reservoir will overflow when you push the cylinders back.

 

[james-c]

Good point there Clive, I'll check the pads. Cheers

 

[Chris]

Typically when I push the pistons back, I stick the bleeder on and expel the manky old fluid out of the cylinders rather than squirt it back up the line. That way you get a gradual change of the fluid over time with all the muck and used fluid being removed.

 

[clivehorridge]

Typically when I push the pistons back, I stick the bleeder on and expel the manky old fluid out of the cylinders rather than squirt it back up the line. That way you get a gradual change of the fluid over time with all the muck and used fluid being removed.

Trust Chris to come up with the correct way to do it (and that's a compliment BTW Chris !).

I was being too hasty to stop James ending up with fluid cascading everywhere, whilst his head was jammed under the wheel-arch! I've already got that T- shirt, as with a few others, no doubt!

Brake fluid is nasty stuff in the wrong place and causes a big mess...

 

[james-c]

Clive I've got that T-shirt too and damaged paint work under the reservoir on the Volvo - not going to repeat that mistake again. Thanks for the tip on draining the brake fluid Chris.

I'm planning to replace the oil seals on the from axle in a few weeks time (not looking forward to the mess) - so I'll check the pads then. I want to do a proper job and repaint the axle, tie rods, wheel arches, etc too.

 

[frank rabbets]

You can use silicon brake fluid which does not damage paint work, is not hygroscopic and never needs changing. But it finds every little leak that you thought you never had.

 

[Towpack]

Dot 5 silicone based fluid is superior in just about every aspect. Used it a few times on bikes but it doesn't mix with the Dot 3/4 stuff so you'll need to buy enough to completely flush the system which could be prove expensive on the 80.

 

[uHu]

The dot-5.0 silicone not being hygroscopic is a problem. You will always get some moisture into the system, and as it is not absorbed, it stays at the bottom, at the wheels. There it boils when the brakes are used, and you get fading brakes; and it causes the pistons to rust from the inside.

Use dot-5.1, which is the best for general use, and mixable with 3 and 4.

 

[Towpack]

The dot-5.0 silicone not being hygroscopic is a problem. You will always get some moisture into the system, and as it is not absorbed, it stays at the bottom, at the wheels. There it boils when the brakes are used, and you get fading brakes; and it causes the pistons to rust from the inside.

Use dot-5.1, which is the best for general use, and mixable with 3 and 4.

Don't agree. Short of having a leak in the system which would be obvious due to fluid leakage, just how/where is water going to get in? The only way for water to get in is via an ill-fitting reservoir cap. Water vapour will obviously get in through the breather but will not be absorbed by the silicone Dot5 stuff. The problem of brake boil due to water in the system is just what the silicone fluid is designed to eliminate. JMO

 

[uHu]

Don't agree. Short of having a leak in the system which would be obvious due to fluid leakage, just how/where is water going to get in? The only way for water to get in is via an ill-fitting reservoir cap. Water vapour will obviously get in through the breather but will not be absorbed by the silicone Dot5 stuff. The problem of brake boil due to water in the system is just what the silicone fluid is designed to eliminate. JMO

http://www.gomog.com/allmorgan/brakefluids.html
http://importnut.net/brakefluid.htm
http://www.stoptech.com/technical-support/technical-white-papers/brake-fluid
Read.
Quoting StopTech: "DOT 5 is of little value to any conventional automotive or high performance application"

 

[james-c]

Also to note from the StopTech site:
"One last note on the DOT ratings: Systems designed for a particular type of fluid (especially prior to the wide distribution and use of DOT 4 fluids) should continue to be filled with that fluid. For example, in a car that was delivered with DOT 3 fluid, the internal components of the system (seals, brake hoses, and fittings for example) were specifically designed and tested for compatibility with the chemical composition of DOT 3 fluid. Because the DOT 4 grade fluid typically contains a different chemical composition, compatibility of system components may be an issue."

 

[frank rabbets]

I think the silicone fluid will only cause a problem if there is water already in the system or the water gets in somehow. I don't know if moisture in the atmosphere can condense in the reservoir. Water droplets may just lie in the bottom of the reservoir. I'll have to look at the design.

 

[Towpack]

I've used dot 5 in a few bikes in the past and also a 4x4 Sierra and experienced non of the drawbacks mentioned. The Sierra did have 4 new callipers fitted as the old ones were shot due to corrosion. With Dot 3/4, any water in the system will be absorbed in the fluid so the important point is to completely purge the system which will use much more of the new stuff than the systems fill capacity.

 

[frank rabbets]

I used silicone fluid back in the 70's when I used to rebuild cars and didn't want the nicely sandblasted and repainted callipers to suffer paint damage. I did not consider the seals as I thought that silicone fluid would be fairly inert. I also used cunifer bake pipes which are copper based and don't corrode.