Roof slow in one direction - NOT fixed

W

wonkydonkey

Senior member
Somerset
My roof used to be slow to close. I could hold the "close" button for 5+ seconds and it would only lift an inch and go no further, with the motor spinning away happily. If I then pressed the "open" button for just a second or two and then pressed the "close" button again it would raise the roof all the way.

Number5 relocated my motor and swapped my raise/lower hoses around (and swapped the power cables accordingly), because we both thought the pump could just be a bit weak in one direction. Using the weak side to lower the roof with gravity assistance seemed like a good, logical move, and it seemed to work on the day. I'll say at this point that Number5 did a great job and the roof worked really well over and over again before I thanked him and waved him on his way.

Now that the car has been standing a bit, it's sluggish to open the roof, and is behaving just as it did on the close operation before we reversed the pump function. Again, the motor is spinning away as it should, but the roof won't even open enough for the latches to come out of the windscreen. If I close it fully again and try again to open it, it performs better.

Do we think maybe the pump itself needs replacing (not the motor)? Its behaviour makes me think there could be air in the system, but also makes me question the bypass a bit. Number5 freed that off (it was a bit stuck) and I've wedged it in the non-bypass position but perhaps these wear in time and allow leakage?
 
Mine has the same symptoms .........how would i adjust it......all is in the boot... so easy access ....Thanks .
 
[ref]George7[/ref] I drained and removed the reservoir, exposing two adjustable restrictors. Using the correct allen key I turned one of the valves clockwise 180°, hoping to increase the pressure a little. It was a 50:50 guess as to which of the two valves I adjusted as I didn't know which port was "roof up" and which was "roof down".

[Image removed to save confusion - this was not the solution, merely coincidental]

I lucked out and my roof was immediately working really well. Job done, happy! I was going to wait a bit longer to post my findings, once it had a good week or two under its belt, but all does seem well :thumbsup:

Edit: This did not fix my problem. It returned soon after. It's an intermittent bypass valve issue.
 
Great ......so its a straight forward job ..............any gaskets or seals involved ..........To get things right .....i empty reservoir.......it that a Jubilee clip that i then remove ............clean ......turn right hand screw as per picture . the refit parts and refill reservoir ........and test .
 
Umfaan said:
Great ......so its a straight forward job ..............any gaskets or seals involved ..........To get things right .....i empty reservoir.......it that a Jubilee clip that i then remove ............clean ......turn right hand screw as per picture . the refit parts and refill reservoir ........and test .
Click to expand...
The only seal involved is the O-ring that the jubilee clip clamps the reservoir against. The O-ring on mine looked fine so I didn't replace it.

Text removed as it was a red herring. This problem turned out to be the result of an intermittent bypass valve issue.

I think that's about all the help I can give, but feel free to ask any more questions you may have and I'll do my best to answer.
 
[ref]George7[/ref] happy days. If you haven't owned the car very long yourself, it's possible that someone else has been in there and not topped up the fluid correctly. Fingers crossed for no leak :thumbsdown:
 
Had it for 2 years and replaced the whole roof due to it having no glass in it at purchase, relocated motor after finding it swimming, but seem to have to top up reservoir a couple of times a year, no too confident with torque of filler grub screw so maybe leaking there
George
 
Update: My roof opening operation has been having some weak moments again of late. I decided to remove the motor again to investigate. Long story short, my problem is being caused by the bypass valve after all.

Having stripped and cleaned a number of components I replaced the motor and all was well for three or four operations, then it went slow again.

I've now discovered that if I pump the bypass in and out a few times by hand, the speed returns. One or two roof operations later and it's back to being slow. Pump the bypass again and the roof opens perfectly. The sticky bypass valve coincides with a rapid drop onto the top of the windscreen if I pause the "close" operation with the roof a foot above the windscreen. Once I've pumped the bypass valve, the roof will hold itself a foot above the windscreen if I repeat the test.

So my bypass valve needs attention and I don't know how to service it. It appears it can only be removed from the manifold by using an extremely thin-walled 5 mm socket. Has anyone done this before?

(My tests were carried out with the bowden cable and plastic housing removed from the manifold, so the valve itself is the problem here, not the cable)
 
I seem to have the same issue, roof wont go down without a nudge. Goes up fine. Swapped the hoses around and the problem is reversed. I assume the pump has some check valves in it which maybe one isnt seating correctly in that direction. I have stripped the pump as much as i can but I cant see anyway to get to the inner workings of the valves.

Any ideas?
 
Hey guys
I am wondering why the by pass would affect only one direction.
I am having the same issue of roof not wanting to lower or open
There is a new pump installed last year and the cylinders were rebuilt just recently due to a leak on one cylinder.
The problem has been happening for the last year.
It always unlocks from windshield then only lifts an inch or so then you have to help it to open, then it will most of the way open, until it Is supposed to lock then you have to push down to lock.
It always raises real fast however.
Today I reversed the hoses and the problem switched to hard to raise and lowers fine.
I was investigating the valves as a problem but can’t find any information this side of the pond.
If I adjust, what is the pressure to be and can the ports be dead headed with a guage.
Any help would be appreciated.
 
[ref]celticrider[/ref] I didn't find any information about how to adjust the valves either. Frustrating really, as it can only be a simple adjustment. I don't fancy randomly going through all the possible combinations of adjustments when it's such a slow and messy process to empty and refill the reservoir each time. I did want to remove the bypass valve but couldn't find a socket with a thin enough wall, and I don't want to buy a new pump because it shouldn't be necessary.

I can get my roof to open every time by pressing open for about 1 second, immediately pressing shut for a second or so, and then going back to the open button and holding it. I do want to fix it though!
 
Hey again
The one thing I did manage to find is the 14/12 numbers on the pump is for the lower function and 13/11 is raise
At least it narrowed down as to what valve does what.
I have not been able however to find the pressure adjustment setting so I could compare the two valves, or get a parts breakdown to see if there is a seal on the actual valve under the spring.
Not hard to adjust, but without a guage and actual setting it’s a shot in the dark.
The rebuilder said if pressure set too high can ballon the cylinders and they won’t honour the warranty.
After 750.00 Canadian, not sure if I want to risk it.
 
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