I Found A New Battery Alternative

I did not know my 1986 QV coupe would not generate enough voltage at idle to run itself with a weak battery. The battery would not engage the starter, but ran the windows up and down so I pop started the car down the drive and drove for a six pack figuring I would leave the car running. But a block later the car just died.

The neighbor gave me a jump and car started right up but died again when the jumpers were removed. We did it again but once started I kept the revs up and got home ok. Then removed the battery from the top by taking out the small front trunk quarter panel that is just above and to the rear of the battery.

Then visited AutoZone for the biggest baddest version of the existing battery in deep discharge variety. [My car has a voltage leak someplace so I turn the battery switch off. But sometimes forget and gues what? Bad battery made worse after four or five days to drain down.]

They quoted something like $168 but did not have one in stock. So I asked for a marine version which they had on the shelf. It is Duralast 24MD-DL with marine cranking amps @32F = 685; cold cranking amps = 550; 85 Amp Hours. Not sure what all those numbers mean but to me a marine battery simply means it can go dead without dieing.

It is larger then the one it replaced which means a couple of things. First, it is 3/8 in deeper front to back and although it fits in the battery box it covers up the tie down screw hole. Turns out mine was not being used anyway but the battery is taller as well and fits snuggly against the reinstalled trunk quarter panel. Though you can not get to the back installation screw so it is just dropped into the hole.

The most difficult thing was to fit the trunk quarter pannel back into possition. It came out with a small struggle but going back in was a *****. I even removed the windshield washer tank [it just pulls out of its clips] and also the air horn pump. That is the large can-like thing on the passenter side of the trunk area with two rather large hose fittings. One of them goes to the finger size hose that snakes into the front of the car. I don't know whether is sucks or blows. Should have paid more attention when I took it out.

The battery change made more difference then any of the dozens of battery changes I have done over many decades. In fact, the passenger side window has been possitively resuretected. It has been dead for an entire year but had not quite gotten the word. The drives side window is now actually good.

But the windshield Wipers? Wow. They only worked when the windshield was wet. Which is when you want them to work, of course. But now they actuall swipe back and forth with something approaching tentative authority.

And the starter? Its only six month's old but now reacts to the key and turns with authority like it is a different device.

Thats my story for your consideration.

Rapalyea

 

You are the second person to mention a possibility of this sort. The other guy said it could be a diode in the alternator itself. However, I am training myself to always turn off the battery and now have a deep discharge marine unit just in case.

The battery seems to charge adequately during routine driving and is full strong after a days driving about. But at least now I have a better idea about the whole thing. I wil log this in my car book for whomever ends up with the car after my future demise, should I not turn out to be immortal.

 

I actually bought a 10 amp multimeter today and will start looking. One possibility has already been eliminated. When I removed and cleaned the various terminals and the ground strap I found what seems to be a hot wire with in line fuse to nowhere. May be for the old theft device? Thats one reason I bought the multimeter.

Your observation on the marine battery are well taken. However, the little 8 Cylindar engine is not exactly a fuel dragster and the Starter spins rather easily. But if the battery it goes bad I will get a more conventional deep discharge version. This one only cost $89 and with all the terminal cleaning and what not it spins the starter with modern car instant enthusiasm.

Even the windshield wipers now work

 

Starter is stronger then ever before as are window and wiper motors. And the battery only cost $89 anyway. Also the battery states right on it "marine cranking amps @32F = 685".

Perhaps we have different specs; I have had boats for many years and have always thought of marine batteries as simply deep discharge tolerant. I have a small 21ft pontoon boat and next time I am over to the marina will ask.

 

Battery drain is now at 0.08 amps so disconnecting the strange in line fused hot wire might have been the problem. Time will tell.