Thursday, March 10, 2011

Battery Isolator Terminals

Here is another maintenance item for you.

Last week I was poking around under the hood when I noticed a lot of corrosion on the battery isolator terminals. Grabbing onto the wires, I could move them around. The nuts appeared to be tight and the studs themselves were moving. Using a multimeter I checked and found a small amount of voltage drop over two of the terminals, indicating a poor connection. I removed the screws holding the radiator reservoir in place and tied it back to provide access to the isolator's terminals. After disconnecting all power, the starting battery, coach battery, converter and solar panel, I removed the three nuts on the isolator and pulled the wires terminals off. At the base of each isolator stud, there is a thin nut. I snugged each of them up without over tightening since I did not want to break off anything inside the isolator.

The wire terminals were cleaned with a stainless steel brush and then everything received a coating of dielectric grease before reassembly. Checking afterwards, I found no voltage drop.

Contributor: Larry Wade