1976 Eldorado convertible top suddenly stopped working

[Mihai Tarţa]

Hi!
In September, just after I bought the car and put it away for the winter, the top worked just fine. I probably opened and closed it 4-5 times.
This week, I had to attend a wedding show and I wanted to display the car with the top down and the top won't even budge. I'm pretty sure that there's no  power going to the motor(s) for some reason (fuse, switch, etc.) because when I press the switch there's nothing but dead silence.
I'd like to sort this out somehow and the first thing that came to mind is to check the fuse.
I looked it up in the service manual and I noticed that it has a circuit breaker instead of a fuse. Can it be reset somehow, or does it need to be replaced?

Thanks !
Mihai

L.E.: It's not the circuit breaker, because the power seats, horn and power door locks work and, afaik they are wired to the same circuit breaker.

[cwcinps]

When I had an issue I found the Troubleshooting guide on the website of Convertible Top Service out of San Gabriel to be very helpful.  Those switches are well not the highest of quality.  The top relay (single purpose relay) takes removing the back seat but easy enough to test.  if there is no clicking at all then hopefully you have a meter to test power.  I think it is bad forum to put the URL here but a quick Google with convertible service and San Gabriel you will find them and then look for scissor top and then the troubleshooting guide. 

Best of Luck,
Chris Caufield
76 Eldo
57Cpe DeVille

[Mihai Tarţa]

Thanks!
I've found the manual.

Is it safe to remove the drive cables and operate the top manually?
If I want to test the motor and relay, do I also need to remove the back rest of the back seat or only the seat cushion?

Thanks,
Mihai

[The Tassie Devil(le)]

G'day Mihai,

Firstly, if you cannot hear any clicking from the front when you press the switch, either way, I would go looking for a problem with the power supply to the switch.   The wire could have come off the switch.

To remove the rear seat to gain access to the motor and relay, first you need to "un-clip" the seat base by pushing rearwards on the bottom of the seat base, about a quarter of the way in from the outside, to release the base from the two floor-mounted clips.

Then to release the seat back, you have to unbolt the outer seat belt bolts as these hold in the seat back retaining brackets.

Then you have to carefully lift the back, to clear the top hooks.   BUT NOTE... If you have the Fibre Optics still in place, you will need to unfasten the bracket from the top of the seat back when you have the back high enough to access the screws.

The Relay can then be tested for power, etc.

I wouldn't recommend undoing the cables unless it is an emergency, as you could possibly put the system out of sequence when you go to put them back on after manually cycling the top.

I had a similar problem with a '71 down here, and it turned out to be the power supply terminal on the relay that feeds the motor had come loose and the only way to fix it was to re-peen the rivet holding it to the relay.

It is possible to operate the top manually, but it required a lot of physical strength to put it up, and down.   You are working the drives and motor as they weren't meant to be.   How do I know this?   The owner of the '71 had the problem with the relay twice and the top was down both times.   The electrical fault initially fixed itself the first time when the wire was bumped, and the second time, bumping wouldn't fix it, but I had to repair the broken seat back after he forgot about the seat removal procedure.   These poor quality masonite seat backs are easily broken.

Bruce.

[Mihai Tarţa]

Thanks, Bruce! I'll pay attention to that.
This is the nicest forum ever, full of kind, helpful people.
Thank you! 

[austingta]

A couple of things: this happened to my 66 last year and it was the motor / pump unit. There was no noise or clicking at all. There is a service which I used, and highly recommend. My top works perfectly again.

http://www.topmotorrepair.com/

You can raise and lower the top without the aid of the motor, but, after ytou disconnect the arms from the pump / motor assy., you need to have one strong person on each side of the car. The top is heavy!

[TJ Hopland]

Frank, the top on the 71-76 Eldos is a completely unique mechanism that I don't think was ever used before or after.  Its completely mechanical.  Its got a power seat like motor behind the rear seat that drives gear boxes at the base of the arms via speedometer like cables.

I didn't check the link but if that is the same guy I had do a top pump for me he also does the motors and possibly the gear boxes for the Eldo tops. 

The motor and relay design is a little odd also, this was a drawing for the power seat motor from the same era that I modified to resemble the top circuit since the top circuit does not seem to be published on its own, its only shown on the big overall drawing so its a little hard to follow.   Because of the unusual design there are more failure modes than say a window motor.  Apparently one of the failure modes of the relay just stresses the heck out of the motor and basically burns it up. 
   

[austingta]

He does rebuild the scissor top motors, and speaks to the importance of and sells the relay as well.

[76eldo]

I would check the relay first. The switch is hard to get out and easy to break.
If the switch feels ok it may not be the issue.
If you get to the relay you can use a meter of test light to see if the switch is sending 12 volts to the relay.  Keep on mind it's a hot circuit not controlled by the key.

Brian

[The Tassie Devil(le)]

With regard to the relay, when I found the problem with the '71, the power feed wire showed 12 volts to the relay terminal, but it still wasn't working to send voltage to the forward and reverse wiring of the motor.

Opening the relay showed that there was no voltage between the pin rivet and the internal piece that fed the relay internals, which included operating the magnetic field coil.

It took a carefully placed punch, anvil and hammer to re-crimp the rivet which completed the circuit.

Then everything worked well.

Bruce.

PS.   I found the problem after I had stripped the motor, re-lubed it as I found nothing wrong (tested it on the bench) and reinstalled it.   Electricity is a funny thing at times.

[Mihai Tarţa]

Problem found!
I removed the rear seat and I found that the connector which feeds power from the switch to the relay had fallen off. As simple as that.
I want to thank everyone for the feedback and tips. You were all very helpful.

[The Tassie Devil(le)]

Congratulations.

I do hope you "tightened" the clip before putting it back on.   You must have some really bumpy roads to cause the wire to slip off in the first place.

Bruce.

[Mihai Tarţa]

We do have some pretty bumpy roads over here, but I suspect that whoever worked on the car before I bought it, didn't push the connector all the way in on the relay. I put it back and it seems like it's sitting pretty tight.

Mihai

[Mihai Tarţa]

Also, if you happen to have some recommendations on maintenance of the scissor top mechanism, specifically lubrication (what product in which spots and how often) they would be very much appreciated, as I've never owned a convertible before.



Thanks,
Mihai

[The Tassie Devil(le)]

The Shop Manual describes where to lubricate the hydraulic folding top at the end of that section, but describes the lubrication for every separate operation of the Scissors top in its' description of the assembly process.

Your best investment is to obtain a Fisher Body Service Manual for your car.

Don't forget a Workshop Manual either for the mechanical, electrical and chassis parts.

Bruce.

PS.   Don't over lubricate, as there is nothing worse than drips.

[Mihai Tarţa]

I have the Fisher Body Manual, but I must have missed that part. I'll take a closer look at it.

Thanks,
Mihai

[Mihai Tarţa]

I still can't find the info on lubrication in the manual. Do you by any chance remember where exactly can be found?

[The Tassie Devil(le)]

All I have is the '71 and '72 Fisher Body Manuals, and the Convertible Top is covered in the back of Section 12.

I am off to bed now, seeing as it is after 10.30pm down here.   If you still can't find it, I will scan the section and send it to you.

Bruce.

[Mihai Tarţa]

If it's not too much trouble, I'd appreciate it.
No hurry though.

Thanks,
Mihai