How To Guide Z4 roof motor relocation to boot

Davz

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Yes the resevoir is on the top of the motor and sitting near to vertical.
 

gookah

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are the 2 wires back on the same way, tried swapping them over?
maybe trying to close a closed roof?
 

Davz

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You must have been reading my mind! Yes I checked the connection and it was correct, however out of sheer frustration I swapped them over and it made not a blind bit of difference!
 

gookah

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try opening and closing the override valve whilst pump is running.
try also short on off burst rather than running for longer. Sounds like pump needs priming but is not getting oil into it.

without the pump running, crack open one or both of the hoses slightly on the pump body til you get oil running out,
last resort do that whilst running but cover it with rags.
 
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Davz

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DSC_0823.JPG
Sorted!
Thanks for the advice but unfortunately that didn't work.
I ended up taking the hydraulic lines and Bowden cable off to get it out of the boot.
There is a brass hexagonal pin that the Bowden cable pushes against when the emergency release is required. This pin activates the release valve but due to oxidisation it sticks in, so not matter what you do it will never build up hydraulic pressure. A bit of wd40 and pushing it in and out a number of times frees of the valve.
Once the hydraulic lines were reconnected it worked first time and really fast too!
Reading BMW tsi's I have found that you mustn't fill the reservoir to full, there is a + on the side of the reservoir and this is the fill level.View attachment 112421 View attachment 112421
DSC_0824.JPG
 

gookah

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Glad you're sorted,

yes the reservoir must have some space left for oil to go back into it from the small ram, when the roof lowers
 

Jason Lodge

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Apr 7, 2019
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I’m finally getting the chance to do this. Stuck at the removing top part of plastic case around motor, can only get a small bit of the black tape off. No matter what I use as a lever the top won’t separate. No sign of any cable ties giving way either to allow the case to be lifted out. Agh!
Update, it’s out!!! Cut a small hole in the lid and used long grips to pull lid away with one side of the grips in the hole and the other on side. Now to clean up the motor.
 

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Jason Lodge

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The motor and pump work fine after drying out and cleaning up. But turns out I have a leak in the hydraulic hose! Quite close to the pump so I can see fluid squirting out. How do I go about fixing holes in pipes?!
 

John Sanders

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Sep 1, 2019
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Hello everyone. Have just joined the forum having received a url for Gookah's original post re motor relocation etc. Finally got around to removing the motor and with usual cursing etc, have now got it in the boot and separated from the hydraulic unit. The motor was a rusty mess and having spayed it with CRC/WD40 and left it overnight, proceeded to clean as much as possible. Still looks ugly but way better than when I started. I haven't got around to connecting it to a battery to test yet as I don't have cables/wires. Before I do that I thought I would ask one question, having read all the previous posts to avoid asking something that is already posted. The shaft moves, but is very stiff and not free like I would have expected. I have used more CRC this morning after cleaning and although a little freer, still stiff. Does that indicate anything to the experts? Possibly stuffed? Thanks a lot
 

John Sanders

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Further to my post above, I connected the motor to a battery and it works!! Cant imagine something that has sat in a rusty plastic pack, surrounded by a watery mess, could actually work. These motors must be unbreakable.
 

Appoooh

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Aug 25, 2019
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The roof in my partners Z4 has failed so I thought I'd have a poke around in the boot to see how hard all this really was. I got the shelf out ok but I was not able to separate the top part of the motor housing from the bottom half. I removed a fair bit of the tape but clearly it wasn't enough as I can't even feel where the two pieces join. I was able to unclip the cables from the front of the housing though (verified using an endoscope camera hooked up to my phone).

I was thinking that the next step might be to drill a hole in the top part of the housing and then attempt to rip it off using a pair of pliers.

Are the two pieces really just held together with tape? It feels super solid.
 

Appoooh

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the plastic container the motor is in is fixed to the hood hinge with a cable tie & a small tang if you stand by the passenger door & remove the rubber cover & with a long knife cut the cable tie & the plastic side piece the whole lot comes out in one piece.
When you say rubber cover do you mean the rubber passenger door window seal or something else?
 

Appoooh

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Appoooh, did you manage to get sorted?
I lacked the confidence to rip out the housing so I gritted my teeth and took the car to a repairer instead. In some ways it was a good thing that I did because after he took the roof off he discovered that the motor/pump assembly was in fact ok, it's the left hinge/ram that's leaking. Unfortunately the hinges are even more expensive than the motor/pump assembly so instead of buying one replacement I intend to have them both rebuilt.

The part numbers are 54347193448 and 54347193449 respectively, you can see them in the diagram below.

https://www.realoem.com/bmw/enUS/showparts?id=BT52-EUR-01-2005-E85-BMW-Z4_30i&diagId=54_0313
 
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Appoooh

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BTW the guys who are rebuilding my hinges have their very own highly polished guide to relocating the roof motor to the trunk, have attached it below.
 

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Davz

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Glad your getting sorted, devil that the ram is leaking, as far as I'm aware you can only get the ram out by taking the roof off.....I bet this is gonna cost plenty! At least you'll have the pleasure of top down motoring......nothing like the sound of a straight six at full chat!
 

CrazyOneToo

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Aug 3, 2019
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and most importantly have a beer, knowing that it will no longer get wet, It is easy to get to, and top up if required.

Over 2 grand to fix from BMW,
I did it for free.
What year is your wifes Z4? Also is the plastic casing to large to fit behind the carpet if I was to refit the motor and pump back into the case after relocation?

Thanks for the great DIY!!!!
 
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CrazyOneToo

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Aug 3, 2019
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Glad to help. Several weeks ago I decided to tackle my dead top motor and it was quite the project. I was determined to complete the repair through the boot alone, however the previous owner had gone nuts with zip ties so I ended up having to unbolt the rear section of top to access the pump/motor assembly. Once removed, I tried all the usual tricks to revive the motor but it was toast so I decided to replace it. But after pricing new oem, I followed a tip (thanks YouTube poster) and purchased a used (with warranty) 2014 Ford Mustang pump/motor from a seller on eBay. There are lots of them on there cheap, and model years 2008-2014 will work.

The Mustang unit is the same German manufacturer as the oem BMW, but the Mustang's is at least 25% larger. It is virtually plug and play as the hydraulic lines swap right over, as does the shorter BMW oil reservoir which I needed for clearance in its new location. I mounted the assembly vertically by zip-tying it to an L bracket I mounted with a self tapping screw in a corner of the boot. I then wrapped the motor/pump in a section of grey split foam plumbing insulation, which matches the oem carpet quite well. And..done.

The result? The top operates at warp speed now, and is super quiet. I can top up and bleed the hydraulics in place, and access is two snips of a zip tie. I encourage anyone reading this to consider this upgrade for your Zed, you will be a happy camper. View attachment 93069 View attachment 93070
Do you by any chance know the part number for the motor you replaced?
Just want to make sure before I order and attempt the relocation.
Thanks
 

Davz

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Location
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Crazyone, there is no need to replace the motor, you are looking at £600 from BMW. Put your motor in a container of diesel overnight, in the morning squirt the brushes with wd40 or my favourite gt85, a few light taps with hammer to free the brushes and it will work when reconnected, if it doesn't tap it lightly when it is connected....run it at full tilt for a couple of mins to clean up the rotor and brushes.
 
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