Technical Two brake fluid reservoirs ?

[GC157]

Hi all.
When i was checking the brake fluid on my wife’s 2007 panda 100 Hp , i noticed for the first time a second very small reservoir on the drivers side ? This is marked brake fluid ,but says fill with Dot 3. ? The main reservoir says Dot 4 . I'm just wondering what this is for and why it says to use different fluid to the main reservoir?

 

[dagdromer]

I assume that this is for the clutch. it seems that the 100hp right hand drive has a hydraulic clutch and it needs fluid. the left hand drive versions are using a cable or the reservoir from the brakes.

 

[Pugglt Auld Jock]

My 2010 Panda 1.2 60hp has this little reservoir which is the reservoir for the clutch system. As far as I've always understood the fluids are very similar, both being Glycol based, and neither will damage a system designed to use them (ie putting dot 4 in a dot 3 recommended system won't damage seals etc) however Dot 4 has a higher boiling point than Dot 3 and I haven't seen Dot 3 on my factor's shelves in a long time. I just top up with Dot 4 and it's been fine. There's now even Dot 4 plus which I believe has an even higher boiling point and is recommended for use in systems with hill hold and other "enhanced" braking features? I see it's seems to be recommended for my, newish, Ibiza but so far I've not had to top it up. I believe the Dot 4 plus is quite a bit more pricey. I wouldn't be filling up with Dot 3 where Dot 4 is recommended though.

 

[DaveMcT]

The clutch uses normal brake fluid. Not ideal because it absorbs water. Ideally extract old fluid with syringe and top up. Then bleed the lines to remove the old fluid. The battery box gets in the way, but it's easy enough to remove and you get chance to treat the inevitable rust. You also get chance to check the slave cylinder for any leaks.

 

[chris3234]

My 2010 Panda 1.2 60hp has this little reservoir which is the reservoir for the clutch system. As far as I've always understood the fluids are very similar, both being Glycol based, and neither will damage a system designed to use them (ie putting dot 4 in a dot 3 recommended system won't damage seals etc) however Dot 4 has a higher boiling point than Dot 3 and I haven't seen Dot 3 on my factor's shelves in a long time. I just top up with Dot 4 and it's been fine. There's now even Dot 4 plus which I believe has an even higher boiling point and is recommended for use in systems with hill hold and other "enhanced" braking features? I see it's seems to be recommended for my, newish, Ibiza but so far I've not had to top it up. I believe the Dot 4 plus is quite a bit more pricey. I wouldn't be filling up with Dot 3 where Dot 4 is recommended though.

I've also seen dot 4 abs although I doubt there any meaningful difference between them

 

[koalar]

pretty much all coved above

I would add the fiats owners manual is pretty good

if you don't have one, you can normally find a PDF format to download

 

[GC157]

The clutch uses normal brake fluid. Not ideal because it absorbs water. Ideally extract old fluid with syringe and top up. Then bleed the lines to remove the old fluid. The battery box gets in the way, but it's easy enough to remove and you get chance to treat the inevitable rust. You also get chance to check the slave cylinder for any leaks.

The clutch uses normal brake fluid. Not ideal because it absorbs water. Ideally extract old fluid with syringe and top up. Then bleed the lines to remove the old fluid. The battery box gets in the way, but it's easy enough to remove and you get chance to treat the inevitable rust. You also get chance to check the slave cylinder for any leaks.

 

[GC157]

It does look brown and gloopy in there.
To be honest, i’m just looking at basic fix to see if it goes through the mot first . is it ok to syringe it out and top up for now . the main reservoir colour looks ok .

 

[koalar]

It does look brown and gloopy in there.
To be honest, i’m just looking at basic fix to see if it goes through the mot first . is it ok to syringe it out and top up for now . the main reservoir colour looks ok .

yes

its what you are suppose to do before you bleed the system to stop as much rubbish as possible from entering the rest of the system

 

[DaveMcT]

There is little point in syringing the fluid from the reservoir without bleeding the far more damaging stuff from the system.

The battery box is easy to remove (13mm AF bolts) and some wiring clips.
Bleed screw on clutch uses an allen key. Just make sure you can open the screw if not you will need to replace the reservoir as they can rust solid.
(1) Syringe old fluid out of the reservoir and fill to near the brim with new brake fluid. Also, fit a clear tube to the slave cylinder drain snout so you can see what's coming out.
(2) Open slave cylinder bleed screw. Press the clutch pedal down. You can use a stick and it will stay down.
(3) Close the bleed screw and lift the clutch pedal slowly. Check reservoir level and top up when it gets below minimum.
(4) Repeat until the fluid coming out is clean with no bubbles.
(5) Lift clutch pedal and test for function. It should now feel the same as normal.
(7) Wash down the gearbox with a degreaser to clean away spilled brake fluid. Ditto the car firewall if you spilled any when topping up.
(8) Reassemble the battery box, etc and get on with your day.
(8.1) Derust the battery box for that added feel good factor.

Tips use an absorbent rag under the fluid reservoir to catch drips. When done, don't fill beyond the "max" line because the rubber bellows will push out any excess.

 

[chris3234]

There is little point in syringing the fluid from the reservoir without bleeding the far more damaging stuff from the system.

The battery box is easy to remove (13mm AF bolts) and some wiring clips.
Bleed screw on clutch uses an allen key. Just make sure you can open the screw if not you will need to replace the reservoir as they can rust solid.
(1) Syringe old fluid out of the reservoir and fill to near the brim with new brake fluid. Also, fit a clear tube to the slave cylinder drain snout so you can see what's coming out.
(2) Open slave cylinder bleed screw. Press the clutch pedal down. You can use a stick and it will stay down.
(3) Close the bleed screw and lift the clutch pedal slowly. Check reservoir level and top up when it gets below minimum.
(4) Repeat until the fluid coming out is clean with no bubbles.
(5) Lift clutch pedal and test for function. It should now feel the same as normal.
(7) Wash down the gearbox with a degreaser to clean away spilled brake fluid. Ditto the car firewall if you spilled any when topping up.
(8) Reassemble the battery box, etc and get on with your day.
(8.1) Derust the battery box for that added feel good factor.

Tips use an absorbent rag under the fluid reservoir to catch drips. When done, don't fill beyond the "max" line because the rubber bellows will push out any excess.

And easyer way is to get a handheld vacuum bleeder to bleed to cutch no messing around pressing the pedal up and down and opening and closing the screw multiple times

 

[jrkitching]

+1 on extracting as much of the old fluid from the reservoir as you can before you start, A good quality handheld vacuum bleeder makes this job much easier. You can even bleed it with the battery box in situ, providing you don't mind working by feel. I've done this myself, using the tool in the link.

Be aware the capacity of the reservoir is only about 50ml, so be prepared to top it up frequently or you'll end up with air in the system.

There is so little fluid in the system that it quickly degrades and it's best to change it annually. The clutch hydraulics have a much harder life than the brake ones.

 

[dagdromer]

if you buy a syringe to get all the old liquid out of the cup you can also use that to bleed the slave. Just connect a piece of hose to the bleed nipple and the tip of the syringe. Make sure the syringe its plunger is completely in, open the bleed nipple and slowly pull the plunger out. This will suck all the liquid out of the line. close the bleed nipple before taking of the hose, empty the syringe and repeat till you see fresh liquid.
just make sure you buy a syringe that holds a decent amount of cc.

 

[DaveMcT]

Sucking fluid out of the slave cylinder is quick but all too easy to empty the small reservoir. Doing it my way only takes about 5 pedal push-downs (10 if you accidentally suck in air). Its not a large system and you can check the reservoir level as you walk by.

 

[dagdromer]

Your method is working fine but is a 2 person job or one person and a stick job. I'm not sure how well willing your partner is to get off the couch to sit in the cold car to push a clutch pedal, mine likes to stay inside. And the one person and a stick job is quite labor intensive. Open the bleed nipple, walk to the clutch pedal, push it in, mount the stick, walk to the slave cilinder, close the bleed nipple, walk to the clutch pedal, remove the stick, walk to the slave cilinder, open the bleed nipple and repeat that 5 times.

if you empty the reservoir with the syringe you know how many full syringes it takes to empty it. or when you have a big syringe how far the plunger can be extracted before you suck it dry. The lines and the cilinders do not hold that many fluid so if you take half of the amount you got out of the reservoir as a reference you will get old the old fluid out but never suck the reservoir dry.

 

[DaveMcT]

Brake bleeding needs two people, because the pedal comes straight back. You need a helper to keep it down.
The clutch behaves differently. When you open the bleed nipple the clutch pedal goes down and stays down. You don't need a helper. Just open the valve go around and push the pedal down. Walk back and close the bleed nipple, go back to the drivers side and slowly pull the pedal back up. Check the fluid level and repeat 5 to 10 times. Job done.

 

[koalar]

Brake bleeding needs two people, because the pedal comes straight back. You need a helper to keep it down.
The clutch behaves differently. When you open the bleed nipple the clutch pedal goes down and stays down. You don't need a helper. Just open the valve go around and push the pedal down. Walk back and close the bleed nipple, go back to the drivers side and slowly pull the pedal back up. Check the fluid level and repeat 5 to 10 times. Job done.

correct.

Although not not strictly needed as a last procedure I still normally get someone to push the pedal down and close the bleed screw while its still on the down stroke.

Just a bit of piece of mind that no small amount air can enter via the threads although infinity small there's always a small amount of back flow and suspect it will make no difference but its just the way I have always done it

I have thought about buying a vacuum bleeder mainly for brakes and other cars as last time I had to get a stranger walking down the street to help me

 

[dagdromer]

build one myself years back as I was without help and needed to get the brakes working. it needed to work only for that day but in fact it works so well that i kept it.

I used a glass jar with a steel lid, like the one's you find in the super market with beans or veggies in it. drilled a small hole in the lid and screwed in an old brass vacuum pipe connection from a carb. seal it with some gasket maker to make sure you still have vacuum. then I drilled a larger hole that would just fit the rubber part of a whine vacuum kit that normally goes into the bottle. again some gasket maker around it to be sure.
fit a clear hose on the vacuum pipe that goes to the bleed screw and that's it.

before opening the bleed screw make sure you already have some vacuum in the jar. open the screw and use the hand pump so now and then to keep vacuum in the jar. this will pull the fluid out of the bleed screw. Make sure you close the screw before al the vacuum is gone and you have an airless brake system.

 

[Pugglt Auld Jock]

build one myself years back as I was without help and needed to get the brakes working. it needed to work only for that day but in fact it works so well that i kept it.

I used a glass jar with a steel lid, like the one's you find in the super market with beans or veggies in it. drilled a small hole in the lid and screwed in an old brass vacuum pipe connection from a carb. seal it with some gasket maker to make sure you still have vacuum. then I drilled a larger hole that would just fit the rubber part of a whine vacuum kit that normally goes into the bottle. again some gasket maker around it to be sure.
fit a clear hose on the vacuum pipe that goes to the bleed screw and that's it.

before opening the bleed screw make sure you already have some vacuum in the jar. open the screw and use the hand pump so now and then to keep vacuum in the jar. this will pull the fluid out of the bleed screw. Make sure you close the screw before al the vacuum is gone and you have an airless brake system.

I too have thought about buying a vacuum bleeder. I've had a Gunson pressure bleeder for many years and it which works well when the adapter cap seals properly to the master cylinder reservoir but I've also had several memorable disasters when the cap has leaked and allowed fluid to leak! As the kit is aging and the rubber rings are getting harder I now don't use it very much - also, being an older version of the kit, there are not so many of the adapter caps which fit the modern master cylinders. What puts me off about the vacuum bleeders is that they seem to suck air in around the bleed nipple screw thread so you always see bubbles in the bleed tube. People do say this can be minimized by coating the bleed nipple threads with grease? I like to see an air free stream in that tube when I'm bleeding to reassure me that all air has been bled out..

I note that the 3 local garages, who I know well enough to be allowed to wander round their workshop, have "professional" grade pressure bleeders, not vacuum. If I can make a vacuum bleeder work for me I particularly like the idea of also being able to use it for diagnosing the likes of MAP sensors etc.

I'm very interested to hear about your home made one, I really enjoy trying to make this sort of thing, however I've never heard of a "whine vacuum kit"? I'm wondering if you mean a "Wine Vacuum Kit" ? but even so I've never heard of that either! I'd love to see a picture of your setup if you can manage to post one.
Kindest regards
Jock

 

[dagdromer]

again lost in translation, but the wine vacuum pump is nothing more than this: https://www.bol.com/nl/nl/p/vacu-vi...MI3LjKxMW99QIVTed3Ch2oLwGuEAQYASABEgJB4fD_BwE