Relocated Roof pump but weird problem?

StuUK · Post by **StuUK** » Mon Jul 09, 2018 8:41 pm

Hi All
I had my 2005 E85 2.0 Z4 roof pump assembly refurbed and relocated to the boot.
So the problem is the roof closes every time ie comes out of the boot like a jack in the box no problem!
However, when i want to open the roof it unlatches from the screen then seems to stick.
It clears the roof just so the latches are not sticking but sticks just above the screen
If I help it with a push it continues and opens and latches down in the boot.

So as a test I swapped over each pair of hydraulic lines on the pump and reversed the motor connectors.
This way the roof pulls off the screen no problem at all but sticks coming out of the boot so the exact opposite of the above.

This proves to me that the rams are working fine in either direction as long as they are getting hydraulic pressure.
It also proves that for some reason the pump seems to be working far better in one direction than the other.
The motor seems to be turning equally well in either direction.

I recently acquired another refurbed pump and motor unit and this is acting in exactly the same way.
I am somewhat baffled!

Can anybody help?
Stu

Ducklakeview · Post by **Ducklakeview** » Mon Jul 09, 2018 9:23 pm

Very common - The pumps fail in one direction first, normally the "opening" of the roof. This is because that's the hardest part of the sequence, as the extended roof acts like a massive lever on the rams. Pumps can be refurbished/adjusted.

Mike

bigosean · Post by **bigosean** » Mon Jul 09, 2018 10:05 pm

I had the same issue, Mike sorted mine for me and I’ve had no problems

wonkydonkey · Post by **wonkydonkey** » Mon Jul 09, 2018 10:33 pm

Mine is doing the same thing. If I press the bypass valve in a few times the roof works fine again. Seems the bypass valve is a bit sticky. I've proven it several times over, just need to work out how to get the valve out of the pump body to clean it up!

StuUK · Post by **StuUK** » Tue Jul 10, 2018 8:37 am

Ive tried adjusting what I assume are the pressure regulators under the plastic oil resevoir but no real success.
Ive even modified one of my plastic covers so i can adjust these in situ.
Ive worked out that looking from the top with the hoses at the front the right hand adjuster seems to govern the pressure for the open cycle and the left hand is for the close cycle.
If I back off the LH adjuster to the point where the roof doesnt lift out of the boot then tighten it half a turn thats all it needs.
But even if I tighten the RH adjuster all the way down the roof still sticks on opening.

I'm also suspecting it may be something to do with the bypass valve as this seems to be on the "open" path but my release valve does seem to be working properly.

The only other observation I have noted is if Ive done something major like swap the pump or motor the open cycle will work for the first half dozen times you try it before starting to stick.

This has thrown me a few times thinking I had fixed it only to see it fail after putting it all back together.

wonkydonkey · Post by **wonkydonkey** » Tue Jul 10, 2018 7:18 pm

You're describing the same problems as I have, as per my post above

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