355 spider top question

I've had my '98 Spider for 8+ years now. Never an issue with the top functioning during that time other than having the roof bands replaced when I first bought it. The car hasn't been used in about 4 months. Running the engine today. I wanted to work the roof. It was slow to retract and the motor seemed to be louder than usual. In putting it back up, it went about halfway and stopped. It went the rest of the way with me assisting. I'm thinking maybe low hydrolic pressure.

Where is the reseviour ant what is the easiest way to access, check and fill?

 

Ratarossa has a video on roof problems which includes some details on the filling and bleeding of the system, but it makes reference to his website (and I couldn't find any additional data on his website).



Filling is around the 21:52 mark.

Haven't done this myself, and can't comment on the difficulty of doing this (or if there are any other easier ways).

 

Great. Thanks for posting the video. Exactly what I needed.

 

I fixed mine last year. Mine had the exact same symptom.

The fluid in the rams were thick like gel from age.

If the level in the reservoir is OK you will need to bleed the system as you may have air or likely the thin fluid has turned to gel.

Bleeding process is an easy job if you follow the procedure step by step.

FYI, make sure you service the system as the motor itself is big bucks if it burns out.

 

Same here.

When I got my car the fluid in the top mechanism was goo.

I followed a bleeding document I got on here somewhere the walked through the cylinder sequence to get everything purged.

Let me look around.............. and here it is: https://www.ferrarichat.com/forum/threads/procedure-to-cure-a-355-spider-roof-that-does-not-close-properly-due-to-old-fluid.316148/

 

Fluid was replaced about 8 years ago so not original. Hoping a you off will do it but prepared for a system bleed if not.

 

You just need to fill up the fluid with Mercedes hydraulic top oil. That stuff evaporates when you just look at it.

 

Good thing I haven't looked at it for 8 years.

 

Should the top be in a fully closed or fully open position to check the fluid level?

 

Fully open, when the ramps are fully retracted, and most of the fluid is in the reservoir.

 

Good question. There doesn't seem to be anything in the WSM about this.

There seems to be fluid on both sides of the primary rams, so, in theory, the quantity of fluid going into the cylinders on one side should be matched by a similar quantity being pushed out of the cylinders. The secondary cylinders seem to be different with fluid only going into one side (?) i.e. during roof closing. As soon as the motor stops, however, fluid may slowly drain back into the reservoir with gravity.

AFAIK, the primary rams are fully extended when the roof is open. The secondary rams are fully extended when the roof is closed.

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The windows are re-enabled during opening when the left hand primary ram reaches the bottom of the slider (full extension).

 

Thanks guys. We I go to top off this weekend, hopefully it will open.

 

Maybe you could let us know how much the level changes during opening and closing?

 

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Rams seem to all be push pull. I don't think position matters when checking level.

 

The hydraulic diagrams do show a return line on each secondary ram, but unlike the primary rams, the line is not pressurised. If there is any fluid on the other side of the ram, maybe it's just to allow for seal leakage.

I've redrawn the hydraulic diagram to show the proper orientation of the rams.

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Full sized diagram here:

https://www.dropbox.com/t/FCPF4LY9mkDhQkSm

I rechecked my primary rams a few minutes ago and confirmed that they extend to drop the roof.

 

Here is my data point.

My 1996 Spider was parked for a long time with the roof down. It refused to go back up. So, I pulled the center cover open and it was very clear that the fluid level is below minimum. A syringe fill method was deployed and when the fluid level is at its maximum point, the roof was activated and it worked again to go up into a closed position.

 

Mine is in the up position. I will measure when it is up and then see if I can get the roof to go down. I will measure again when down before filling.

 

If there isn't fluid on the "return"side of the secondaries then, since they are extended when the top in closed you would expect the fluid level to be below the max line (secondaries are full). When the top is down, and the secondaries are retracted (secondaries empty), the fluid would rise to the max level. If the level is constant, top up or down, then there must be fluid on both sides of the secondary.

 

I'm not completely sure I understand what you're saying, but note that when the roof has completed its up cycle and the motor is turned off, the "F1" solenoid valve is de-energised and fluid may be able to drain back into the return lines from the pressurised side of the secondary ram cylinder/s. I guess it would depend on the orientation of the ports on the rams.

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With power off the roof system, the grey section of the valve is active. i.e. the #3 port is connected to the #2 port.

 

All the fluid in the secondary cylinders should be forced back into the reservoir when you manually pull back on the roof during the beginning of the open cycle. Theoretically, this should show the maximum level possible in the reservoir (i.e. the time it would take for fluid to flow naturally back into the reservoir with the roof closed wouldn't be a factor).

 

What I am saying is that when the top is open there would be no or very little fluid in the secondary cylinder. But when the top is closed (closing) and the secondary extends it fills with fluid. I can't see how fluid would then be allowed drain back with the secondary still extended since the fluid would have to be displaced with something (air?). Even if it did drain, at some points in the cycle the secondaries would go for empty to full and the level in the tank would have to reflect that change in volume. If extended secondaries did drain eventually, then watching the level during top operation open/close/open/close should reflect the filling and emptying of the secondaries before they could drain. I'm thinking that the solenoid opens when the top opening begins to allow the secondaries to expel fluid from whatever causes them to retract.
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Good point. Air might take a long time to find its way up to the cylinders (assuming the seals are good and not letting in air on the other side of the piston). I guess with the roof latched closed the pistons are fully extended and they can't be sucked back with the suction of the draining fluid.

By "open", do you mean in the return/drain mode? If so, yes, the solenoid is only energised during the final closing stage (otherwise it's in the drain mode). I assume you mean by "whatever causes them to retract" you're talking about manually pushing back, the strength of the elastics, etc.

 

Yes, and yes.

 

Probably a good reason why my top is giving me trouble. Even with the car on a slight angle it's easy to see that the fluid is way below the minimum. I was going to open the top first to see the difference in the levels but at this point, I think it is best to fill it first.
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Well I braved it and opened the top with a little assistance. You can see with the top fully open, the fluid is actually lower in the reseviour. I will give it 30 minutes to see if it drains back down.
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