Possible Electrical Short, any suggestions?

[Adam]

I've been having trouble starting the van over the past few days. Not sure if this is related, but we had a couple of days recently where we forgot to switch back to diesel (from WVO) before we shut the van down for the night. This lead to some really hard starts in the next mornings. One was so bad that I ended up killing the batteries and needed a jump to get it started.

The non-starting symptoms are either clicking, or absolutely no sound and the radio and clock go dead until I turn the key back to the aux position. When I try to start and the hood is popped I get some nasty looking sparks from the positive terminal of one of my two batteries (always the same one). I was able to disconnect some of the wiring, reassemble it and get it started, but after I let it run for a bit and tried to restarted I got the same problem. I'm guessing there is an electrical short somewhere. I've disconnected all the PlantDrive electrics that I installed to take them out of the equation, but it doesn't seem to help. Any suggestions as to how I should trouble shot it?

[docsavage]

From the symptoms, it sounds like the dead batteries caused a few problems. Try tapping the starter with a hammer or other instrument when turning the key. The solenoid may be stuck - this can happen after a lot of cranking to start as the starter can get very hot. Also, check the grounds on the vehicle. A bad ground causes lots of other issues. Beyond that, someone else may have good ideas.

James

[mararmeisto]

I seem to remember someone saying something about jump starting these things being a bad idea... something to do with the glow plug circuit and it not liking to be a part of the jump starting process. Don't know if you'd have to disconnect the circuit or what, but...

I'll check the owner's manual I have at home when I get off work.

You probably didn't have a problem (other than congealed WVO in the lines) until you jump started the van... then you had a real problem.

Glen? Mardy?

[Adam]

Hmmm, ok, I've been able to start it several times today, but each time nasty looking sparks jump off the positive terminal of driver side battery. So I don't know if it is an issue with the battery or the ground, but I'm still fiddling with it. I think I'll give Glen a call.

[mararmeisto]

Hmmm, ok, I've been able to start it several times today, but each time nasty looking sparks jump off the positive terminal of driver side battery. So I don't know if it is an issue with the battery or the ground, but I'm still fiddling with it. I think I'll give Glen a call.

Are the battery terminals clean? Get yourself some baking soda, sprinkle it on top, rinse off with clean water and try again. Watch for sparks.

Also, is the battery connection tight? If not tight, it can spark, not charge properly and not supply voltage correctly when required.

[Adam]

I'll try cleaning the connections, they do look a little dirty. It looks like the driver side battery is the issue. I've totally disconnected it and it starts easily without any sparks, so I may needs a new battery or just need o clean the connections.

If I did get a new battery, should I replace them both, just get one new one, or substitute one really beefy battery for both of the original batteries?

[mararmeisto]

Batteries in parallel need to be changed together. It's expensive, yes, but otherwise you'll have a strong battery and a weaker battery and the strong one won't 'pull up' the weaker one - the weak one will 'drag down' the stronger one.

Try cleaning and tightening connections, and then failing that look at replacing the batteries. If you want to get an idea of what your battery's capabilities are (cranking amps and voltage), disconnect them from one another and have the mechanic put the battery tester to it (do this at the battery shop or mechanic's).

The diesel will start with a single battery, but two gives greater/longer umph for a compression start (should the glow plugs not be up to snuff). If you go with a single battery, you'll have to change the harness and look for a battery with a greater cranking capacity.