bigfun64mo

I recently bought a 72 cutlass convertible. The top did not work. I replaced the switch and hoses. Now the top goes up and down. But, it runs for about 10-15 sec. Then cuts out for 20-40 sec. Then it will run again for 10-15 sec. etc. Is there a relay that needs replaced? I have looked in my maint/body manuals. I cannot find anything.I need some direction. HELP please!!

Lady72nRob71

Welcome BigFun!
This sounds like the circuit breaker cutting out.

The breaker on my 72 is in the upper left of the fuse block. I think it is a 40 amp. My 72 has NO relay like some other years.

It is possible that your pump motor is overloaded or is going bad.
How fast does the top move? How loud is it? How much do the courtesy lights dim when you run the top?
My top raises or lowers in about 10-15 seconds and is the loudness of a standard cordless drill.

If the motor is okay, your breaker may have been replaced with a smaller capacity, OR it may be bad and is opening before it should.

bigfun64mo

Thanks for the help. My next question is, if the circut breaker is tripping, does this reset itself? I am not resetting it. I did think that it could be the motor overloading. My problem is I am not very good with electrical issues.

Lady72nRob71

Yes.
In a circuit breaker, the heat generated inside it due to overload trips it. When it cools (in about 30 seconds or so), it resets itself.
A fuse blows at first overload and would need replacing.

bigfun64mo

Again, Thank you!! Gawd, more work under the dash. Ugh I am too old and fat for this. At least I have a starting point. I have a Fisher body manual for this year, the power top had not been used in year or two from what the guy told me. It had no fluid in the pump. I pulled the pump out, primed it, re-installed. I got it filled following the manual. There was a lot of air in the lines because they were new that I worked out. I will let you know.

redoldsman

I think Rob nailed it with the circuit breaker. I have a 72 Cutlass convertible also. The only thing I ever had to do was replace an o-ring in the pump when I got the car since I could not keep fluid in the pump. The circuit breaker is not one you push a button to reset. There is thermal strip inside that interupts the circuit when it gets too hot and as Rob said, cools down and then makes contact and completes the circuit again. Your problem sounds exactly like a circuit breaker heating up and then cooling down. I bet somebody has replaced it with one that is too small. Easy fix and you won't have to stay under the dash very long. Good luck.

dwsshay

mine on my 70 delta 88 is also doing that,does anybody know where the circuit breaker is on it one on fuse box is for flasher i dont know what the one under dash is top still worked when i took it off,thanks

bigfun64mo

Mine was in the accessory fuse spot. pulled it out it looked ancient. replaced it. no problems since. Thanks guys.

lovinmrv

One day, my top just stopped working, luckily with the top down.

I assume the issue is electrical. I have attached 2 pics that show the fuse block. I also assume that the relay is one of the doohickeys in the top left of the fuse block. The topmost fuse is a 20 Amp.

So, which dohickey do i replace, the round one on top or the rectangular one underneath?

Thanks

MDchanic

The big round thing is your 4-way flasher.

The rectangular thing under it, labeled ACCY PWR RELAY is a circuit breaker for the accessory system - windows and the like. I am not sure whether it also does the top, but I think so (you could always check your manual). The other guys will know.

- Eric

kens69olds

Can someone point me at the Power Accessory Relay on a 69 Cutlass? I've heard it might be in the engine area firewall. I can't seem to locate it. Thanks.

brown7373

You guys haven't lived until you deal with the convertible top like on the 64 T-Bird I used to have. It had more relays, switched, solenoids and deck screws that Carter had pills.

Texas69

For a 69 Cutlass it is under he hood, driver side firewall between the brake booster and the fender. Rectangular box about 3/4" x 1 1/2". A convertible will have an orange power lead running from it through the firewall to the power top switch

MDchanic

That's his top circuit breaker.

There is no top relay in that car.

- Eric

kens69olds

Thanks Texas69 and Eric - I swear I looked thoroughly and couldn't find it. I found a relay that had a couple of wires going to it just above the master brake cylinder, and when I unplugged the wires the top still worked (well, for the standard 5 seconds before it cut out).

Can you guys confirm this is the circuit breaker I'm looking for under the hood?
http://www.ebay.com/itm/64-74-GM-30-...5a28be&vxp=mtr

Thanks a ton!

Texas69

That unit looks like what sits to the right of the master cylinder on the firewall. I am not sure off hand what that thing is above the master cylinder, but it is not related to the top

There are different amperage units. I believe our is a 30A, but you should confirm.

droldsmorland

Make sure the grounds on the pump and in its circuit (if there are others) are clean and tight.

MDchanic

Yup, that's it.

- Eric

kens69olds

I found the circuit breaker and pulled it off. It was covered in so much muck I couldn't find it right away. Anyway, everywhere online where they sell these, they say 30amp but engraved on the one I pulled off my 69 cutlass it says "12v 40a" - which leads me to believe it's 40amp?

Anyone know for sure these are supposed to be 30amp?

kens69olds

According to Original Parts Group, it's in fact 40 amp breaker for the Cutlass. A lot of sites sell a 30 amp for this car for some reason. Maybe it works just fine, but I think I'll go with the 40 amp one from Original Parts Group:
http://www.opgi.com/cutlass/1969/ign...mmers/C241032/

Texas69

The spec for the breaker is probably in the wiring diagram in the service manual if you wanted to confirm.

kens69olds

So I replaced the circuit breaker and the problem persists. When operating the convertible top switch, it runs for about 10 seconds before it cuts out. Then after waiting 30-40 seconds, it will start working again, but only for another 10 seconds or so. I'm guessing the switch or motor is bad. Is there any way to diagnose which it is before I spend $250 on a new motor? Any help appreciated!

69 Ragtop

Here are a few ideas:


You can jumper across the switch contacts to run the motor. That will either implicate or eliminate the switch.


It is possible that the motor is drawing too much current on its own, causing the circuit breaker to cycle.


It is also possible that the joints in the top are not lubed, causing additional friction, which will cause the motor to work too hard and draw too much current.

kens69olds

Bob - thanks - how exactly do I do this?

69 Ragtop

Unfortunately, my Cutlass is under a tarp that is tied around the undercarriage, so I can't be specific. You need to get to the wires behind the switch. Of the 3 terminals, one is up, one is down and the middle one is +12V. Jumper the middle terminal to either side terminal to make the top go up or down. I have a feeling you still will have the problem because the system is drawing too much current, and it is overheating the breaker.


Disclaimer: My experience is on a '68 GTO. I am 99% sure what I have presented here is accurate, but if not, someone please tell us.

Mortimer

Just got through rebuilding my top pump and replacing the hoses. Cost is cheap. Pulled the motor and disassembled. Full of crud and the electric motor housing was full of oil and crud. Cleaned up the reservoir, pump and motor. Took some time to put the armature back in because the brushes are hard to hold in place while re-installing the armature. Replaced with new hoses ($100) and new orings ($2). Flushed the system with Dexron III tranny fluid. Filled and bled air from the system. Works like new, again. Takes a bit of time but well worth it.

69 Ragtop

Fixed! YEA!

ddd777

I am thinking that I have this problem (or possibly a bad switch) so I am trying to run down all of the possibilities.

Question: Looking in the Oldsmobile 1972 Shop Manual at the electrical schematic for A Body cars, the 40 Amp circuit breaker in the fuse panel doesn't seen to be hooked up to anything, and I find no mention of a convertible top switch. (see green circle in attached image)