Leaking Brake Fluid

[Derramax]

I went to move m my wife's 15 Golf and the clutch pedal went and stayed on the floor. The Reservoir was low on fluid. I took out the airbox and battery to look for leaks in the clutch system and bleed it back to function. Got it back working and couldn't find any leaks in any of the clutch hydraulics and it was dry inside car. I suppose my next step is to check the brakes and lines at each wheel, one by one.
Question I have is: Anything else I should check to find where I am losing brake fluid? I'm going to monitor the fluid level to see just how fast the amount is going down in the reservoir and see if I have a slow leak or a significant one.

Thanks

 

[oilhammer]

Slave cylinder... .small leak inside the bellhouse. Time to take the transmission out. It happens. The 6sp's curse, I suppose (the 5sp slaves are easily replaced from outside, but those hardly ever fail, go figure).

 

[Derramax]

Slave cylinder... .small leak inside the bellhouse. Time to take the transmission out. It happens. The 6sp's curse, I suppose (the 5sp slaves are easily replaced from outside, but those hardly ever fail, go figure).

Anyway to confirm this before taking on the job?

 

[oilhammer]

Sometimes there is a tiny bit seeping out the bottom of the bellhousing before it gets really bad. If it isn't already.

 

[Derramax]

So if I remove the belly pan I should see something at the bottom of the bell?

 

[oilhammer]

I don't know... if you do, you do, if you don't, you don't... and you can wait until/if the fluid/clutch drops again. I'm just trying to say that this is a common thing, it happens. It takes very little fluid (volume) to cause a loss of hydraulic pressure to the clutch slave.... like, a couple tablespoons worth. If you spread a couple table spoons worth of fluid INSIDE the bellhouse and mix it with some normal brake dust, it might not be that evident that it is leaking from the outside, but once the transmission is out the muddy paste it left inside will be obvious.

 

[Derramax]

I don't know... if you do, you do, if you don't, you don't... and you can wait until/if the fluid/clutch drops again. I'm just trying to say that this is a common thing, it happens. It takes very little fluid (volume) to cause a loss of hydraulic pressure to the clutch slave.... like, a couple tablespoons worth. If you spread a couple table spoons worth of fluid INSIDE the bellhouse and mix it with some normal brake dust, it might not be that evident that it is leaking from the outside, but once the transmission is out the muddy paste it left inside will be obvious.

I see what you mean. Will fluid leaking in the bellhousing have any effect on the clutch and cause that need to be replaced? Maybe not like a leaking rear main but I don't know.

 

[Derramax]

Thanks for the help oilhammer. I'd love to tackle this job myself but with out a lift and a month of free sundays looks like I'm going to have to have a shop handle it. Used to be a really good TDI only mechanic here but he moved away during the pandemic.

 

[oilhammer]

Typically slave cylinder leaks just seep down the inside wall of the bellhouse and don't really find their way on to the clutch or flywheel. It would have to be leaking pretty bad for that.

 

[RIP TDI]

Some Euro TDI models, including the GTD, use a Sachs clutch set rather than the LUK set used in our NA market TDIs. One difference between them is the slave cylinder/throwout bearing for the Sachs setup uses a different seal arrangement than the LUK and is not vulnerable to the leakage common for the LUK slave/TOB. Unfortunately, the slave/TOBs are proprietary and not interchangeable, but If for any reason the clutch and DMF also need to be replaced at this time, a conversion to a Sachs setup would be worth considering.

 

[Derramax]

Some Euro TDI models, including the GTD, use a Sachs clutch set rather than the LUK set used in our NA market TDIs. One difference between them is the slave cylinder/throwout bearing for the Sachs setup uses a different seal arrangement than the LUK and is not vulnerable to the leakage common for the LUK slave/TOB. Unfortunately, the slave/TOBs are proprietary and not interchangeable, but If for any reason the clutch and DMF also need to be replaced at this time, a conversion to a Sachs setup would be worth considering.

Good to know, thank you

 

[Derramax]

Took the Golf to the shop. They say I need a clutch kit and can save money if I supply the parts. Anyone know of a good vendor to get the euro Sachs kit?

 

[RIP TDI]

Took the Golf to the shop. They say I need a clutch kit and can save money if I supply the parts. Anyone know of a good vendor to get the euro Sachs kit?

FCP Euro has kits in 2-part form (plate/disc/TOB + DMF), I think. Darkside Developments in the U.K. is often mentioned here, has a larger selection and all-in-one kits. BTW, if you are planning to add a tune or other torgue-increasing mods at some point, Sachs has an SRE performance clutch, although the weak link in a clutch upgrade is the DMF; there is no performance aftermarket DMF and the OE DMF will shudder within a certain RPM range with a sizeable torque increase.

The Darkside selection is huge; hopefully member adjat84th will chime in here with a recommendation; he has deep knowledge on this subject.
Darkside Developments clutch sets

 

[Derramax]

Sachs 1.6 (Quattro) / 2.0 TDi 6 Speed Dual Mass Flywheel and Clutch Kit

Fits VW / Audi / Seat and Skoda 1.6 TDI (Quattro / 4Motion) & 2.0 TDI 6 Speed Vehicles

www.darksidedevelopments.co.uk

 

[RIP TDI]

FCP Euro kit w/o DMF.
FCP Euro DMF.
Free shipping from Connecticut.

While you're at it, you might want to either remove the delay valve from the bleeder block or replace the OEM plastic block with an ECS Tuning aluminum block.

 

[Derramax]

I've seen the aluminum block from ECS. What world that upgrade do?

 

[RIP TDI]

I've seen the aluminum block from ECS. What world that upgrade do?

Removing the delay valve or replacing with the ECS block eliminates the slight buffering of clutch release which is supposed to help novice clutch users achieve smooth engagements, but for experienced folks who are used to a quick AND smooth release it can cause inconsistent release action and sometimes stalling. The reviews of this mod that I've read are overwhelming positive.

 

[oilhammer]

You can also ditch or dial back the hill holder in the ABS, another nanny thing that experienced drivers don't need or like.

 

[pedroYUL]

Sachs 1.6 (Quattro) / 2.0 TDi 6 Speed Dual Mass Flywheel and Clutch Kit

Fits VW / Audi / Seat and Skoda 1.6 TDI (Quattro / 4Motion) & 2.0 TDI 6 Speed Vehicles

www.darksidedevelopments.co.uk

That's an amazing price for a kit. I will bookmark that for my own!

I have ordered a couple of things from Darkside, they ship extremely fast and very reasonably

 

[turbobrick240]

The LUK rep set kits with disc, p-plate, and throw out/slave are like $300. Most people seem to get good service life from the LUK setup.

 

[pedroYUL]

Yeah, but we all know every DMF needs replacing at some point

 

[740GLE]

which would you rather replace DMF or synchro's?

As for big power with tuning and shuddering with DMF, you can tune away from the shudder, sure you're not getting full output possible but much better than stock.

 

[turbobrick240]

which would you rather replace DMF or synchro's?

As for big power with tuning and shuddering with DMF, you can tune away from the shudder, sure you're not getting full output possible but much better than stock.

Neither if they don't require replacement. I think it's safe to assume we're talking about a stock vehicle here. If it were mine, I'd probably want to replace the dmf if it had over 100k miles on it while it's apart. Otherwise, I'd save some money and toss a $275 LUK rep set kit on.

 

[pedroYUL]

Exactly, neither, I don't replace but confirmed failed parts.

Both my 2015 6MT cars are beyond 100k miles, and imo in stock cars when the clutch starts slipping, the DMF is not far behind to start rattling...if you know how to drive a stick

 

[turbobrick240]

Yup, maybe the OP will chime in with info on his cars mileage. Doesn't sound as though he's experiencing any slippage.

 

[pedroYUL]

Sachs 2.0 TDi 6 Speed 02Q Dual Mass Flywheel and Clutch Kit

Sachs 2.0 TDi Dual Mass Flywheel and Clutch Kit for 02Q 6 Speed Gearboxes

www.darksidedevelopments.co.uk

Now that's a steal

 

[RIP TDI]

Sachs 2.0 TDi 6 Speed 02Q Dual Mass Flywheel and Clutch Kit

Sachs 2.0 TDi Dual Mass Flywheel and Clutch Kit for 02Q 6 Speed Gearboxes

www.darksidedevelopments.co.uk

Now that's a steal

I wonder if this is intended for a 110hp MK6 application? That might explain the price delta to the Sachs kit listed above that specifies a 150 MK7 application.

 

[pedroYUL]

I wonder if this is intended for a 110hp MK6 application? That might explain the price delta to the Sachs kit listed above that specifies a 150 MK7 application.

There's an Audi CR170 in the application's list

 

[RIP TDI]

There's an Audi CR170 in the application's list

I ran the DMF & clutch OE p/ns for both kits against the online VW catalog and the $650 kit crossed with 2015 CRs vs. 2008-2014 PDs & CRs for the $450 kit. I was a little concerned that Darkside titled the $650 kit as 1.6 (Quattro)/2.0..., but with the listed CRUA application and components that cross correctly with the VW catalog, I feel confident that this is what Sachs deems as correct for a Mk7.

I've never worn out a clutch in 50 years, but when my LUK CSC springs a leak , this is the kit I will use. I don't want to take a chance that there might be some fitment or DMF tuning issue with the other kit and $650 still sounds pretty reasonable to me.

 

[turbobrick240]

That $650 is probably closer to $850 with VAT and shipping from the UK priced in