Another cab top troubleshooting question

[megerian]

1988 M491 Cabriolet.

Cab top starts back, immediately you can see that its out of alignment, because the right side is higher than the left, and the left side gets snagged as its trying to release from the top of the windshield. Stops almost immediately, and the Indicator light goes on. When I help the left side get disengaged and it starts moving up, its still stops almost immediately, just a few inches above the windshield.

Push forward on the switch, the right side does not seat properly, so it stops moving down, and the indicator light is still on. At this point, if I get someone to help me, I can start it back a little bit, then as the helper pushes the switch forward, I apply a little downward assistance to right side to get it to seat, then the front motors turn on, seal the top, the indicator light goes off, and I can drive the car.

This suggests that the front motors are working, and the sensor inside that detects that the cab top has sealed is working.

So is this just a matter of an alignment of the rear motors and cables? In the receipts provided by the PO, I can see a few years ago it was taken in for "realignment" of the cab top, and apparently no major parts were broken, since its showing labor but no parts.

If this is only an alignment problem, can I use the instructions in the owner's manual to disengage the transmission arms using the lugnut tool, then use the button to control the front motors, and just manually open and close the top until I get the realignment done? Some other posts refer to fully disconnecting the motors, to permanently go to a manual operation, and I was wonder about the value of that... perhaps to just stop the rear motors from running at all when the button is pushed?

Forgive the newbie - this care is new to me, and yes I knew about the cab top issues when I purchased the car. I wouldn't be opposed to manually opening and closing the top, since that seems to be a fairly popular choice.

thanks, Mark

[megerian]

Bump - and simplifying the question:

If the cab top is out of alignment, but the front latch motors are working, is there any downside to disengaging the transmission arms, and running semi-permanently in manual mode?

Do I have to disconnect anything else? My goal is to mess with as few things as possible, and have less to undo if I decide to have the top realigned in the future.

thanks-

[kkkarpuk]

Mark,
I've subscribed to the thread as I am also intrested in the outcome of this. My top is fine but with all the horror stories about snapped parts I may convert to manual as a preventitive measure. Good luck with this..
Ken

['89cab]

I ran mine for years with just the front latch motors. My motors or their cables got out of sync and I recognized the problem before completing the opening process which would have broken something I am certain. You don't have to have the Targa or old cab top handle latches.

After a new top installation the shop synced the motors, but I really don't trust anyone but myself to lower or raise the top.

As I recall your tire iron is the correct size to release the motor clutch through a plug above the back seat. Don't have my car with me so I can't check specifics, but it is a very simple process that can save you considerable money if you break a piece of the top frame. Look in your owner's manual for the process.

[megerian]

'89cab - I found the instructions in the owner's manual. Once you released those (one on reach side) did you run that way for a while without modifying anything else? thanks!!


BTW- I love that cartoon effect photo, where did you have that done?

['89cab]

I ran it without the main motor for years. Just raise and lower by hand. I would stand next to the driver's door and use the switch to release the front latches then lower the top. Raising is just as easy. When front rollers reach the latch mechanism, use the switch to complete the closure. I was perfectly happy to use the top this way. If I ever suspect any problems I will disconnect it again.

Thanks, the photo was tweaked with Photoshop or similar software. I did it several years ago so I don't recall exactly.