The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 47-55.1 Parasitic drain

**mr48chev** · 12-30-2020, 08:46 PM

Do this before you go much further. Take your multi-meter and check across the top of the battery in several areas.

Connect the positive wire to the positive post and take the tip of the negative wire and touch around on the top of the battery to see if you have power draining off across the top of the battery in any dirt or moisture that might be there.

When I was teaching auto mechanics one of my student's truck would have the battery go dead in two and a half hours sitting in the parking lot. We would jump it, run it around to the shop and stick the charger on it and charge it and it would start right up and it charged right on the money. About three days of that and we made it a class project to figure it out. We found out that we had 9-1/2 volts indicated at one spot on the battery top. They washed the battery off and cleaned up around it and no more problems.

Had another student with 64 Chevy lowrider who was having dead battery problems when he got ready to go to school in the morning. He worked in a grocery store and left the car at home so it wouldn't get door dings in the parking lot. after about a week of jumping it every morning and going every thing electrical in the school shop his mom says "oh your little brother and his friends listen to your sterio every night when you are at work". He never said how long it took for his brother's bruises to fade away but he didn't have any more battery issues after a rather one sided discussion with him.

Still you should be able to hook up a multi meter in the negative cable and have it set on amps to see if you have a draw.

12-30-2020, 08:46 PM	#3
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,822	Re: Parasitic drain Do this before you go much further. Take your multi-meter and check across the top of the battery in several areas. Connect the positive wire to the positive post and take the tip of the negative wire and touch around on the top of the battery to see if you have power draining off across the top of the battery in any dirt or moisture that might be there. When I was teaching auto mechanics one of my student's truck would have the battery go dead in two and a half hours sitting in the parking lot. We would jump it, run it around to the shop and stick the charger on it and charge it and it would start right up and it charged right on the money. About three days of that and we made it a class project to figure it out. We found out that we had 9-1/2 volts indicated at one spot on the battery top. They washed the battery off and cleaned up around it and no more problems. Had another student with 64 Chevy lowrider who was having dead battery problems when he got ready to go to school in the morning. He worked in a grocery store and left the car at home so it wouldn't get door dings in the parking lot. after about a week of jumping it every morning and going every thing electrical in the school shop his mom says "oh your little brother and his friends listen to your sterio every night when you are at work". He never said how long it took for his brother's bruises to fade away but he didn't have any more battery issues after a rather one sided discussion with him. Still you should be able to hook up a multi meter in the negative cable and have it set on amps to see if you have a draw. Attached Images __________________ Founding member of the too many projects, too little time and money club. My ongoing truck projects: 48 Chev 3100 that will run a 292 Six. 71 GMC 2500 that is getting a Cad 500 transplant. 77 C 30 dualie, 454, 4 speed with a 10 foot flatbed and hoist. It does the heavy work and hauls the projects around.