F**KED DISA VALVE

[rookie975]

I could be wrong, but I though the flap moves freely in the M54 engine when it is out the engine ? I know the N52 one doesn't move freely, but they changed the design and I think made it motorised ?

What year did they change the design?

My M54 (on an Aug 05 plate) has a vacuumpump, so there is resistance on my pre facelift

That's correct, it does have a vacuum pump. I found mine moves freely so it is obviously shot.

This is the type of kit you'll need - check the model though

http://www.ebay.co.uk/itm/BMW-DISA-Valve-Intake-Adjuster-Unit-Aluminium-Repair-Kit-11617502275-/161027574098?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item257dfdc952

I offered £45 a couple of months back & was accepted, so maybe start at £40

That's the one I've ordered, it should be here on Monday hopefully.

Erm, I need one too! Scared shitless of this!

Get the kit ordered mate! The DISA is a piece of cake to remove, the overhaul process looks pretty straight forward as well looking at this guide.

 

[Jembo]

RJS-Z4 - know you're well handy with a spanner - If in an doubt, ask either me or Bing as we've both done ours & are nearby

 

[rookie975]

RJS-Z4 - know you're well handy with a spanner - If in an doubt, ask either me or Bing as we've both done ours & are nearby

I second that mate, I'll be more than happy to help!

 

[neilthomas]

RJS-Z4 - know you're well handy with a spanner - If in an doubt, ask either me or Bing as we've both done ours & are nearby

I second that mate, I'll be more than happy to help!

and me!!!

 

[Machine monkey]

Fook I need one or do I what the fook is a DISA valve???

In all seriousness I need to check mine how do I do that? I could search for a link but I am to tired some one tell me!!

 

[Bing]

Fook I need one or do I what the fook is a DISA valve???

In all seriousness I need to check mine how do I do that? I could search for a link but I am to tired some one tell me!!

Everything you need to know is in here -

http://www.z4-forum.com/forum/viewforum.php?f=30

I assume you can scroll and click

 

[Mark-Z4]

I could be wrong, but I though the flap moves freely in the M54 engine when it is out the engine ? I know the N52 one doesn't move freely, but they changed the design and I think made it motorised ?

What year did they change the design?

When they introduced the N52 engine - so on facelifts. I checked mine and it was obvious they'd improved it - pics and 'how to' of when I did it are in the engine how-to section

I was reading that last night, I'm going to take a look tomorrow evening

 

[rookie975]

I could be wrong, but I though the flap moves freely in the M54 engine when it is out the engine ? I know the N52 one doesn't move freely, but they changed the design and I think made it motorised ?

It shouldn't move mate, if it does then the Disa is knackered. There is a video here which shows a chap replacing a Disa valve on an M54. He shows the resistance the flap should have, there is a fair bit!

I have been looking into this and it appears there are two main problems with the Disa valve, and one is caused by the other.

The first problem is with the crank lever in the unit. This is the part that connects the flap to the vacuum pump in the unit and turns the flap (see the picture below). The second problem is linked to the first, this is the much more serious issue where the pin at the top of the unit can come loose and drop into the intake manifold

As you can see from the picture the crank lever has a clip at the bottom and directly above that a hex shaped section. The hex shaped connects to a matching female section in the flap and this allows the rotation of the bell crank lever to rotate the flap. What happens over time is the hex section rounds off as the materials are not up to the job. When this happens the flap stops turning (this is what has happened to mine). If the problem gets worse the flap can come very lose and this is when the pin at the top can work itself loose.

The kit on eBay replaces plastic crank lever with a new crank lever (aluminium apparently) and it replaces the pin with a long bolt making it impossible for it to come lose and drop into the intake manifold.

This doesn't look like a difficult job (I'll report back when I have installed the kit on mine) and for the sake of £50 it seems crazy not to do it!

 

[Nelly Welly]

Is this valve fitted to all six cylinder engines ?

 

[RJS-Z4]

I could be wrong, but I though the flap moves freely in the M54 engine when it is out the engine ? I know the N52 one doesn't move freely, but they changed the design and I think made it motorised ?

It shouldn't move mate, if it does then the Disa is knackered. There is a video here which shows a chap replacing a Disa valve on an M54. He shows the resistance the flap should have, there is a fair bit!

I have been looking into this and it appears there are two main problems with the Disa valve, and one is caused by the other.

The first problem is with the crank lever in the unit. This is the part that connects the flap to the vacuum pump in the unit and turns the flap (see the picture below). The second problem is linked to the first, this is the much more serious issue where the pin at the top of the unit can come loose and drop into the intake manifold

As you can see from the picture the crank lever has a clip at the bottom and directly above that a hex shaped section. The hex shaped connects to a matching female section in the flap and this allows the rotation of the bell crank lever to rotate the flap. What happens over time is the hex section rounds off as the materials are not up to the job. When this happens the flap stops turning (this is what has happened to mine). If the problem gets worse the flap can come very lose and this is when the pin at the top can work itself loose.

The kit on eBay replaces plastic crank lever with a new crank lever (aluminium apparently) and it replaces the pin with a long bolt making it impossible for it to come lose and drop into the intake manifold.

This doesn't look like a difficult job (I'll report back when I have installed the kit on mine) and for the sake of £50 it seems crazy not to do it!

Give me a shout when you're doing yours and I'll pop over? Can give you a hand and check the condition of mine?

 

[rookie975]

Give me a shout when you're doing yours and I'll pop over? Can give you a hand and check the condition of mine?

Of course mate, no problem at all. I'll hopefully be getting it on Monday, I'll give you a shout...

By the way, the bush replacement project is on hold for the minute (I'll explain when I see you), I'll probably look at doing that next Saturday or early next week if you're around?

 

[rookie975]

A quick update regarding my Disa valve.

As I stated earlier in this thread I checked my Disa valave as I was concerned about the pin being loose after reading neilthomas's post. The pin was secure on mine, but I noticed the flap was moving freely and independently of the vacuum pump/arm.

I ordered the kit from eBay seen here.

This arrived this morning, so I set about rebuilding my Disa following the instructions seen here.

I won't do a full write up as I'll only be repeating what is shown on the instructions. I can confirm the problem on my Disa valve was the bell crank lever. The hex section was rounded off so it was spinning around inside the flap connection and thus not working at all. The picture below is my bell crank lever

The stuff in the kit is of really good quality, and the bell crank replacement is MUCH sturdier. The design of the kit is also much better than the original as there is no way at all anything can fall off and drop into the inlet manifold. The installation was very straightforward and it took me no more than 30 minutes to compete.

This link is a short video to demonstrate my Disa valve operating as it should after the kit was fitted. It also confirms that the valve should not move freely when it is removed from the car, it should

For the sake of £50 it seems silly not to do it. It is certainly better to do this than spending £219.10 on a replacement unit that will have the same inherent faults.

I'll report back on the difference it makes to the running of the car when I've had a chance to take her out for a proper drive...

Happy fixing!

 

[Bing]

rookie975, great post

Really poor quality OEM part though, right ? Hardly looks worn at all :?

 

[rookie975]

rookie975, great post

Really poor quality OEM part though, right ? Hardly looks worn at all :?

Cheers Bing

Hehe trust me it's definitely worn, if you compare my bell crank lever to a new one there is a massive difference.

The above pictures show the extent of the wear. On the left is a new bell crank lever, you can see the hex section (circled) is quite defined and slightly narrower than the rounded section above. You can see the hex section on my old bell crank pictured on the right is nearly rounded off and a it is significantly narrower due to the wear. This wear meant the bell crank just turned inside the flap socket without moving the flap and rendering the Disa useless...

 

[Bing]

Yep, see it now

I am glad this whole subject got a sudden resurgence - seems there are a lot on the way out around the forum, and if they ever do let go the results are not ideal....

 

[rookie975]

I have had a good hoon in the car following this. I haven't really noticed a difference at idle, but there is a noticeable difference torque. The car seems to pull much more freely than before.

This may be a placebo effect, but even if it is I feel it was worth the effort to stop worrying about that damn pin falling out!

 

[rookie975]

I am glad this whole subject got a sudden resurgence - seems there are a lot on the way out around the forum, and if they ever do let go the results are not ideal....

Indeed Bing. I'm glad neilthomas created this thread, it gave me the incentive to get off my backside and get mine sorted out!

 

[RJS-Z4]

Great work mate, sorry I didn't reply to your message yesterday, been busy! We'll check mine over soon if that's OK

 

[GreyZed]

rookie975, great post

Really poor quality OEM part though, right ? Hardly looks worn at all :?

Cheers Bing

Hehe trust me it's definitely worn, if you compare my bell crank lever to a new one there is a massive difference.

The above pictures show the extent of the wear. On the left is a new bell crank lever, you can see the hex section (circled) is quite defined and slightly narrower than the rounded section above. You can see the hex section on my old bell crank pictured on the right is nearly rounded off and a it is significantly narrower due to the wear. This wear meant the bell crank just turned inside the flap socket without moving the flap and rendering the Disa useless...

Rookie it looks like you have used OEM plastic parts rather than the i6 Automotive aluminium upgrade kit, is there a reason for that? I did mine yesterday after reading this post and although my bell crank lever was in good nick (51k miles) the steel end pin came out far too easily for my liking. The thing I liked about the aluminium rebuild kit was that the pivot pin goes through the bell crank lever from the other side therefore removing the potential for anything to fall into the intake and have a fight with your valvegear or worse.

Shocking design really creating a scenario where something so small and cheap could cause so much damage (probably done by the same person that thought an electric roof motor would be OK sited in a drainage channel!).

 

[rookie975]

Rookie it looks like you have used OEM plastic parts rather than the i6 Automotive aluminium upgrade kit, is there a reason for that?

I did use the upgrade kit mate. The picture of the new crank lever above came from the interweb. I wanted to demonstrate the extent of the wear of my old lever compared to a new standard one.

You are quite right, the design of the upgrade kit is much better and it will prevent anything being able to fall off into the intake. It is worth doing the job for that reason alone