Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing

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Wed 29 May 2024 20:00
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - phil_z70

Hi everyone, longtime reader occasional poster here.

My neighbour has a ford focus 1.5 tdci 2015 with approx 50'000 miles on it, It has started loosing brake fluid, not loads, possibly needs topping up by 100ml twice a week. There are no visable leaks from any calipers, brake hose or drums. Overnight nothing drips onto the alloys and it doesn't leave damp patched on the drive. The brakes feel fine too.

It had a clutch done around 9 month ago and it's likely to have had a full kit fitted with slave cylinder (I don't have full info as it wasn't done at a garage), I haven't had time to take the undertrays off to make sure the bellhousing is dry but from what i can see from above it looks dry in that area. I will do this at the weekend.

Any ideas if it's not the clutch at fault ?

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Wed 29 May 2024 20:23
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - elekie&a/c doctor
I would take a look up by the pedals . Any evidence of hydraulic fluid up there ? If not , then the engine bay undertray will need to come down.
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Wed 29 May 2024 21:15
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - phil_z70

Thanks Doc, I will have a look tomorrow evening

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Thu 30 May 2024 01:05
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - edlithgow

If this has a "traditional" vacuum operated servo on the brakes (I dunno much about newish cars but I understand they quite often have separate pumps these days) its possible for a leak there to cause brake fluid to be ingested by the engine and burned.

This could mean loss of brake fluid which wouldn't show up as an external leak.

Only really damaging if you use silicone-based brake fluid (which puts synthetic sand in your engine), and it doesn't sound as if you've definitively excluded a leak, but perhaps worth bearing in mind as a possibility.

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Thu 30 May 2024 11:26
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - galileo

If this has a "traditional" vacuum operated servo on the brakes (I dunno much about newish cars but I understand they quite often have separate pumps these days) its possible for a leak there to cause brake fluid to be ingested by the engine and burned.

This could mean loss of brake fluid which wouldn't show up as an external leak.

Only really damaging if you use silicone-based brake fluid (which puts synthetic sand in your engine), and it doesn't sound as if you've definitively excluded a leak, but perhaps worth bearing in mind as a possibility.

I think this is a diesel, so will need a separate vacuum pump.

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Thu 30 May 2024 12:37
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - elekie&a/c doctor
Diesel or petrol both have regular vacuum servo , but yes , diesel will have engine driven pump .
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Thu 30 May 2024 19:20
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - phil_z70

Hi

I have had a check inside the car and the leak is coming from above the clutch pedal which will be the clutch master cylinder (I think), Does anyone know if it's a really difficult item to change due to the limited access in the engine bay, plus is it easy to bleed the clutch when changed ?

Edited by phil_z70 on 30/05/2024 at 19:27

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Thu 30 May 2024 20:07
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - elekie&a/c doctor
This is no easy job . Steering column needs to be released from the rack and the clutch pedal box unbolted from the bulkhead. Also the wiper scuttle panel needs removing for pipe access . Bleeding the system shouldn’t be a problem from the gearbox end .
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Thu 30 May 2024 20:51
Ford Focus 2015 1.5 tdc - Ford Focus 2015 1.5 tdci brake fluid disappearing - phil_z70

Thanks for your help Doc, not a job i'd want to take on, I'll get her to take it in to a garage

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