Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Clutch fluid

Another newbie question What fluid should I use to top off the clutch and brake fluid reservoirs on my 1980 + 8 ?

I'd go for DOT4 Fluid

+1

Just to be sure draw off a small amount of fluid and put into a container with 1/2 " of water. If the two mix it is Dot 3, 4 or 5.1 glycol based (all will mix together). If the water and fluid don't mix it will be silicone based Dot5 (and will not mix with the other fluids).

If glycol I, too, would go for dot4 and here's a useful link..........https://blog.amsoil.com/dot-3-and-dot-4-brake-fluid-whats-the-difference/

It is far better to go for the cheaper lower boiling DoT 4 fluid and change it more regularly than leaving the the higher boiling glycol based DoT 5.1 in for longer.

Unless you are racing (or driving down the side of a mountain continuously?) DoT 4 is more than sufficient for our needs. Morgans are light cars, have generously sized brakes so do not generate excessive heat into the fluid

If you have not already visited GoMog I would bookmark the site as a great deal of information is contained in the pages:

https://www.gomog.com/allmorgan/allmorgan.html

Quite good for the older generation cars (pre 2003) but I have noticed that some of that is need of updating tbh and some information needs treating with caution.

It's a good starting point before you pose the questions on TM in particular for the later traditional cars.
There was nothing on there for my 2009 4/4 Sport but a wealth of hands on accurate knowledge here.

OK I did the mix test and the fluid forms globules on top of the water.

So which fluid should I go with ? I noticed some of the fluids are synthetic.

And yes I've got GoMog bookmarked.

Thanks !

My mid 80`s +8 was subjected to a nut and bolt rebuild circa Y2K and at the time Automec SBF DOT 5 brake & clutch fluid was used.

Aprently this fluid was developed for/by the US military for use in their vehicles.. ?

I have owned my +8 since 2002 though only driven circa 28k miles in that time in the heat of the Med in mid summer and occasionally in the snow of Wintertime Scotland ... I have neither changed or topped up my clutch fluid..

A year or so back I replaced the brake fluid having stripped the front calipers to replace holed rubber dust covers and decided to remove the pistons while at it. No corrosion in the bores or pistons other than in areas exposed to weather as the result of the holed dust covers. There was no need to strip the rear wheel cylinders as they were free clean and fluid tight thus operating perfectly..

I like the idea of non-hydroscopic brake fluid, it has worked so far for me.

Your results may vary..?

Dutch,

Here’s a vid confirming the test. Though it adds water to fluid the chemistry is the same. But, you may see results more clearly.
https://www.youtube.com/watch?v=0aMf3I0ez5s&t=15s

At present it suspiciously looks like you may have Dot 5.

If any doubt and because of the seriousness of messing with brakes may I most respectfully suggest you take the test results to a brake shop for a second opinion.

Let us know how you get on.