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power hood microswitch bypass/screen washer pump replacement

Discussion in 'Z3 Roadster & Coupé' started by joey, Jul 22, 2013.

  1. joey

    joey Zorg Addict
    British Zeds The M44 Massive

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    hi all


    have owned my atlanta blue zed with tan leather interior for about 4 mths now its a 1.9 auto with less than 46'000 on the clock FSH and two lady owners..not a scratch on it...am so happy with it easily the most fun car I have ever had!

    however a couple of (minor) issues have come up, the most annoying being the at first intermittent power hood failure, I did a search and found the most likely cause was the hood microswitch and have established this is the case, I have seen the microswitch replacement "how to" with the maplins switch and it looks like a good solution..however my question is this why not just bypass the thing altogether? it seems to me as long as you remember to manually lift the hood before engaging the pump/motor then you won't risk damaging the hood and it seems like a "weak point" in the hood design anyway..seeing as i don't intend to sell the car it will just be me using it.
    at present I have disengaged the motor and am using it manually.


    secondly the screen washer pump has packed up, so any recommendations on a cheap but reliable replacement part would be great ,I intend to do the work myself as it seems a simple job to do.


    many thanks in advance for any advice you can give.
     
  2. GazHyde

    GazHyde The Gaz Monkey
    Staff Member Administrator Global Moderator British Zeds

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    Hi Joey and Welcome! :welcome:

    Not sure on bypassing the hood microswitch, but you can try Soper BMW Lincoln for a new OEM washer pump - they should give you a good price ;). Alternatively you may see a second hand one pop up on eBay from time to time.

    Cheers, Gary
     
  3. Aceman

    Aceman Moderator
    British Zeds 3rd Party Trader

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    Hi Joey,

    Yes you could bypass the microswitch by shorting it out but you do run the risk of over extending the the hydraulic ram if you leave you finger on the button too long and then you would have an oily mess but as you say if you are aware of it then you will be OK. It wouldn't take much more effort though to actually replace the microswitch whilst you are at it so I would replace it personally.

    Screen wash pump as Gaz says try @Soper BMW Lincoln if not I seem to recollect there are plenty of non OEM ones available on ebay.
     
  4. joey

    joey Zorg Addict
    British Zeds The M44 Massive

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    thanks fella's for the prompt and helpful replies...


    have just been to Maplins and acquired the microswitch, some wire, connector spades, and shrink wrap and plan to do it at the weekend, re the screen wash pump,phoned BMW lincoln earlier and they will sell me pump for £33 delivered, if anyone can point me to a "how to" either you tube or PDF with pics on the pump replacement I would much appreciate it, or if you have personal experience of this any pointers would be great, I am pretty new to wrenching on cars although did most of the servicing myself on my vespas this would appear to be a little bit different and I lack a few tools..

    the wiki has been very helpful as I also have the "rocking seats" issue as well...


    list of works for a forecourt condition Z3

    1)microswitch replacement

    2)screen wash pump replacement (both this weekend)

    3)seat bushings

    4)new rear window (although this could wait a while as its not to bad)

    both the roof and pump faults have occurred since I bought the car so have been a tad unlucky with that but she runs like a top and is otherwise in excellent condition, as with my scooters though i'm a perfectionist and want it in tip top shape.

    will let you know how it goes after the weekend..


    cheers

    Joey
     
  5. gookah

    gookah Zorg Guru (IV)
    British Zeds

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    Not sure what you mean there, the hydraulic ram cannot over extend, it would just come to the end of its stroke and the pump would then run at full pressure in a closed circuit, just as it does if you hold the open button on too long. If it leaks then the ram seal or hoses were shot anyway.
    The microswitch is not there to switch the pump off, but to ensure you have lifted the front part before opening the roof, as not doing this would bend the framework. It just so happens that it cuts the pump power supply when the front drops down during closing.
    Shorting the switch is possible but why risk it? the cost of the replacement switch is far less than a twisted frame and it only take you once to forget, or it drops down again as the movement begins, then you will have a far larger damage bill and a far longer repair.



    Edit: Just seen you have bought a switch, way to go Joey.
     
  6. joey

    joey Zorg Addict
    British Zeds The M44 Massive

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    yeah ,I make you all 100% spot on re the switch replacement rather than bypass scenario,it only takes me to be in a rush or forget once and its big bill for a new hood time..so thought I would go down the "do it the right way route" although i'm glad the Maplins microswitch can be made to work work as I just got a quote of £58 for the OEM one! yikes...don't know how BMW can justify charging that money for a probably chinese made plastic switch its absolutely unbelievable...

    p.s if anyone can post a link to a cheaper alternative to the OEM windscreen washer pump that would be great, for a newbie ebay is a bit confusing for this as i'm not yet fully cognisant of all the BMW engine numbers and compatible parts.

    once again thanks all...
     
  7. joey

    joey Zorg Addict
    British Zeds The M44 Massive

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    update.....


    hood fixed...maplins switch in and it works great......for the cost of about £9 and 15 minutes of my time..great forum and really useful wiki pages, I have been a member for all of two months and it thanks to the info on here i have already saved £150 ....!

    found a washer pump on ebay for £5.60 inc delivery, removed the reservoir and old pump from the side of it and have it on the garage floor for the the new pump to go in when it arrives on tues.....very simple fix provided of course that the pump is the problem..all investigation so far implies it is.

    bushings next!
     
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