64 riviera drains battery in 3 to 4 weeks

[Guest Fred Barreiros]

Hello every one.

An older gentlemen in my car club ownes a 64 riviera  which is in  pretty good shape. I was recently talking to him  and he was anoyed about paying someone to fix his horn and find a battery drain! ~100 bucks later  and nothing had been resolved. So I told him I would try to figure it out. The horn was easy,  broken wire  some where in the stiring column! I put in a bypass wire from the horn relay to and a switch so he would have a horn until  we have more time to figure out where the wire break/bad contact/disconnect is. Also  removed  the new relay that  had been installed and re-utilized the  original relay setup. nothing wrong with it. He was happy to have the original  back.

 

The drain problem  is kicking my butt. The drain is small, only .250 Amps which still adds up by the end of the day.

 

1, with the  Ignition on OFF I disconnected every  visible connector under the hood, but the  drain remained!

2, Lowered the fuse box and located all  hot fuses, disconected one by one, same result.

3, no dome lights, trunk or hood bulbs on!

 

4, Did not get under the dash ( next time) but I was told the radio has been disconnected, so has the clock, neither one works!

5, It has no alarm.

 

 

My question is what the heck  could be drawing  exacltly  1/4 amp?

Thank you in  advance for any advice or suggestions.

 

Regards

 

Fred Barreiros

 

Legendary hot rods club member

[Beltfed]

Don't know if it's your problem but it was mine. Went through the whole trouble shooting thing as you and still had the problem. I found a leaking diode in the alternator. It was drawing 1/2 amp 24/7. I have a clip on amp meter which makes it easy to find problems. The alternator is a special one that couldn't be fixed locally. Cure...I installed a hi-current solenoid from a golf cart with a small hidden on/off switch. It also serves as an anti-thief device. Good luck.

[37_Roadmaster_C]

You are going about it in the right way.  I would try disconecting the alternator and the regulator next (alternator first).  As vsaid above, there could be a problem in the alt.  The next things I would check if there is still a problem is the clock and radio...  I know you said they were disconected, but until I see them disconected I don't believe it .  Anyway just keep looking and disconecting until the draw goes away then you will find the problem.

 

Robin

[Larry Schramm]

I am not sure that I understand what you mean when you say you are taking out only the hot fuses. 

 

I would put an amp meter on the battery cable and start pulling all of the fuses one at a time untill the draw goes away.  If the draw goes away then you know the circuit to go after.  There could be a back feed condition causing the draw.

 

On another thought, does the car have an aftermarket radio?  Or does the radio have any memory like a clock.  If so disconnnect the radio and see if the draw goes away.

 

Just the way I would look at it.

[tom_in_nh]

Quite possible that the electric headlight door motor circuit could be giving you issues.

Good luck.

[Larry W]

On my '75 Olds, the power antenna would retract whenever the radio, or the ignition, was turned off. When fully retracted, it would open its own power switch and cut power to the drive motor. One cold winter evening, the antenna didn't retract quite completely thus allowing the battery to discharge through the motor. I just unplugged the wire harness to the antenna while the mast was in the raised position. Problem solved. Also, check to make that the trunk and glove box lights go out when the doors are closed.

Edited August 26, 2015 by Larry W (see edit history)

[Guest Fred Barreiros]

Wow all good  suggestions. thank you. I did unplug the  Alternator, same issue. However, i did not disconnect the  charge wire!!! Will do that next, These alternators have the internal regulator right?  Even thought the  owner  said the radio and clock was disconnected sometime back I suspect it might not be true as well !  The  antenna motor is a good one, I'll have to check that. This car does not have the  clam head lights, i think thats what you guys call it.

As for the fuses, what I meant by cold is any fuse that has no 12 volts on it with the  ignition off. I only checked the ones that  had constant power (12V) on them all the time and they all  indicated zero current flow. Also checked for possible hood and trunk lighs on, none to be found!

The next time I'll start  at the horn relay and  dig deeper. Thank you for all the suggestions. Well he's happy to have a temporary horn fix

[Bill Stoneberg]

I believe the 64 does not have an internal diode.  It may be on the black box on the drivers firewall.  You may want to check you shop manual as I don't have mine with me right now.

I just remember because I had to replace the box because It could not hold a charge fort long periods of non running.

[TexasJohn55]

I think all alternators have diodes and rectifier bridge. That year would have had an external regulator instead of built in.