Battery sizing
The bottle has a stamp on it that signifies the type of plastic. I forget what it is, but I'm guessing polypropelene. This stuff is hard to glue no matter what one uses.
The flip side of that is ABS. That stuff can be chemically welded with ABS pipe cement available from hardware stores.
The flip side of that is ABS. That stuff can be chemically welded with ABS pipe cement available from hardware stores.
TECH Enthusiast
Joined: Nov 2011
Posts: 587
Likes: 12
From: Connecticut SE shore
....With the low amp/trickle chargers, it seems that you need to get the initial surface voltage pretty far above 12.65 for a complete and lasting charge. Normally when my automatic charger completes, the voltage will be somewhere close to 12.8-12.9 volts, and then drop off to 12.6x over the next 24 hours if the car is not touched. At that point, it'll stay over 12.5 for 1-4 weeks depending on the age of the battery.
I really can't complain about my current Delco 75 PG, it's still doing extremely well for a 6+ year old battery. I'd like to see how long it'll go, but like you said I'd hate to get stranded some time.
I think the epoxy fix you suggested would work well in a situation where it's still just a fracture and not yet fully broken. It might even work for a more complete breakage if applied well. I also wonder if JB Weld might do the trick for this.
I really can't complain about my current Delco 75 PG, it's still doing extremely well for a 6+ year old battery. I'd like to see how long it'll go, but like you said I'd hate to get stranded some time.
I think the epoxy fix you suggested would work well in a situation where it's still just a fracture and not yet fully broken. It might even work for a more complete breakage if applied well. I also wonder if JB Weld might do the trick for this.
When trying to epoxy my battery front lip it cracked completely off when applying pressure to seat it tight (ie the opposite direction of the orig crack). So be careful applying pressure in either direction. I was probably applying 15-25 lbs of force.
I just replaced my battery tray today because of the cracked lip. I was very careful installing the battery and only snugged the hold down bolt. I can see now why these crack. As I was tightening the bolt, you can feel the battery push slightly forward against the lip. It always has pressure pushing against the plastic, plus the normal bumps and vibrations from driving take there toll. Maybe GM should have put a metal tray there and stuff the overflow tank next to the giant washer reservoir!
TECH Enthusiast
Joined: Nov 2011
Posts: 587
Likes: 12
From: Connecticut SE shore
And having seen a lot of rotted and peeling paint on original battery trays from my 1968-1970 Mopars, it was a good move to change to plastic. You'd always find battery acid spotting on the driver's top inner fender....always. I'm sure the engineers figured a plastic tray + coolant reservoir was both a weight, cost, and space savings. And of course being able to sell another $60 battery tray/reservoir. There was nothing but open space around those old Mopar battery trays. Those trays cost about $30 today. And if you want, you can always clean up the stained original ones and repaint them for about $5. They didn't have any reservoir bottles back then. Excess coolant went to the ground. 
Teching In
Joined: Apr 2015
Posts: 47
Likes: 0
From: Upstate NY
As stated above, group number has to do with the physical case size of the battery, and these cars are group 75 from the factory. My Nova takes the larger group 78 battery, and frankly I wouldn't want the hassle of trying to stuff that into the F-body mounting location.
I have no idea what group size a '99 GP takes though.
I have no idea what group size a '99 GP takes though.
