ECM? After replacing alternator a month ago and VR, it fried battery

[GardnerM]

I picked up this 91.5 a month ago and resolved OD issue with TPS delete kit. Gave it a new alternator couple weeks ago. Yesterday it cooked my battery by overcharging. New battery,new VR ,cleaned connections grounded Vlt reg to block,sanded down alternator ground to block.
And its ,after running through heat grid cycles charges 15.2 volts and doesnt budge even after battery is charged up . Will I fry the new battery too? Fit to be tied after all the feeling good about the truck....

 

[jclark5810]

Mine was doing that, battery was boiling and spilling everywhere. The headlights were flickering etc. Pretty strange but I added another ground and it stopped. I'm nowhere near "knowledgeable" in electronics but it worked for me.

 

[GardnerM]

Mine was doing that, battery was boiling and spilling everywhere. The headlights were flickering etc. Pretty strange but I added another ground and it stopped. I'm nowhere near "knowledgeable" in electronics but it worked for me.

Where bouts did you add the ground

 

[ChrisWilliams]

Check your negative battery cable completely and make sure it doesn't have a bad spot somewhere. Could your new VR be bad?

 

[jclark5810]

Where bouts did you add the ground

I ran it right to the core support, about only a few inches. It seems as thought there was one that was supposed to be there originally. As mentioned too the negative battery should be inspected. I replaced mine with heavy gauge cable and marine style brass terminals.

 

[HHhuntitall]

Could be ground. Could be new Voltage Regulator. Could be the positive cable from alternator to battery. There is a connector next to the battery from the alternator that can corrode up from time to time, especially if a battery has spilled near it. The new voltage regulators are junk. I've seen new ones make one cycle of the grid heater and then peg the voltmeter.... I'd wager that's where your problem lies, but it could be something else. I'd try the cheapest first, then work your way up.

 

[Bob Beauchaine]

All the 1st gens I've seen had a ground built into the neg. battery cable that ran to the core support. I would just make sure that the connections are clean. I also installed a marine style multiple gang terminal for my existing and future wiring projects.

Bob

 

[GardnerM]

All the 1st gens I've seen had a ground built into the neg. battery cable that ran to the core support. I would just make sure that the connections are clean. I also installed a marine style multiple gang terminal for my existing and future wiring projects.

Bob

It was the 38 dollar VR from Napa. 15.2 volts .So I will try new batt conne tions first , nice and clean , then run a jumper from VR bolt to batt neg.

 

[GardnerM]

The needle on the dash operates as it should when cold it drops back to about 12 then back up to 15 and cycles like that till it gets warmer. Then it climbs to 15.2 and stays .

 

[DVolk]

They will cycle like that upon the initial start up for the day , I have gotten bad VR out of the box , it might not even hurt to add a ground from the engine to the cab . Most of the places that sell batterys tire shops or if you have an place that just sells batterys do free electricle checks id stop in there and see if it reads correctly . Ive also seen the fusible link take a dump sevral times ,

 

[JDancoe]

IMHO, you can't have too many, or be too well, grounded. Also, make sure the ground connections are squeaky-clean, and use some sort of anti-corrosive compound. I can't count the number of times I've found Dirt, Paint, and/or Corrosion under ground connections at the frame, block, and cab/body. Also, because the VR grounds to the cab, and the alternator grounds to the engine, be sure you have good grounds between the cab & frame, and the engine and frame.
Jack Dancoe