Disco 2 Steering Box leak - brake fluid as temp fix??

[Si Click]

Today I noticed fluid on the ball joint on the steering drop arm. I've yet to get under there and find the source, but I am assuming a slow seep from the output seal. I don't have access to a press to get the drop arm off, so will either take the box to a garage to pull apart or just bite the bullet and install a refurb unit on the grounds that a leak is probably an indicator of a failing box.
However, whilst searching the net to see if there was a way of replacing the seal without having to remove the box, I came across a number of suggestions that a slow leak could be fixed by adding a couple of capfulls of brake fluid to the PAS fluid. The idea being that the brake fluid would expand the rubber seal and stop a slow leak.
I'm not suggesting this as a solution when there is the opportunity to fix it properly in slow time, but could this is a viable temporary fix when travelling and away from suitable garage facilities? Has anyone tried it?

 

[kevstar]

Id heard this many years ago from old hackney drivers seemingly worked a treat, never tried it myself
chuck some in see if it works or get a tub with brake fluid & throw a couple of o rings in it see if they
swell up

 

[Si Click]

I'm not about to try it myself without understanding the potential consequences for everything else in the system. I don't want to have to replace the PAS pump because I burst the seals.

 

[sierrafery]

I can give a 5 star review myself to this https://www.ebay.co.uk/itm/LUCAS-OI...h=item1ed9d789be:g:sVMAAOSwZfJagukK:rk:2:pf:0 stopped a weak leak on mine and lasted about 2 years... i'd not put brake fluid in the PAS system whatsoever

 

[Lazydave]

I can give a 5 star review myself to this https://www.ebay.co.uk/itm/LUCAS-OI...h=item1ed9d789be:g:sVMAAOSwZfJagukK:rk:2:pf:0 stopped a weak leak on mine and lasted about 2 years... i'd not put brake fluid in the PAS system whatsoever

I used this aswell and it cured my leak.

 

[Si Click]

OK, I'll try some of that. Thanks

 

[Pawl]

My thought would be IF adding brake fluid to the steering fluid could cause swelling of the leaking rubber seal in the steering box, it's also likely to cause swelling of the rubber hose from the reservoir and worse, the seals in the ps pump - all of which could make the "leak cure" much more painful and expensive.
As a slightly related example, I've seen the results of incompatible oils added to the brake system and seals can actually end up twice as large, soft and very distorted - causing sealing failure way before they get that large.

 

[Si Click]

My thought would be IF adding brake fluid to the steering fluid could cause swelling of the leaking rubber seal in the steering box, it's also likely to cause swelling of the rubber hose from the reservoir and worse, the seals in the ps pump - all of which could make the "leak cure" much more painful and expensive.
As a slightly related example, I've seen the results of incompatible oils added to the brake system and seals can actually end up twice as large, soft and very distorted - causing sealing failure way before they get that large.

My concerns exactly. I'll give the Lucas product a try on the basis that it has been designed for the purpose and some experienced hands are endorsing it. My query about brake fluid specifically was whether this had any value as a "get you home" trick to have up your sleeve if you are overlanding and find yourself losing fluid a long way from home or help.

 

[sierrafery]

Brake fluid even if it was good it would have helped only for a minor leak like the dedicated stuff does as well so if such a minor leak occurs it's enough to top up the reservoir and drive it untill you fix it cos the fluid loss shouldn't be catastrophic... if you have a so serious leak to let you without fluid in let's say 100 miles no leak stopper would fix that.

 

[Si Click]

Thanks for the opinions everyone. The Lucas stuff arrived today and the instructions state that the contents should be added when the reservoir is at a low point. That makes sense except that my reservoir has not yet noticeably dropped and is still showing full. I did say this was a slow seep.
It will not be easy to find such a slow source until the weather improves, so my plan is to clean the fluid off the ball joint/drop arm and monitor for any new fluid or drop in reservoir contents. If there is definately a leak I will drain some fluid from the reservoir and add the contents of the bottle. I'll let you know if the leak (assuming there is one) stops.

 

[meego]

Thanks for the opinions everyone. The Lucas stuff arrived today and the instructions state that the contents should be added when the reservoir is at a low point. That makes sense except that my reservoir has not yet noticeably dropped and is still showing full. I did say this was a slow seep.
It will not be easy to find such a slow source until the weather improves, so my plan is to clean the fluid off the ball joint/drop arm and monitor for any new fluid or drop in reservoir contents. If there is definately a leak I will drain some fluid from the reservoir and add the contents of the bottle. I'll let you know if the leak (assuming there is one) stops.

I have used Lucas Leak Stop in the past for this very same issue. It might work short term, but the leak will return. So don't think this is a "Fix". The only fix is a new or reconditioned box. Even then, with a recon box the leak can return !! Nature of the beast I'm afraid.