Alternative to mineral oil

[jack smith]

my tektro hydro brakes are missing some fluid in the res. is there something else i can use to top it up at home? I need the bike for a trip to the trail centre thisweek and cant get any proper stuff in time. Something that wont kill the seals.

 

[Yellow Saddle]

No, mineral oil is all you can put in there. And, not the mineral oil you get from the chemist, that's something completely different.

Citroen, Audi and Rolls Royce cars use the same type of mineral oil in their power steering systems. It is branded as Castrol LM. If you have access to that, otherwise, a bike shop is your first port of call.

 

[Cubist]

Halfords. If they haven't got any. Citroën auto transmission fluid is much the same thing as Yellosaddle says. And they sell it at Halfords.

 

[Yellow Saddle]

It is very unusual for a brake reservoir to have lost some fluid. Keep in mind that the fluid level rises and falls as the pads wear and are replaced. With old worn-down pads the reservoir level will be lower than with new pads - and quite a bit too. And then filling, try and fill with new pads on or at least, simulate the piston position as if it has new pads in, otherwise you won't be able to fit the wheel once you have changed pads.

 

[jack smith]

The issue is the level of fluid is below the hole where the fluid goes into the hose so when i pull on the lever it just sucks in air, they had been spongey for a while (possibly since i got the bike) , its a 2013 bike i got used so god knows whats happened to it beforehand, the front pads are stuck in place as the retaining screw just spins and wont unscrew even if pressure is applied to the opposite side. So ive a feeling the previous owner has had a tinker and not had a clue what he was doing.

 

[Yellow Saddle]

The issue is the level of fluid is below the hole where the fluid goes into the hose so when i pull on the lever it just sucks in air, they had been spongey for a while (possibly since i got the bike) , its a 2013 bike i got used so god knows whats happened to it beforehand, the front pads are stuck in place as the retaining screw just spins and wont unscrew even if pressure is applied to the opposite side. So ive a feeling the previous owner has had a tinker and not had a clue what he was doing.

The oil is so expensive that I would hesitate buying it just to see if it will work. I recommend you first see if you can fix the pad problem before worrying about the fluid. You may have to ditch the brakes.

 

[jack smith]

The local trail centre bike tech said it's common on tektro brakes and I just need to split the actual caliper and remove it with vice grips and insert a new screw, then re bleed, the back is the biggest issue anyway the front brake just needs abit of oil to top up where as the rear needs a fair bit

 

[Moodyman]

Where in the world are you?

If you 're in the Leeds and surrounding area you 're welcome to my Shimano mineral oil and syringe.

 

[jack smith]

Thanks for the offer but im in durham unfortunatley