I have simular problem to the one posted by "ptroxx"

I have a 68 427-400 that I have had since 10-75 and has always had a small battery drain so I have had to jump it or charge it for a little while if it hasn't been started for a few weeks.

My brother in law has been using it in parades with his daughter and it has been running hot so he put an electric fan in it hooked directly to the "Batt" terminal on the alternator. Now the battery is killed overnight, ( I replaced the battery with a new one) even with the fan disconnected. The car will run at fast idle with the battery disconnected so I assume the alternator is still good. I have a heavy drain with a test lamp or ammeter. The car's ammeter is on "0" when the ignition switch is off, slightly neg when on and indicates charging when running

When I touch the neg battery cable to the battery I get a spark and a sound from the dash like a relay regardless of key position. I am thinking the ignition switch is bad. I am not sure where or what the relay sound is. Does anyone know how much trouble it is to replace the ignition switch or have any other ideas. The fan has been disconnected so that is not the problem now.

I'd appreciate any ideas

Thanks

 

Could be a relay you hear or the wiper door solenoid.Lets get this out of the way first.On your test light- hook the aligator clip to a manifold bolt and then touch the probe end to the wiper moter case and see if it is hot.If it is -the 14 black at the starter is on the pos. term instead of grounded on a bellhousing bolt.This will create a drain on the battery.

 

Thanks, I'll try that, but the heavy drain is recent and nothing has been done to any wiring except the fan. However, the wipers did stop working for a while while I was trying to sort this out. They work fine now the fan is no longer an issue.

 

The heavy drain was recent.. But you did say-always had a small battery drain so I have had to jump it or charge it for a little while if it hasn't been started for a few weeks.


SO it has been draining. The 14g wire fromstarter is also something to look at..

Good luck.

 

Thanks
I don't have any current flow from the wiper mtr to block, but when I just checked the current from the neg cable to battery I only got 6 Ma, insteat of pegging the 600 Ma scale last night. Only tiny spark between cable and battery, like radio memory etc. When i turned the ignition switch on and touched the cable to the battery I got the same relay sound and didn't get it with switch on off position. Last night it was doing it in all positions. This is why I was thinking it could be switch related originally.

 

With a 68 (I have one) there is a very high probability that the wiper system is causing the battery drain.

First of all, by design, the battery will drain if you leave the wiper override switch in the on position. This is the little *** under the dash that freezes the wipers on the windshield. You would use this switch properly to change your wiper blades. There is a warning on page 20 of the owner's manual that leaving this switch in the on position will drain the battery, even if the engine is off.

The wiper motor will have a hot wire to it even when the engine is off (!!!!). Turning the wiper switch on provides a ground to the motor which turns the wipers on. This assbackwards system makes it very easy for the wiper motor to drain the battery, even when the engine is turned off.


Easy way to test if wiper motor is the source of your battery drain is to pull the wiper fuse. My fuse has been out for 8 years!

 

Thanks, that might be the problem. For some reason I have 1969 owners manual, not a 68 and I don't see a mention of the problem. A lot of cars have quirks in the first year of production and I think the 68 is at the head of the list. In any event, after a day and a half I still only have a slight, 6 ma drain that I'll try to sort out later, but there is no major drain and the override switch could have been the problem.

 

in 1968 I believe the largest alternator you could get was about 63 amps(somebody correct me if I'm wrong); and it also used an external voltage regulator. When I had my original alternator, it was always marginal.
I replaced my original alternator with a 12SI internally regulated 94-amp alternator. That worked out really well, until I got an electric fan. I have now installed a CS-144 ~140 amp alternator; had to get it to support the electric fan.
I seriously doubt that the original alternator can support the operation of an electric fan. Assuming you don't have some sort of short, you may want to check the battery terminal voltage; both when the fan is running and when it is not. That will let you know if the alternator is capable of maintaining voltage.

 

I'm having a similar problem with my 73. When I connect the battery negative with the test light, a relay sound from under the dash can be heard. I've isolated it to the brake circuit, but still can't figure out the ticking. I've removed the hazard flasher (brake circuit runs to it) and the steering harmonica connector, (key reminder buzzer is on the circuit) and it still clicks and shows a draw. Any ideas???

 

Disconnect the 3 wire plug that goes to the wiper motor. It's the plug with the red wire in it. If the draw goes away your motor has gotten hung and needs to be recycled. I just rewired my 68 completely and when I hooked up the positive battery cable for the first time, big spark!
Knowing there was nothing hooked up yet as all of the interior is out. I started checking and the wiper relay was part of the draw. When the wiper motor got unplugged the draw went away. I had to take out the wiper motor, pull it apart and unlock the main gear that was jammed. Evidently when I put power to the car for the first time, the wiper motor partially turned and locked up because the ratchet lock inside was not retracted. The motor locked and wanted to turn but couldn't.

 

no dice with the wiper motor... mine is still working fine. Still can't figure out the relay tick in the brake light circuit though....

 

No other ideas??

 

Have original owner 68. I have experienced a battery drain problem many years ago. The center compartment is illuminated when you open it whether the key is on or off. My light was staying on 24hrs because the closing the door would no longer turn off the light. Fixed that, just disconnected 12 volts to the light. Have not really missed using it.
One day cleaning the my 68's dash, accidently moved the wiper switch to on. Turned it off. A few days later the battery was dead. The car was not used during this time. On my 68 I learned that if the wiper switch is turned on accidently, the only way to stop current drain is to just start the car and cycle the windshield wipers. Don't know how accidently turning on the wiper switch with the cars ignition not on makes a drain on the battery but it does on mine. If I am not going to drive my car for a week or more, I just reach underneath with a 5/8 inch wrench and disconnect the ground cable from the frame. Easy to reconnect and start the car in about a minute.

 

This is great, I've had this exact problem with my 74 since I've owned it (5 yrs) and it has always baffled me. I actually gave up looking for it and installed a battery quick disconnect. Thanx to this posting I found my problem. I tested the wiper motor housing and found it was hot. I moved the wire on the starter to the ground and the wiper housing isn't hot any more. I also checked my center compartment light, just to make sure, but the bulb was turning off when I closed the lid. Thanx for all the helpful advice, even though this wasn't my posting.

 

My wiper appears to be wired correctly.. (case is not hot, it is grounded). Drain is small, (dim on the test light) and definitely in the brake circuit. Disconnecting the harmonica connector should eliminate a bad signal switch. (disconnecting did not change the draw) Removing the courtesy fuse eliminates the clock from things (and has no effect on the draw from the brake circuit) I still get the relay like tick when I complete the brake circuit and can't find the source of the sound. I'm suspecting this is the cause of my problem and the original poster's. Anyone?????

 

My 68 has always had a slight battery draw which will drain the battery over a 2 week period and I've always blamed it on the clock and radio memory. I just disconnect the pos cable at the battery when not in use. I also get the "click" when the battery gets hooked up.