How to fill hydraulic reservoir for roof pump?

Dergolf · Aug 15, 2021

Hello from Denmark!
T5 California 2006:
I have just now replaced both hydraulic rams after one was exploded. (it had pushed the bottom end cap off, in sunny spain)
Lost a lot of fluid there.
So i replaced both rams.
First try after replacment i could only open the roof about 20%.
So i could not figure out to remove the headliner here and now.
So i used the ram i removed to pump new hydraulic fluid in the system. Like a bicycle air pump. Also one stroke before it get very tight.
Did it first one the "exploded" side.
The roof now could open about 70%.
Did the same thing one the other side. But not much fluid could i press in.
Now the roof opens about 80 %.
I'm pretty sure the system need more fluid.
I think i have to remove the headliner for get to the reservoir.

I found a thread about it

As promised: Changing the electrohydraulic roof pump!

So as I promised last year, I wanted to keep you updated about changing the electrohydraulic roof pump. Therefore we need: a pump, some guts, a bit of spare time, and some helping hands. Up to now I only have the pump and the headlining taken off. First we take off the A-pillar handles...

vwcaliforniaclub.com

There a some things i don't understand in this tread.:
Then you unscrew the top bed light, loosen the felt tape on the runner, drill out 2 rivets on both sides and lift up the sliders (after opening the roof). Just drill out the heads, and leave the rest of the rivets in place. So you can clip on and off the headlining, in case you should need to remove the headlining again later (like I did because of a pinched out water drain):

What is felt tape?
What is the runner?
Where a the rivets who needs to get drilled out?
Sliders?
Please explain.....

Sincerely...
Michael

WelshGas · Aug 15, 2021

@TripleBee , help needed.
He is the author of the above.

TripleBee · Aug 15, 2021

Dergolf said:
Hello from Denmark!
T5 California 2006:
I have just now replaced both hydraulic rams after one was exploded. (it had pushed the bottom end cap off, in sunny spain)
Lost a lot of fluid there.
So i replaced both rams.
First try after replacment i could only open the roof about 20%.
So i could not figure out to remove the headliner here and now.
So i used the ram i removed to pump new hydraulic fluid in the system. Like a bicycle air pump. Also one stroke before it get very tight.
Did it first one the "exploded" side.
The roof now could open about 70%.
Did the same thing one the other side. But not much fluid could i press in.
Now the roof opens about 80 %.
I'm pretty sure the system need more fluid.
I think i have to remove the headliner for get to the reservoir.

I found a thread about it

As promised: Changing the electrohydraulic roof pump!

So as I promised last year, I wanted to keep you updated about changing the electrohydraulic roof pump. Therefore we need: a pump, some guts, a bit of spare time, and some helping hands. Up to now I only have the pump and the headlining taken off. First we take off the A-pillar handles...

vwcaliforniaclub.com

There a some things i don't understand in this tread.:
Then you unscrew the top bed light, loosen the felt tape on the runner, drill out 2 rivets on both sides and lift up the sliders (after opening the roof). Just drill out the heads, and leave the rest of the rivets in place. So you can clip on and off the headlining, in case you should need to remove the headlining again later (like I did because of a pinched out water drain):

What is felt tape?
What is the runner?
Where a the rivets who needs to get drilled out?
Sliders?
Please explain.....

Sincerely...
Michael

felt tape:
https://www.amazon.nl/dp/B00PAC9OAK/

the rest:

Dergolf · Aug 15, 2021

Thanks for your fast response! //Michael

TripleBee · Aug 15, 2021

Dergolf said:
Thanks for your fast response! //Michael

I hope you can sort it out.
Once you know how to do it, it's not that hard, it's just a lot of work.
Let us know the outcome!

flying banana · Aug 15, 2021

Keep raising and lowering the roof. That will bleed the air out of the system

speedo · Aug 16, 2021

How did you get on Dergolf.?
Have you managed to sort it?

I recently had a blown hydraulic pipe. It was down to poor fitment, as it had rubbed through, rather than component failure.
Any way, I had to purchase a bottle of the most expensive oil in the world.
£75 for 500ml.
Only seemed to be available from VW..
I used a max of 50cl., so if any body needs some, I'll put it up in the classified section, when I'm back from holiday (Next week).

yanathem · Aug 16, 2021

I can maybe help here. I’ve recently had a ram explode on the hydraulic roof. Replacing the ram is pretty easy which you already have done.
Getting at the pump is a bit of a pain but not impossible to remove without removing the headliner. You will already have the control panel out to have been able to access the valve to lower the roof. Remove the light fitting and sunglasses holder. The frame has four screws two you can see once the sunglasses holder is removed.The other two are underneath the lamp lens. The lens is held in with a spring clip. Once all four screws are out and the electric connections to the control unit and light are disconnected, the plastic frame can be removed. The pump then can be got at by either cutting the foam surround neatly with a knife or do it like I did just pull it and it snaps in half. A plate holds the pump tight, just remove that and then the pump is loose. Next try to push any wiring into gaps to make room to move the pump sideways to your left (looking through the glass windscreen.) that should give enough room to be able to angle the pump down and with a bit of tugging it should come out enough to be able to get at the filler cap.
The next stage is where an extra pair of hands is needed. If there is any fluid left in the pump reservoir, use a syringe with a tube long enough to suck out any of the remaining fluid. Might as well fill the pump with fresh new fluid. Connect the control panel electrics so you are able to access the roof up/down control. Use the same syringe and tube to add fluid. Depending on syringe size ( I used a 100ml syringe) Add fluid, cycle the pump upwards to draw fluid into the lines, repeat until the procedure until the roof starts to move. Oil level is a guessing game but get enough in so that when the roof is fully up you still have fluid in the reservoir and once down fluid doesn’t spill out of the filler valve. Cycle the roof a few times with the filler screw loose or removed adding more fluid necessary if low. Don’t overfill it will be messy. As a precaution I had towels and plastic sheeting draped underneath and on the seats in case of a spillage. I used around 240ml of new fluid.
I hope this helps, I think the first time getting access to the pump is daunting it certainly was for me. I’m not a mechanic or work in hydraulic systems, no undercover access either, it was done on my drive at home by myself with basic tools most people will have. It’s not a difficult job just unnerving that you might break something removing the roof control frame. The pump is well engineered so I wouldn’t think a lot can go wrong with this, really unlucky if it does or has. The hydraulic rams though are a very cheaply made product that are very costly to purchase, I paid £403.00 for just the one ram. Why the end cap is not screwed on with a locking wire through it is any body’s guess even the new “improved”one looks rubbish.

Dergolf · Aug 21, 2021

I finished the job today. Loosening the headliner in the right side and almost in the left.
Loosened the pump and sucked out the old fluid. Refilled it with brand new and refitted everything. Everything works. I did some improvement to the rams. The plastikcover got a layer of aluminium tape (aircraft repair tape). See the picture.
Thanks everybody for your help. //Michael

Dergolf · Aug 21, 2021

BTW the expensive hydraulic fluid feels and smells like the hydraulic fluid "my job" uses on planes....But im not sure.....i used the VW stuff

yanathem · Aug 21, 2021

Dergolf said:
I finished the job today. Loosening the headliner in the right side and almost in the left.
Loosened the pump and sucked out the old fluid. Refilled it with brand new and refitted everything. Everything works. I did some improvement to the rams. The plastikcover got a layer of aluminium tape (aircraft repair tape). See the picture.
Thanks everybody for your help. //Michael

View attachment 83365

I read that was VW’s fix and to drill a hole in the same cap to release heat because it was heat VW thought was causing the rams to explode. I’m not sure heat is the cause though. Ours blow on a typical northern British afternoon. I.E cold and wet. It was breezy though, personally I think this is what might have caused ours to explode. Maybe just the rocking motion of the roof in the strong breeze was enough to make one ram explode. I’ll probably never know what caused it. But I am pleased it’s a job that I can now do by myself if the other side fails.

dlewisjo · Feb 3, 2024

Dergolf said:
I finished the job today. Loosening the headliner in the right side and almost in the left.
Loosened the pump and sucked out the old fluid. Refilled it with brand new and refitted everything. Everything works. I did some improvement to the rams. The plastikcover got a layer of aluminium tape (aircraft repair tape). See the picture.
Thanks everybody for your help. //Michael

View attachment 83365

Hopefully you can help, I’m following the same process outlined in your post but I’m stuck.

I removed all the parts to get to the pump motor to check the oil level, but I have a block of foam, and don’t see the metal plate you refer to. Also, there is a plastic strip in the way holding the foam block - see green arrow in pic.

Did you have the same problem ?

yanathem · Feb 3, 2024

The metal plate and pump is behind the foam. More than likely the foam will snap removing it. Don’t worry if it does it’s job is just there to soundproof and it will go back in place if it does break.

dlewisjo · Feb 4, 2024

yanathem said:
The metal plate and pump is behind the foam. More than likely the foam will snap removing it. Don’t worry if it does it’s job is just there to soundproof and it will go back in place if it does break.

Appreciate the reply. I’m not sure if things changed around 2015, as mine didn’t have the metal plate when I cut away the foam. Although my van is 2008, there was a date stamp of 2015 on the foam, so I’m assuming it was changed when it went in for the roof corrosion fix.

I ended up removing the trim around the roof opening/sliding roof cover, and lowering the roof lining, just enough to access the two remaining screws so I could remove the black plastic strips.

Basically, the pump is sandwiched between two pre moulded foam blocks, so the pump fits nice and snug, and the black plastic strip holds the foam block up.

Looks like I’ve found my problem though, very low oil. Pain that the oil min/max level markers are on the opposite side of the reservoir, so I put my own on.