Having delved deep into the mechanics of the Spider roof I have concluded that most problems are relatively easy to fix as long as you are able to identify which componentry is at fault.
I suspect from reading this forum that the vast majority of problems are caused by leaking hydraulic lines, or failed flap motors. Similar problems affect all other powered roof systems - and some more than most. For example, the Vauxhall/Opel Astra Twintop (folding steel roof) is notoriously prone to wiring breakages inside the bootlid loom sheathing (a bugger to locate) and stripped nylon gears on the flap motors.
Identifying which componentry may be at fault is a matter of checking everything thoroughly.
Read the handbook on how to raise the roof in event of failure - remember that to manually lower the roof is the reverse of this procedure.
The roof is controlled by a separate microprocessor unit located in the hood storage well behind the passenger seat. It drives a hydraulic compressor located on the other side of the car - behind the drivers seat under a thick rubber soundproofing cover. The compressor feeds a number of hydraulic lines (each of which is numbered). There are two hydraulic lines per hydraulic ram - to provide both extend and retract function. The order of operation is controlled by the microprocessor via solenoids on the side plate of the unit. These solenoids will get very hot if the unit strains to operate for any reason and the microprocessor will shut down operation to avoid overheating.
On pressing the hood switch the operational sequence seems to run as follows (please let me know if you can improve on the sequence): words in italics are Alfa's own nomenclature. "E" and "H" refer to electrical or hydraulic operations
- Button pressed E
- Windows drop slightly each side of car E
- Rear end of hood (bow) lifts H
- Hood cover panel (top cover) unlocks H
- Hood cover panel lifts vertically H
- Front edge of hood over screen unlocks H
- Flaps move to vertical position E
- Front edge of hood lifts, hood folds and drops into storage compartment H
- Hood cover panel lowers and locks into place H
- Windows lift to fully up position E
- System beeps to confirm end of sequence
Stages 6 and 7 seem to be simultaneous, or at least very hard to differentiate by simple observation.
At the end of each stage an electronic sensor signals the microprocessor that the operation is complete.
Without this signal the microprocessor will assume the operation has failed.
Hood raise operation is the reverse of the above process.
If at any stage your hood starts to raise/lower then fails in mid-sequence you should investigate not only the operation the roof was performing at the time the dreaded beep alarm sounded, but also the operation which follows it.
I will be posting a "how to" on replacing hydraulic pipes soon, but in the interim here are a few hot tips:
- DON'T PANIC. Roof failure does not automatically mean repair bills in the £0000s. The vulnerable components in any roof system are those which are folded during operation. This includes wiring as well as hydraulic lines. The chances of a microprocessor or hydraulic pump failing are slim - possible, of course, but very slim. Similarly, hydraulic rams are usually very robust and good for several thousand operational cycles before needing new seals. They also have the benefit of it being obvious to spot in the (unlikely) event that they spring a leak.
- Most hydraulic failures will be caused by the lines being pinched inside the hood framework. Sometimes this will not spring an obvious leak, but will cause the inner sheath to leak fluid into the outer sheath. Sometimes (but not always) this causes the outer sheath to blow open under pressure, and such failure may occur some distance from the pinch site.
- Hydraulic leakage results in inefficient (slow) operation. In turn this risks overheating the pump/solenoids - and the microprocessor's failsafe circuits will eventually cut the power to prevent damage.
- If you have to lower/raise the roof manually you will have released the pressure valve on the hydraulic pump by pulling the cable located in the storage locker behind the driver's seat. The only foolproof way of resetting this is to open the rear cover to gain access to the pump and feel around the underside of the unit for the operating cam. This has to be pushed back (towards rear of car). If you do not do this you will hear the pump whining but there will be no movement of the roof parts.
- A roof which operates more and more slowly is probably suffering from a hydraulic leak
- Always look out for more than one fault. It is not uncommon for a flap motor to fail as well as a hydraulic line.
- As stated, the hydraulic pump solenoids will get very hot if the unit strains to operate for any reason and the microprocessor will shut down operation to avoid overheating. For this reason it is a good idea to disconnect the battery if you are going to work on the roof for any length of time.
- New hydraulic lines and compressor oil are all inexpensive and available from Chris Porter at Welcome To Cabriolet Roof Hoses.hydraulic roof hoses manufactuer. He states that he never supplies any hydraulic lines for the Spider other than 31 and 32 - which both run from hydraulic pump to front roof and are therefore susceptible to pinching in the folding metalwork.
Pictures of typical pinch damage and blown pipework are now in the Image Gallery.