Z4 Roof issue

[tekoo]

I am sorry I don't have answers to your questions.

These pump/motor units are only meant to be replaced not repaired so we don't have information about which side is responsible for what direction. You are the only one that maybe able to figure it out by following the pipes path to the hinges and trying to figure out the orientation and maybe guess the functionality/direction of movement induced by each pair of pipes in your specific scenario.

Otherwise we don't have any guides or documented troubleshooting for the pump itself.
There are no O-rings to the valves; only the screws and springs.

You can attempt my suggestions and any other you find elsewhere but if all fails you will need to replace the motor/pump unit because this is where the problem is.

[tekoo]

The only thing left ito try with this pump is taking it apart and cleaning everything inside with Alcohol (or CRC cleaner) and compressed air, including valves, nozzles and banjo bolts. Not sure if adjusting the screws of the valves will help but you can give it a try.

When you put everything back together you have to make sure the banjo bolts, copper spacers and line heads are installed correctly.The copper spacers are not all the same thickness (see diagram; ‘2’ is different size than ‘3’) and can throw off the essential perfect alignment so I wouldn’t just focus on evaluating if the spacers look new externally. If the copper spacers throws off the alignment on one banjo bolt, there will be a weak stream of fluid passing through that banjo bolt as the hole is partially obliterated by the misalignment with the circular head. This can simply result in the exact symptoms you are experiencing.
The slimmer copper spacer ‘2’ has to alway be the closest to the banjo bolt head (See diagram below). That’s why I said these are designed to be spacers more than washers!
313CC599-25A2-46BF-9D0B-5A23B4869711.jpeg

[tekoo]

When you see how small the bolt openings are you realize that any tiny deviation from perfect patency and alignment can easily block the hydraulic fluid flow.
565F9FBD-ADAE-4FF1-8FEB-A5AA680AF45A.jpg15417433-E27B-4950-AA3B-E42AA72542D2.jpg269E6A5E-B3A3-4C85-B29C-5D7DC0D34D14.jpgFE220FD2-94EA-47AF-B696-E79D51B41812.jpg
As you can see from the images the lumen of the banjo bolts fits only ONE filament of the 20 gauge wire so any small precipitation or dirt can obstruct this lumen. Also notice how there are only few millimeters between each washer/spacer and the nearby opening in the bolt. So if the non-uniform washers are not installed in correct locations or the banjo bolt is over-torqued while attaching it to the pump, the copper spacers can get crushed and misalignment results between bolt openings and overlapping cylinder heads (as the 2 cylinder heads will get squished towards one another and shift away from delicate overlapping with the bolt opening).

PROPER TORQUE OF BANJO BOLTS 12 Nm (Z4 E85) or 16 Nm (Z3 and M roadster)
https://www.newtis.info/tisv2/a/en/e...le-top/5aM4jyd

[tekoo]

As you can see paying attention to every detail is vital here as any tiny deviation from perfect at the pump side will translate into a huge movement defect at the hinge side.

This is why BMW created the soft top repair kit and recommends a new kit to be used with every pump replacement so the techs and customers don’t take chances with these washers and bolts. Any bolt/washer issues here might pass under the radar and give the false impression the pump/motor unit is defective later on when the roof fails to perform as expected.

It is very possible the non-BMW dealer you purchased your car from didn’t pay attention to any of these details when they installed the new pump so they could have gotten lucky with one banjo bolt alignment but not with the other.

You will need to go through everything again yourself and make sure everything is perfect. Otherwise you may end up paying a lot of money that was not needed.

[celticrider]

I see how critical the washer thickness is for sure.
I didn’t realize this as much as the correct placement of the washers.
I do appreciate all the info you have given, and I am a lot more educated than I was before, and suspect I will be more educated by the time I get this figured out.
If nothing else, hopefully help someone else that unfortunately may run into this strange and unique issue.
I will post my findings once I figure this all out.
Thinking I am narrowing it down.

[tekoo]

You can try and switch only the Banjo bolts with their respective washers without switching the hydraulic pipe lines this time.
If the weak roof movement flips in direction again with this change then all you need for sure is a repair kit with new bolts and washers.

However when you do this little 'switch banjo bolts experiment' you have to limit the 'cofounders'; in other words keep each bolts with its washers as an independent group so things don’t get confused (move the banjo bolts with its current washers as a group, don’t mix washers with other bolt).

Also keep the washers in their current order/orientation when you move with the bolt. This way the exact problem and symptoms can replicate on the other side if the problem is indeed in one of the bolts and or its associated washers and or its current associated washer locations/order (we want the problem to recur on the opposite side so we can confirm). If you change the current washer order or mix up washers we may miss this opportunity and the defect will stay on the same side if it is a washer related problem.

If after switching the bolts and washers nothing changes, then the problem is in the valve part of the pump that delivers the fluid to the banjo bolts. We know the motor and central centrifugal part of the pump are perfectly fine as the pump can generate adequate pressure to move the roof efficiently in one direction, and you can hear the motor working all the time.

So the problem is either in the bolts or the valves and this is the only way to pinpoint more!

[tekoo]

Don't forget to take the time to reprime the pump every time you disconnect and reconnect or empty/fill fluid chamber! And always do your testing with the pump perfectly standing vertical to the underlying surface and with adequate fluid level in the chamber well above the level of nozzle tips.

[JAS1169]

I'm hoping this solves your roof issues. https://z4-forum.com/forum/viewtopic.php?f=3&t=106697

The by-pass might be slightly ajar which causes slow movement in one direction. If you've relocated the motor/pump to the trunk then this should be a quick and ez fix.

If this doesn't fix it then it's the valves in the pump. I've seen posting on the UK forum on adjusting these. However, I have never done these myself. Again, I'm hoping it's a jammed by-pass valve but if it doesn't fix it, I'd suggest reaching out to the folks on the UK Forum for advise regarding adjusting these valves.

- - - Updated - - -

Here's a second posting involving the by-pass which matches your problem. https://z4-forum.com/forum/viewtopic.php?f=3&t=107063

[tekoo]

Thanks JAS1169.

1-He has already verified the by-pass is not stuck (see earlier posts).
2-I have seen the valve adjustment experiment that you are referring to on the Z4-forum before. Even though the OP said it worked initially, he came back and said it did not actually last and problem recurred (you would have to read to the end of the thread to find out).

He can still give it a try here if everything else fails but I wouldn't try to do everything randomly at once or else we will miss the opportunity to pinpoint what exactly is causing the problem.

He is almost there. If everything else fails he can still try the valve adjustment as a last resort. Otherwise the pump will need to be replaced.

[celticrider]

This sounds exactly like what mine is doing. I will check the bypass and the washers on the fittings then the valve
Hopefully one of these issues is the cause.
Snow on the ground so not in a big panic, car is storage in the garage for winter now

[tekoo]

Actually this thread has now become ‘the bible’ of soft top troubleshooting; especially the post-motor replacement (or non defective motor) troubleshooting that you never find on any of the other forums.

85 posts so far with well illustrated and step by step explanations on how to tease out and pinpoint the actual defect.

Hopefully one of the moderators can pin this thread so all future visitors can benefit from this experience.

When my motor stopped working all instructions I could find online were motor uninstall/transfer instructions and defective Microswitch!! When I took my pump out I didn’t even know the bypass pin is supposed to move! Unfortunately I had to learn everything the hard way.

[celticrider]

For reference
14/12 port and valve is for lowering
13/11 is for raising
Although this forum is an invaluable source of information, there are things that are rarely if not at all encountered.
I have learned after many years as a heavy equipment tech, most fixed are found by other people having issues not companies.
I am close to my issue being resolved and hopefully it will help someone else down the road.
A lot of components get changed because it’s easier to replace than to figure out the actual possibility of a smaller problem.
Thanks again to everyone so far for all the advice.

[tekoo]

The problem is that the few people that figure it out want to make profit out of it. That’s why on the other forum no real explanations or step by step troubleshooting is available; because the couple of people that developed the experience started selling their roof repair services to the other helpless members. Members have to choose between either paying them 200-300 euros or paying the dealer 2000 euros.

[tekoo]

I'm hoping this solves your roof issues...XXXX
The by-pass might be slightly ajar which causes slow movement in one direction. If you've relocated the motor/pump to the trunk then this should be a quick and ez fix.

If this doesn't fix it then it's the valves in the pump. I've seen posting on the UK forum on adjusting these. However, I have never done these myself. Again, I'm hoping it's a jammed by-pass valve but if it doesn't fix it, I'd suggest reaching out to the folks on the UK Forum for advise regarding adjusting these valves.

- - - Updated - - -

Here's a second posting involving the by-pass which matches your problem....XXXXXXXX

As you can see in image below the valve adjustment was not successful!
z4 forum.JPG

[tekoo]

See below his second trial here with the emergency release bypass pin. He thinks the bypass pin is defective because when he pumps it things go back to normal temporarily.

z4 1 forum.JPG

His conclusion is actually not correct. The real explanation to what is happening is:

Like the case with celticrider, he has a partial or near-complete occlusion problem located to one of the pump nozzle valves or one of the banjo bolts (in HIS case it actually could also be an air leak due to exposed nozzle causing air obstruction) so the hydraulic fluid that is transmitted from the pump to the hydraulic pipe post that occlusion is very limited (not a complete occlusion). When he pumps the bypass valve the hydraulic fluid bypasses the pump and fills the hydraulic line post the occlusion with sufficient pressure and at the same time drains some of the trapped air -> he releases the emergency bypass valve (stops compressing the copper pin that returns to its non-pressed status) and the pump returns back to its engaged state-> then the power switch is pressed and the roofs gets a boost of power (now that the lines are sufficiently primed with fluid and trapped air has been drained) and comes back temporarily to life before the hydraulic fluid flow soon becomes limited again (due to persistent occlusion) and air starts accumulating in the lines that are not getting enough hydraulic fluid (air is a gas that can diffuse across the wall of the hydraulic pipes facilitated by the vacuum that is left behind inside the pipes from limited hydraulic fluid transport due to occlusion)-> roof looses power again (and since only one nozzle/banjo is occluded, the problem is always limited to either opening or closing the roof but not both).. and so on.

- - - Updated - - -

If the bypass valve was sticky or defective as he suggests, it would not respond to his manual pumping and the lines would not fill with fluid at the first place!!

[tekoo]

z4 1 forum.JPG

Clearly there is no sufficient grasp on the mechanics of the pump here:

If he manually pushed the bypass valve in few times and then released and it successfully and fully returned to it's non-pressed state afterwards (as evident by roof going back to its normal operational status and the positive response to pressing the open/close switches; which means the pump is not being bypassed anymore and generating evident hydraulic pressure in response to electrical stimulation).

So if the copper bypass pin has successfully returned to its non-pressed state (aka pump-engaged state) how can it possibly push itself back in and get stuck into bypass mode again on its own disengaging the pump? The answer is;

IMPOSSIBLE!!!

It is called the MANUAL emergency release bypass for a reason; someone has to manually pull the handle or manually compress the copper pin before it can get stuck in the bypass status (aka pump non-engaged status). This can't occur spontaneously! Even if the pin was partially sticky, once it successfully has returned to default non-compressed state, it can not drop back in, simply because there is hydraulic fluid behind the pin with sufficient pressure to prevent the pin from dropping back (acts like a spring).

[tekoo]

z4 3 forum.JPG
As you can see:
1)problem was never fixed. Notice how OP used all capital letters in 'NOT fixed' which reflects he's either pissed because he was not successful or pissed from repetitive inquiries from other members on "how he did it" when he actually never succeeded in the first place.
2)the guy didn't even perform the pump repair himself; he hired 'number 5' to do it (one of the guys that are selling their service) which means the OP doesn't even have the sufficient basic experience to replace the motor, not to mention fixing valves and troubleshooting advanced problems like this.
3)number 5 doesn't seem to have enough experience either as he reversed both the 2 hydraulic lines as well as the pump polarity/direction (if you reverse twice they have essentially cancelled each other). Also notice how the OP said they were both guessing.
4)The repair only lasted few minutes until 'number 5' was gone ( I have explained why in my prior post).
5)The OP at the end confirms the fact that it seemed like an air leak as I suggested before.

[tekoo]

z4 4 forum.JPG

Here comes the second guy that also sells his soft top repair services. He finds out his competition has failed and wants to appear superior:'it's the valve I have done lots of them' he says.

Notice how he says the system is self bled. This is correct in normal operating conditions during day to day normal functions but when a lot of air is trapped in the lines beyond the pump, it becomes impossible for the self bleeding to occur as the extensive air in the pipes causes complete obstruction of the flow of hydraulic fluid (self bleeding means, along its movement, hydraulic fluid acts as a vessel for small limited air bubbles to leave the hydraulic pipes, which can only occur if hydraulic fluid movement has not completely ceased).

[tekoo]

z4 5 forum.JPG

Notice how the second guy that has 'done lots of valves' disappears afterwards despite inquiring members' questions for details on how to fix the valves. The OP finally decides to desperately attempt the valve repair himself and we know how it went from there and his erroneous bypass valve conclusion. Clearly every attempt here failed as the title remains 'NOT fixed' till today!

Conclusion: 1- emergency bypass valve is not the culprit here, 2-No adjustment so far seems to effectively repair the pump nozzle/valve, 3-We have a more efficient evidence based approach here so we better stick with it

[celticrider]

The confusion continues!
So after checking all the washers carefully, all 6 are exactly the same, which doesn’t explain if the washers were the issue, my problem should be both directions?
So do I take that of the list or order the kit from BMW
Other question, without beating this to death, I know my bypass works, but how much movement is to be in the brass pin
I can push in with my finger and it pops right back out protruding 2mm our from the side of the pump housing

[tekoo]

1- If the bypass valve was problematic and stuck the pump would be completely disengaged (hence the name BYPASS) and that would apply to both directions of movements (opening and closing). The roof would only open and close manually!
The amount of travel the bypass pin actually does is probably less than 3-4 mm max. You can see in this image the movement of the Maximum lever arm where the emergency cable attaches is max 1 cm (which is the total distance the red emergency handle can be pulled). You can imagine how much this travel distance would translate to at the bypass pin location where the lever arm and angle is at its lowest!! Probably 2-3 mm at max!

7CE7DB1D-EB2A-49EC-9319-B6F8D3CAC062.jpg

The Bowden cable of the emergency red handle attaches to the hook end of this lever arm, and when you pull the red ring the lever arm moves towards the pump frame compressing the bypass valve -> Pump becomes functionally disengaged/bypassed from hydraulic circuit.

PLEASE; NO MORE BYPASS VALVE QUESTIONS. IT IS A WASTE TO YOUR TIME!

[tekoo]

Here are more images of my BYPASS PIN. If your valve looks the same and can move when you press it and return back to default position and the hydraulic pump CAN and DOES actually engage and move the roof in ANY direction -> then there is no need to confuse yourself with the bypass valve any longer!!

85C20062-A1E1-41D3-80B1-2EE75BFF6863.jpg0B1F099F-C6E8-43DE-A1D6-C190F084A461.jpgBA9EA5C5-1FE5-43A9-A49C-424C2AF08F56.jpg60ECB2DC-2BDD-4CF3-BF19-2E048E6CB5FC.jpg

ALSO FYI when the bypass valve gets stuck (seized) it rarely happens in the depressed position. Actually quiet the opposite; it is usually seized in the released position (aka pump working/engaged position) as this is the default position that the pin is in for YEARS of hydraulic unit use!!

It’s against the laws of physics that the bypass pin would remain in the depressed state when there is positive hydraulic pressure behind it. Unless someone forcefully jams it in there or the pump has serious structural defect!

[tekoo]

2- In regards to the kit;

It includes new washers and banjo bolts. If you confirmed yours are patent, not bent/crushed and installed correctly then I doubt getting a new kit would help.

I would have swapped the banjo bolts location to confirm the problem is not due to defective bolts (swap only the bolts not the hydraulic lines). Have you done so?

[tekoo]

Bypass valve fully compressed state:
2540C2B3-E793-4FF1-87AA-FD726355F2FD.jpeg

Red handle maximum travel distance ~ 0.5 cm
B5A026F4-869F-4755-8FBE-1D335525B0DC.jpgFB19A9BB-6D1F-4C65-A2A4-24BA2E38BF8F.jpg

[celticrider]

I have not, but they are marked as to what port they came from
Will attempt that tomorrow