E36 M3 Evo clutch hose pressure switch

[PeterGreen]

I recently purchased a braided clutch line kit for my E36 M3 Evo. I have it booked in today to be swapped over. Upon further inspection there appears to be a pressure switch on the old rubber hose, but no switch on the new braided one. Does anyone know if this switch is essential? The supplier of the hose says it's the right one & was unaware that there is a pressure switch on the original. I got the hose from;

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&am...

[dangerousbryan]

same one i got for mine mate.let us know how you get on because mine is getting fitted on friday hopefully along with a new clutch.

bryan

[PeterGreen]

Bryan, looks like it's definately the wrong hose for the Evo. The garage I took it to today said it's probably for the non-Evo, as the Evo definately needs the pressure switch...

So my question now is does anyone know where to source the correct hose from?

Edited to add; I have tried getting on to the e36coupe.com forums to do a search on this, but they won't activate my account.

I have also spoken to my local BMW Stealership who have a hose (with switch), part no. 95090000002, for £46.39, but they're not sure if it's a braided one or not.

Edited by PeterGreen on Tuesday 30th October 15:59

[Cliffv8]

http://[url=http://bmwfans.info/original/E36/Cou/M...[/url]

list both for my 3.0L #12 from 1994/05 and #23 just says Clutch pressure hose, I'll go see witch its got
edit: can't see it without getting under it and getting dark but I'd say by the looks of it you've got the wrong one unless the switch housing comes off the end somehow but not likely

Edited by Cliffv8 on Tuesday 30th October 16:33

[dangerousbryan]

i have just emailed the guy off ebay so will see what happens.

bryan

[dangerousbryan]

just had a reply and he says he has sold quite a few.so maybe theres a way of getting the old one out of the pressure switch and screwing the braided one in?

bryan

[PeterGreen]

dangerousbryan said:

just had a reply and he says he has sold quite a few.so maybe theres a way of getting the old one out of the pressure switch and screwing the braided one in?

bryan

The garage I took it to tried that, but it looks like the switch is bonded to the old hose.

[Mroad]

Get a T-piece to go on the end of your hose to the pressure switch, shouldn't be a major problem.
Does anyone know what the pressure switch is for anyway? I know my old Integrale had a clutch pedal switch to disengage the ABS in certain situations, is this a similar case?

[Dave Dax builder]

I couldn't be certain but I think what you are talking about is not a switch but a "Slow release valve" that doesn't allow the clutch fluid to exit the slave cylinder too quickly and helps the life of the clutch and gearbox by reducing the shock when releasing the clutch pedal quickly. If you want to go faster though I believe that some people just remove them anyway for faster clutch take up.
HTH.

[dangerousbryan]

can someone ask on e36coupe forum as my account hasn't been activated yet.
could do with knowing pretty quick as mine is getting a new clutch on friday and my braided clutch pipe has just turned up.
bryan

[Mroad]

Dave Dax builder said:

I couldn't be certain but I think what you are talking about is not a switch but a "Slow release valve" that doesn't allow the clutch fluid to exit the slave cylinder too quickly and helps the life of the clutch and gearbox by reducing the shock when releasing the clutch pedal quickly. If you want to go faster though I believe that some people just remove them anyway for faster clutch take up.
HTH.

I know what you are talking about (restriction valve) but it's not that, it's actually a switch. It's item 25 in the diagram above.

I would have a look at e36coupe for you but like yourself it seems to be easier to get into Fort Knox than to get approved. Three or four emails and three months of trying and I've given up, I've never had such a problem getting on a forum even ones with twice as many members.

[andygtt]

Hi Did we get an answer to this as I bought this hose as well and they guy says to just remove the switch?

I tried to register on the E36 forum in January but never got an activation so still can't get on it.

Surelly there is a long term solution to this as I want the car to become a track car now and the long clutch travel increases the gearchange time.... can we retro fit the std M3 master or clutch????

[uberGTV6]

I bought / fitted the braided hose kit from http://www.bmsport.com/ and it comes with a brass T piece that switch screws in to :-)

you should be able to buy one seperately from a good motor factors

Edited by uberGTV6 on Thursday 3rd July 13:27

[k60djg]

did mine at the weekend
got it from Bexley Motors
http://www.bmsport.com/e-shop4(2008).asp
35.10 plus about 7.00 for delivery
it comes with a brass union & the pressure switch just screws into this new brass union
you need to unscrew the brake pipe on top of the existing black block it can then be removed with the rubber hose
the brass union then can be pushed up into the rubber grommet & the brake pipe screwed back in place
its a crap job as you cant see very well & a small mirror & torch helps
when i went to blead the system the clutch pedle just sprung to the floor but after pulling it back up a few times & pushing to blead the fluid through it now workes fine
hope info is of use
Duncan

[DamoWfd]

ive also had the above problems..i bought a braided clutch line for my 96 evo from a main dealer and it was braided but found it impossable to fit to the standard pressure switch so had to conceed defeat but am i right in thinking that this uprated kit listed about with the t-piece iincluded will be the right way to go to get my clutch bite back up off the floor?

[puncturewound]

This exact same thing happened to me, including this seller from ebay, they are well aware that this line is incorrect. I returned the line to them and told them i wasnt happy with the item description and they should refund me immediatly to avoid negative feedback, eventually i got my money back after a bit of nagging and i got the correct line from Bexley motorsport, it was a direct fit and completely transformed my clutch, Best bit of kit ive fitted yet!

[unzippy]

Mroad said:

Does anyone know what the pressure switch is for anyway?

It works in conjunction with the gear recognition switch on the side of the gearbox. It tells the ECU when you’re in gear. Not which gear, just that you’re in a gear, and not in neutral. The ECU uses signals from these two switches to change between fuel/ignition maps. If it thinks you’re sitting at a junction in gear, and the clutch pressed down, it assumes you are about to pull away, and selects a good map for this. If it sees you out of gear, and the clutch released, it assumes you’re not going to suddenly take off, so selects a map that gives a smother idle, and possibly better emissions etc.

[naetype]

Can I ask where you got that information from? I've spent hours pouring over DME schematics and not once have I seen such an input.

[Zead]

unzippy said:

Mroad said:

Does anyone know what the pressure switch is for anyway?

It works in conjunction with the gear recognition switch on the side of the gearbox. It tells the ECU when you’re in gear. Not which gear, just that you’re in a gear, and not in neutral. The ECU uses signals from these two switches to change between fuel/ignition maps. If it thinks you’re sitting at a junction in gear, and the clutch pressed down, it assumes you are about to pull away, and selects a good map for this. If it sees you out of gear, and the clutch released, it assumes you’re not going to suddenly take off, so selects a map that gives a smother idle, and possibly better emissions etc.

This is correct. But there are a few different types of hoses kicking around. The one I was originally supplied for my M Coupe had the union for the pressure switch, but the car doesn't have the switch and the hose was too short to meet the other unions. Eventually swapped hose for the correct one. I think the only way you can be certain of the correct hose is to match chassis number against the parts listing. I don't think it's advisable to bypass the switch. Chances are if the hose doesn't come with the union, it's the wrong hose for your car if it has the switch.

Hope this helps, Z

[unzippy]

From my mate Ian H, he is my BMW oracle