General Clutch Reservoir rubber bung

[Davidporthcawl]

Silly question, sorry

when filling the clutch reservoir with fluid, do I fill to the Max level (or just under) then insert the rubber bung

or

should the fluid be to the max level with the bung in place ?

This is confusing me, any help is appreciated.

Cheers

 

[John202020]

Not sure of its purpose honestly other than to make reading the level harder? It may provide the airtight seal?

 

[jrkitching]

It may provide the airtight seal?

Basically that. The cap has to be vented; any air which comes into the reservoir will always contain some moisture and the rubber dam helps to prevent this moisture from getting into the fluid.

There's very little fluid in the system and even with the dam in place, it usually show signs of water contamination (by darkening) quite quickly. It should be changed at least as often as you change the brake fluid. Clutch hydraulic problems are often reported here and it pays to do what you can to minimise any risk of internal corrosion.

Fill the reservoir so that the level comes up to the max line once the dam is in situ.

 

[puntodeltathema]

It's a great question though. Personally I would fill to max and then stick the bung in. Assuming it doesn't overflow if you do that (don't think it does from memory).

I was taught by a venerable specialist that clutch hydraulics are best left alone if they are working - and especially if the fluid is dark as there's a good chance of moving muck around and causing a cylinder failure if you attempt to change the fluid....

Nick

 

[jrkitching]

Personally I would fill to max and then stick the bung in

Me too. From memory, it won't overflow if you do that.

I've often noticed quite a bit of condensed water on the top surface of the bung, so leaving it out is something I definitely don't recommend.

causing a cylinder failure if you attempt to change the fluid

One reason that happens is that if you bleed using the pedal pushing method, the piston is being pushed through a much longer stroke than in normal operation. On older cylinders, you can get a wear ridge at the limit of normal travel, and moving the piston past this point sometimes damages the seals.

Using a vacuum bleeder is safer; since there's no pedal movement, this can't happen. It's also a lot less messy.

It's also useful for getting most of the old fluid out of the master reservoir before you start.

All equally true when doing the brakes.

 

[puntodeltathema]

Yes vacuum is definitely my preference too. Partly because I once had a master reservoir explode using a pressure bleeder. To be fair it was a dubious aftermarket alloy item with a sight window - and the window gave way. The resulting damage to the paintwork from the ejected brake fluid somewhat spoilt the day......but a lesson was learnt.

 

[DaveMcT]

The brake pedal/master cylinder rarely moves full stroke. However the clutch almost always moves full stroke and gets used 10x as often as the brakes. Unsurprisingly the cylinders and seals get worn. Unless you "drop" the clutch pedal, the slave is always under pressure with the clutch pushing it back. Slaves wear of course but seals rarely leak and might hide a knackered cylinder. Wear in the master can cause air to get sucked past the seals. This gives that pedal to the floor effect.

Clutch fluid level should not fall as the clutch itself wears. It might actually rise. If the level is dropping you need to find the leak.

If the clutch is heavy and releasing near the top of pedal travel, you have a worn clutch. Eventually it wont release at all and you'll over stress the hydraulics.

If the clutch is not releasing properly or the pedal sticks down, you'll need to bleed the system. If the pedal improves you probably have worn master seals letting in air. New master cylinder required. It makes sense to replace the slave at the same time. Shop around carefully as some versions are silly money.

 

[Oz500]

The brake pedal/master cylinder rarely moves full stroke. However the clutch almost always moves full stroke and gets used 10x as often as the brakes. Unsurprisingly the cylinders and seals get worn. Unless you "drop" the clutch pedal, the slave is always under pressure with the clutch pushing it back. Slaves wear of course but seals rarely leak and might hide a knackered cylinder. Wear in the master can cause air to get sucked past the seals. This gives that pedal to the floor effect.

Clutch fluid level should not fall as the clutch itself wears. It might actually rise. If the level is dropping you need to find the leak.

If the clutch is heavy and releasing near the top of pedal travel, you have a worn clutch. Eventually it wont release at all and you'll over stress the hydraulics.

If the clutch is not releasing properly or the pedal sticks down, you'll need to bleed the system. If the pedal improves you probably have worn master seals letting in air. New master cylinder required. It makes sense to replace the slave at the same time. Shop around carefully as some versions are silly money.

I don’t suppose you have a parts number/list of what’s needed to be replace?
I’m having a crap time figuring out what to order when doing work on my 2008 500 Lounge…
I’m used to working on older Japanese motorcycles & being able to look at exploded parts diagrams, complete with part numbers & names in a list.

 

[DaveMcT]

Genuine Fiat clutch master comes complete with a pipe and QD coupling pre-filled with fluid. It's silly expensive and the QD coupling is usually seized solid. Search for Panda, 500 and Ford Ka. All use the same. Disconnect the pipe (hairpin clips at each end) and keep the existing pipe.

Searched eBay "Fiat 500 panda clutch master cylinder" found this.

CLUTCH MASTER CYLINDER 1587MM FITS FIAT 500 PANDA 11-14CNG 0903- | eBay

Find many great new & used options and get the best deals for CLUTCH MASTER CYLINDER 1587MM FITS FIAT 500 PANDA 11-14CNG 0903- at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

Searched eBay "Fiat 500 panda clutch slave cylinder" found this.

Clutch Slave Cylinder LuK 512 0021 10 For FIAT 500, IDEA, PANDA, PUNTO | eBay

Find many great new & used options and get the best deals for Clutch Slave Cylinder LuK 512 0021 10 For FIAT 500, IDEA, PANDA, PUNTO at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

 

[John202020]

This seller post to Australia note you can use the old pipe if OK
slave,
https://www.ebay.co.uk/itm/334794329308?fits=Car+Make:Fiat|Cars+Type:1.2|Plat_Gen:312_|Cars+Year:2009&epid=740441745&hash=item4df34c0cdc:g:icUAAOSwp-lkFAP6&amdata=enc:AQAIAAAA4AKd9MyELiNdSi1OPX3x0LqJxcmn0zI0RwrOGxShd63zjUTLEvElawwNqPhxyH2LagNhHMlFDIKsHIbWS/6E1oRvUeleLdrqKN6NLKYFgONWaPM2raHNJZwslmarTUbW/3EMB2+oOdQ2yawop9u9LVJhwquOjEhjiA63s6e9QtcbqDkvX6KdH09zaD3/sCkJk6QEBs31Y8DSX2CBMT8EyW/Hdwl27hMSuHn+8b+MB2MPhpsFKxI8Q2rPxbT2cVIpQdHpOJbxfZx3qZRYTxg0K/CUO7WcesZNtstLYqqF7wCJ|tkp:Bk9SR46Gh6f1YQ

Master also posts to Au note year when ordering

Clutch Master Cylinder fits FIAT 500 312 1.2 2007 on 169A4.000 B&B 55187040 New 5055936667310 | eBay

Find many great new & used options and get the best deals for Clutch Master Cylinder fits FIAT 500 312 1.2 2007 on 169A4.000 B&B 55187040 New at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

Here's an interesting item for us in the UK that suffers corrosion of the quick connect joint ?

Fiat 500 Ford KA Clutch Pipe Repair Slave Cylinder Master Cylinder Broken Joint 682328668195 | eBay

Find many great new & used options and get the best deals for Fiat 500 Ford KA Clutch Pipe Repair Slave Cylinder Master Cylinder Broken Joint at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

 

[The Panda Nut]

It's a great question though. Personally I would fill to max and then stick the bung in. Assuming it doesn't overflow if you do that (don't think it does from memory).

I was taught by a venerable specialist that clutch hydraulics are best left alone if they are working - and especially if the fluid is dark as there's a good chance of moving muck around and causing a cylinder failure if you attempt to change the fluid....

Nick

It will overflow. jrk is correct on this one

 

[puntodeltathema]

Sorry I meant the "MAX" mark, not "max" as in right to the top

 

[DaveMcT]

I wrap an old cotton rag around the reservoir and fill to the max mark. For bleeding, pump no more than five times before topping up. It sucks quite hard so don't let the fluid go any lower. When done, top up to the max line, insert the rubber widget and fit the cap. The rag will catch any overspill.

The peal sticks down so you can bleed the clutch on your own. Open bleed nipple, push pedal down, close bleed nipple, slowly pull pedal up. Repeat.