Johnson lzs

I'll be glad if it eventually turned normal. Right now, nothing works. =O

I might dismantle the pump again and have it looked at by my hydraulic specialist. Hopefully he sees something I don't....

cougar694u

I was referencing an internal leak, not external. As in the seal around the ram is allowing fluid to internally bypass somewhere. For instance, the roof lock unlocks, but remains pressurized. If there's an internal leak, the pressure will unlock it, but then begin to flow past the ram and back to the pump through the other line.

Pure speculation, but if there is bypass, it may not have the pressure to lift the trunk, and possibly why the roll bar is slow.

Johnson lzs

Ahh, I see.

Update: I just found out, when installing the all the pipes previously, I accidently "pinched" the pipe for "32" or "92", cant remember which. It was literally folded almost 180 degrees. Might explain why the tubular frame cant be lifted initially. After I disconnected the pipes and reconnected it to prevent the pinching, it still doesn't work though.

But hydraulic pressure seems smoother? Roll bar can raise and lower faster now it seems.

cougar694u

Ouch. That is likely the cause. You have two options. Replace that cylinder or cut & splice that line.
the former is the best fix, but can be impractical, depending on which cylinder.

If you want to go the splice route, this company has the couplers: https://cabriolethydraulics.com/

sparker55

Just a quick note for those checking in on this thread: If you are replacing a hydraulic ram - say on the windshield header - make sure the assembly is in it's original position by marking it prior to disassembly or by going by the original seat marks of the mounting screws. I state this as I utilized cabriolethydraulics.com unit and the vario roof would never fully open or close due to a limit switch which would not activate since I did not have the assembly in its original position.
I realize that this should be obvious to those 'in the know' but I overlooked this aspect and it all boiled down to an 1/8" of adjustment. Hope this helps...

cougar694u

Good shout! Just because you know something doesn't mean everyone knows it.

peterkay

Did that issue ever get resolved? I am having the same problem. Had the pump rebuilt by top hydraulics and at wits end to understand why the pressure is low

cougar694u

How old is the car and have you replaced any other hydraulic cylinders?

How are you testing pressure?

peterkay

Mine is 2003. I follow the procedure that top hydraulics have outline. Use their syringe to force fluid into low pressure port until clear liquid comes from the high pressure port. I replaced 4 cylinders: headliner, side locking and rear trunk lid raise. My roof times out at the point where the trunk raise cylinder should be activated. The roof unlocks, the windows go down, the side corner raise and this is when it just seats. If I try to close it - nothing works, I have to do it by hand.

cougar694u

Can you raise & lower the roll bar?

peterkay

Yes I can but the motion is slow and jerky. Here is what I am doing tonight - I got a crap cylinder. I am cutting the lines off it and use the end pieces as plugs to seal ports 100 and 60 which correspond to the roll bar cylinder. Then I will try to operate the roof to see if there is any difference. My hypothesis is that the internal seal on the roll bar cylinder has failed and causing a pressure bypass at the pump which leads to insufficient pressure to raise the trunk lead. What do you think?

MikeJ65

That would be my first guess as well. You should have eliminated most of the possibilities with the pump and those four cylinders being replaced. Could be the main cylinders, but I think roll bar is more likely based on how it is moving. Also, remember that the front latch, two frame latches, and the trunk lift cylinders are all on the same circuit. Trunk lift is activated, just not seeing enough pressure. It probably wouldn't be a bad ideal to check/replace the gas strut that helps lift the right side of the trunk. I think it should lift regardless, but the gas strut helps balance the loads so the the trunk lift cylinder doesn't apply a large side force.

peterkay

I was thinking about this. Do you have a part number for it? I cannot seem to find it

MikeJ65

Part 230-750-01-36

peterkay

Thanks!


Well, I tested it. The pump certainly builds up pressure, Even after I released the pressure, when I was taking the bolt near the line 100 - the residual pressure bent the plate!
Now, the system is doing something totally cockeyed. Only the left unlock cylinder is working.

I suppose I will be sending the valve block back to top hydraulics and see what they find.

peterkay

Also, had anyone made a hand pump to verify the actions of individual cylinders?

MikeJ65

Did you replace all four cylinders with rebuilt parts? Also, have you double verified the every line is in the correct position? Roll bar cylinder holding pressure would seem to verify that it is okay. A bad piston seal would allow line 100 to drain back across the seal and into line 60.

peterkay

Yes, all four were rebuilt. Klaus at top hydraulics thinks that the pieces of old seal are contaminating the oil and this blocks the valve body