Clutch Fluid

[neill1607]

The cap on my '88 clutch master cylinder says Dot3 only.

Should I use Dot 3? or have others used a different fluid?

[S4Esprit]

The cap on my '88 clutch master cylinder says Dot3 only.

Should I use Dot 3? or have others used a different fluid?

Stick with the Dot 3. I used synthetic and it leaked almost immediately. Replaced the synthetic, problem went away.

[fjmuurling]

Hello Neill,

You can use DOT 4 and DOT 5.1 instead of the DOT3 fluid. They are of a higher spec. I would recommend a DOT 4 as the DOT 5.1 is generally of a lower viscocity (thinner). DO NOT USE DOT 5 (without the .1) as this is a completely different fluid (silicone based) and will eat your seals. One last point, when changing your fluid make sure everything is clean and be very carefull not to spill anything because the fluids are a great paint remover, in case of a spillage clean with copious amounts of water.

Freek

[neill1607]

If I'm topping up the existing fluid, is it ok to mix them?

I don't know what's in there at the moment!

[andydclements]

Fine to mix DOT4 with DOT3 and DOT5.1.

Just don't mix silicone & mineral.

Keep in mind the spec will probably be part way between those of the mixed fluids.

[Tentenths]

It is generally recommended that the fluid should be replaced every 2 - 3 years anyway. So, unless you know yours has been done fairly recently, I'd be inclined to flush out & replace. Oh, and if the old fluid comes out the colour of black ink it's time to replace the cylinder seals.

[neill1607]

The master cylinder is leaking which is why I need to top it up.

Just ordering a new one along with a slave cylinder & a braided hose to replace the red one, once I've got those, should be better than new.

The leaking fluid has settled in a dip under the master cylinder beside where the red hose goes down. As everyone knows the fluid doesn't like paint and has made a bit of a mess. I've mopped up as much as I can, but will it have done any harm to the fibreglass? Is there anything that is good at soaking up the fluid? If fluid is spilt most things I've read suggest lots of water to rinse the area free but I can't do that in this case as the fuses/relays are right beside there and the "bonnet" would (i guess) fill up with water as well!

[Glyn Harper]

Red hose? You need to swap that for a stainless one immediately.

I'll bet your clutch is hard to engage on hot days?

[fjmuurling]

Neill,

use rags and change/rinse them regularly you don't have to fill the "bonnet" with water. I suggest to drain the system in order to prevent further leakage as you are awaiting new parts.

Freek