hydraulic front brake not working after a lay up !

[sean brady scooters]

well this one just amazes me !
customer brought in a gp with front disc brake ..he has not used it for a while and the brake was not working ..no feel and no pressure ?
i suspected that the fluid must have leaked out over time but he assured me he had not ever noticed any leaks or puddles of fluid on the floor !
so i have just taken the top off the reservoir to find that it is full of a jelly like substance ...the fluid has obviously just turned into jelly !
never seen that before lol

[fairspares]

I heard about this before with a classic car and it was someone topping up with silicone based fliud which reacts with Dot4 , i believe its a complete strip and all components seals will need replacing.
Just done a google search and its saying a reaction of wrong type of fluids added, looks like quite a few people have done this before.

[sean brady scooters]

all sorted now ,but what a bit of a chew ...took me 4 hours !
next job on this scooter is the siezed up rear brake lol