Roof repair

M

MX7

Member
2005 Z4

Upon pressing the button to drop the top I could hear the motor running but other than the roof unlatching, no movement.

Did some research and saw a couple of videos on pulling the motor into the trunk/boot. For started and couldn’t snip the wire ties to free the motor. This was done several months ago and a back issue prevented me from twisting my body the right way. Back is feeling better and I’m about ready to give it another go.


Before I do - any suggestions/advice?

I am located on Long Island/NY and if there’s someone w/experience that might be willing to take this on that would be great.

Thx!
 
I came up with a different way to access the motor. If you take out the left seat, and put your left hand and arm through the rollbar, you can reach into the side pocket and access the motor.

When I tried it, I had already pulled the top off with a crowbar through the boot. (Very Difficult) However, I am pretty sure you can carefully cut the tape with a razor blade and pull the motor out. It is probably much easier if you are left handed, (which I am not) but can be done if you are not.

I originally accessed the motor through the boot, but found out I could put fluid in the motor using this rollbar way. I can even do it when the seat is still in the car, but taking it out would be much easier.

Unfortunately I was not able to break the zip tie that holds the cup in the car, but that is mostly because I couldn't see it. I think with a little effort it can be done.

Also, there is enough room for you to see the different components with a flashlight.
 
Thanks for the response. I’ve had the seat out before - easy to do with the top down. I don’t remember being able to see the motor - but I’ll take another look in the morning. I can see the motor and wire ties through the boot - just couldn’t contort my body in such a way to snip the ties. As you say being right handed certainly doesn’t help.
 
Honestly, your best bet it to remove the roof. It's simple, but takes two people to prevent scratching the car,
Once you have it off, you can see where it is leaking fluid. My guess would be one of the two hydraulic hinges. Replace the hinge and relocate the motor into the boot!

Take care!
 
I’ve watched a video or two on removing the roof. It doesn’t look hard, but it is a lot. Not sure I want to take that on, which is why the method of pulling the motor into the boot was attractive.

Where are the hinges located? Is there an exploded view or photos? If I do decide to tackle the roof, I want to be sure I know exactly what I’m doing before I jump in.

Thanks for the response/suggestion.
 
The hinges are two, one on each side right behind the door of the car.
They commonly fail and leak. Filling up the pump only makes it work temporarily, until it leaks out again.
When I took my roof off, the motor was really secluded in a cubbie thing, I think it would be very had to pull it / fill it in any other way. Sometimes doing the easy job may be harder and longer than doing the full job.
 
enuff_zed said:
Just to clarify, 9/10 times it is the pipe to the ram that leaks, not the ram itself
Click to expand...

Really, are they generally considered a common fail item? I definitely have a leak in the hinge itself so that needs to be repaired in any case. I'm now wondering should I replace the hydraulic hoses as preventive maintenance or not, since they are not cheap. The hoses look fine, the motor is clean and dry. I wouldn't like to throw extra 200$ for the lines, but then again, I wouldn't like to take the roof off again next year ;).
 
In the uk we find the lower pipes on each ram corrode where they get wet then holes appear in them. If yours are good and clean then no worries
 
enuff_zed said:
In the uk we find the lower pipes on each ram corrode where they get wet then holes appear in them. If yours are good and clean then no worries
Click to expand...

Actually, upon closer inspection after your comments, one of the lines is not ok:
IMG_2657.jpg

The picture is very close up, the damaged area is less than 1 cm in length in real life. Damage seems superficial, there are no deep cracks or anything. As said, the rain drains are not clogged so I'm suspecting that damage to the line might have been caused by slow leak of hydraulic oil to the pump cavity, you also can see some of that residue in the picture, on the plastic housing. Do you think that damage is severe enough to consider replacement of the lines, or can I seal that somehow and prevent further damage?
 
I think if it were me I would change that line. Hopefully you can get it locally but if not, I can look at the cost to post good used ones to you.
 
enuff_zed said:
I think if it were me I would change that line. Hopefully you can get it locally but if not, I can look at the cost to post good used ones to you.
Click to expand...

OK, thanks for comments, much appreciated. I'll look into my local options first.
 
MX7 said:
Before I do - any suggestions/advice?
Click to expand...

First, as DashingDaryl wrote, you can reach to the motor from front. Boot shelf and the plastic parts above the pump removed, with the seat forward and upright there’s some room to reach the case. To cut the zip ties I had a cheap usb cam taped to a pair of scissors:

IMG_8289.jpeg
IMG_8292.jpeg

[youtube]kqDzdEJI8yQ[/youtube]

With the zip ties cut, the final plastic tab on the motor housing was broken en brute force - pushing the case top backwards, iirc. After that, easier to dive into the boot and pull the unopened case into the boot.

IMG_8365.jpeg
 
After a struggle I’ve been able to pull the pump and motor into the boot. I had the motor replaced years ago by my mechanic. At that time it came out soaked and a big hunk of rust. This time it looks practically brand new. Hmm….

I was thinking of jumping 12v from the battery to see if the motor turns - but I’m certainly willing to drop a few $$$ on a new motor. I was thinking of replacing the motor only. I am in the US - can someone suggest a source for an aftermarket motor?
 

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I don't believe you need a new motor. Buying a new motor would be a waste of your money.

You initially advised you could hear your motor running when you attempted to bring your top down, but no movement. Generally, this means you have a hydraulic leak or the pump head on top of the motor failed. However, looking at the picture you posted of the motor/pump it is looks almost new.

In all likelihood either a hinge lifter seal failed, or you blew a hydraulic line. The only true method of determining this problem and then repairing it is by pulling the top. If it's simply a hydraulic line the repair part and labor will be costly if done by a third party. Whereas, if a hinge lifter, the part and third-party labor cost involved could be very expensive. Avoid the dealership on this one.

If it's a hinge lifter, DO both at the same time. You don't need paying the labor cost and then two months later have the other hinge lifter fail.
Also, have your hinge lifters rebuilt. There are two venders who rebuild convertible hinge lifters, one in the State of Washington and the other is in Florida. Google BMW Convertible hinge lifters for these vender
 
Jas - thanks for your response/advice. A couple of thoughts…

I was thinking it’s NOT a hydraulic leak for the following reasons:
- no visible signs of hydraulic fluid (I have a Saab convertible that needed a cylinder rebuild. I knew because the headliner had a big stain).
- when moving the top by hand today - it is rather difficult to move (the system feels pressurized)
- when I pulled the motor into the boot today the opaque reservoir looks to be about 35-40% full of fluid with the top up.

Also - when I depress the button there is no longer any sound of the motor running - but perhaps that’s because I have the shelf out? I don’t know where but I’m assuming there’s a micro switch somewhere that’s not being made.

If I knew where the micro switch was I could jump it and then see if the motor still runs when I depress the switch. If the top won’t move but the motor runs - I’m thinking it’s the pump.

I really DON’T want to pull the top unless I absolutely have to. The car sits outside - so pulling the top and then sourcing parts and/or sending them out for rebuild will take weeks with the car outside with no top.

Can you help me locate the micro switch - and are there other ideas on how I can confirm it’s a pump issue or a hydraulic leak?

Are there any
 
Please see the attached youtube. On the location of the micro-switch & how to bypass it

https://www.youtube.com/watch?v=2dzelJUkGfk

I thought you were losing fluid?

You should be aware that hinge lifters fail two ways. The most common is the seal fails and leaks out hydraulic fluid, stopping the top from moving while the motor is running. The second is the rubber rings around the piston within the hinge lifter break/fail and hydraulic fluid simply pass thru the broken rings rather than pushing the piston. There is no fluid leakage with the second kind of failure and the motor runs without top movement.
 
Other causes for the loss of hydraulic pressure would be a jammed by-pass valve at the pump head (the red handle in the trunk goes to this) or the pump itself failed. However, your pump/motor looks like it was installed 6 months ago. I mean it could be the valve/pump but it is very unlikely. If you had a leak, it might be a hydraulic line but, you say you have fluid in the pump head.

However, the only remaining parts of your system are the two hinge lifters, which I'm guessing are as old as the car, at least 18 years old and have rubber seals and rings.
 
Today I jumped out the micro switch. When depressing the button the unlatching motor now runs (as expected) but I don’t hear the hydraulic motor running at all. I am going to have someone press the button while I hold the motor in my hand to be sure - but my next step will be to buy either a motor OR the motor and pump. I actually thought I had one in the garage (which is a MESS) but couldn’t find it. Maybe good motivation to clean the garage. Unfortunately the ESG error I’m getting is still kicking my a**. I’ll post the latest on that thread.
 
A word of warning for anyone who's taking the hinges out. Be VERY careful when removing the two main T40 torx bolts. They are thread locked and very easy to strip out. I stripped one of the bolts and just spent two nights drilling it out. I probably lost 5 years of my life due to stress, trying not to damage the roof or the hinge while drilling. Royal PITA is an extreme understatement :headbang: .

So, use an impact tool to initially loosen the bolts, apply WD40 or similar, and let it sit for a day or two to take effect. Then slowly start undoing the bolts. It helps if someone holds the roof in place. Don't force it, if it does not come loose, you will strip the bolt. Apply more lubricant and let it sit longer.

Hope this helps someone to avoid the nightmare I just went through.
 
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