Now that you guys are all talking tops again, let me run this by you. I have the pressure relief valve installed. The pump is full of pentosin. About halfway up, the top stalls and the pump sounds like there is air in it. (Just my impression of the sound). If I stop the action with the switch and then start again, most of the time the top continues up. Sometimes it takes a very gentle push up to get it going. Then all proceeds as normal. I don't see any leaks and I'm not losing fluid level in the pump. Any thoughts?

 

This system is self purging and may take a few operations to get all the air out. As for the roof pausing, my roof does on occasion but I do not let off the button. This system is a positive operation because of the hyd fluid. If it were air it would be a different story. Give it time and remember that the pressure was reduced from 1600psi to 1000psi. Everyone should understand that you installed a pressure valve. It will not break if you hold the button and let it do its job.

 

Assuming that your problem isn't air, my guess is that you don't have enough pressure to get it over the hump. If you look at the graphs on Gus' site you will see that the maximum operating pressure is just as the top reaches the apex which is right where you describe the top stopping. After that it gets a gravity assist as it reaches the cross pillar. Ignore the dead head spikes to 1600psi at the end of travel as these are what the valve is designed to remove.

The relief valve is calibrated based on what we saw with a couple of cars. Your car roof could be one that isn't as mechanically efficient thus requiring more pressure to get over the hump. It could be rubbing on something or maybe there is more friction as it is a complex mechanism. The relief valve can be adjusted quite easily to slightly increase the pressure by clockwise tightening the hex adjuster screw at the pointy end. You can try tightening 1/4 turn at a time. Keep count so if that doesn't fix the problem you can put it back where it started. This is mentioned in the installation document.

For comparison I have the valve on my car adjusted to a lower pressure and it works every time in warm weather. Gus and I anticipated that some cars would require more pressure so we made our best guess on where to set the valve. The setting is done at the valve factory using factory test equipment for a certain pressure at a certain flow rate. It will operate at a lower pressure in the car because the pump has a very low flow rate.

After posting this I realized I failed to ask a critical question. Is the engine on when this happens? If not the system voltage will be lower and the pump could come up short on pressure as the RPM's of the pump are directly related. The owner's manual recommends engine on when operating the roof and this is why.

Please let us know how this turns out so we can correctly advise others.

 

Hey Walt. I am not sure if this is covered somewhere in the extensive research and postings that were done by you and Gus (or Gus an you) but is there some small summary chart that you could provide here that maybe includes:

(1) maximum pressure in system without your valve installed (1,600 psi?)
(2) maximum pressure in system WITH valve installed (900 psi?)
(3) specifics for the adjustment procedure you are talking about (e.g., eacj 1/4-turn clockwise increases pressure by xx psi and each 1/4-turn counterclockwise decreases pressure by xx psi)

Thanks,

Doug

 

(1) maximum pressure in system without your valve installed (1,600 psi?)
The pump is capable of about 1650psi with zero flow. This happens at the end of roof down and during latch close and open.

(2) maximum pressure in system WITH valve installed (900 psi?)
I instrumented my car and saw that 900psi was the maximum that MY car requires, however this will vary according to the mechanical efficiency of each car. The stiffness of the roof fabric and the condition of the multiple moving joints in the roof lattice, and the condition of the hydraulic components, make for a lot of variables. The valve is factory calibrated for 1100psi at a high flow rate. The effective pressure at the low flow rate in the car is somewhat less than this. The valve is not snap acting so there is a region of operation where it is in various stages of open or close.

(3) specifics for the adjustment procedure you are talking about (e.g., eacj 1/4-turn clockwise increases pressure by xx psi and each 1/4-turn counterclockwise decreases pressure by xx psi)
Each full turn of the valve will adjust the pressure by about 250psi. The valve is spring operated so this is mostly linear. I advocate 1/4 turn adjustments because it is easy to keep track of. This is 60-65psi for each 1/4 turn. If the roof does not have enough pressure to "get over the hump" then a small increase in pressure should fix the problem. There is no immediate harm in adjusting the valve one way or the other but I do recommend keeping track (write it down) of what was done for future reference. My concern is that the valve gets adjusted relative to some other problem like a leaky lift cylinder.

The goal is to let the system operate at the lowest pressure possible. The main problem is at the end of travel on both ends when the controller holds the pump on when there is zero flow. This is when the pressure spikes and is clearly seen on the graphs that Gus posted on his site. We briefly considered a redesign of the controller but went with the relief valve instead because it was easier for everyone involved.

 

After installation my top opened and closed multiple times with no hesitations. After a week when the car sat idle, the top stalled after unlatching requiring a push to continue opening and closing smoothly. Succesive open/closes work without the push, however the next day the push is required again. I have adjusted the relief valve 1/4 -1/3 turn, with a resultant decrease in the push required. I'm going to wait before adding more pressure.
One question on the relief assembley, does the cover turn with the valve adjustment? If it does we could have turned it during installation in a counter clockwise direction.
BobF

 

Along with Walts comments on the lifts you should keep in mind that the two lifts and designed to pivot as it is applying pressure to the top to go up or down. The design is so that the angle and the pressure are working together. I am not sure that the movement of the lift might contribute to the slight hesitation in the roof operation.

 

Just to get back to you guys...seeing how the downside of increasing the pressure and having a hose let go far outweighs having to give my top a little help, I'll just let it be. BTW Gus, you were correct in that holding the top up button and letting the pump crank did raise the top today without any extra assistance on my part. Hesitated for maybe a two seconds. Thanks all for your efforts and help.

 

Good to know that you are up and running! If I could only get help on my s-type rear light problem! On the road again!!

 

My roof works great with no hesitation (with the kit) so not sure what others might see. There are lots of potential culprits for hesitation but I will reiterate that the relief valve is protecting and will do no harm.

The pressure is much lower during top down (gravity assist) so the relief valve will not operate then except at the end of travel when the control keeps the pump on for an extra second or two. Hesitation during top down is not related to the relief valve unless some other problem is causing the pressure to spike.

It is difficult to speculate what other problems can affect the roof system other than to say there are a lot of moving parts, all of which can have problems.