Dumber than a fence post. First time diesel owner. Only thing I know is that the green fuel hose at the pump is the one I use.
2001 Cummins parked for two months. Went to start it and batteries almost dead. Charged them all night, started vehicle, drove to town, engine fully warmed. Stoped to have the batteries checked, (750 cranking amp), one was 620 the other 680 but the service person said the charging system was not working properly.(original batteries in truck) Checked it at another place with a diode type volt meter, same response. 1st thought=perhaps the voltage regulator was intermittent. Called the dodge dealer. Dealer said the voltage regulator was part of the alternator. Suggested that I buy another alternator. Called a second dodge dealer that said the voltage regulator was in the computer. Called a third dealer=same response as second dealer. Dashboard volt meter would go from 14+ volts down to 8 or so and back to 14 then to 11, it was all over the place. Recharged batteries for a second night. Started truck today and the in dash volt meter stayed on 14+ all the time it was running,(about 15 minutes). Truck has 36,000 miles on it. I have not the foggiest idea what is going on. Would you folks provide some insight for me please?

 

First off, congrats on finding a low mileage 01. When the grid heaters cycle, it'll cause the volt gauge to drop then return to around 14v, then repeat for around 30 sec, and the volt gauge should hold steady after wards.

 

Thank you wildbill,,,,,,,Next thing is "what the heck is a grid heater"?

 

if your looking at the truck from the front end, you'll see a gray metal tube coming up the right side to the engine and the grid heater is between that and the intake manifold...basically its there to heat the air coming into the engine when its cold outside, thats what is happening when the wait to start light is on when you turn the key before you start it.

 

Thank you . My voltage was fluxuating after the engine was fully warm. I will look for the heater as you have directed. Learning about diesel engines will be a whole new topic for me. I appreciate your feedback and help

 

 

Perfectly normal Arne. The grid heaters cycle (draws well over 100 amps), until the engine is warm or you hit 18 mph.

And FYI, the voltage regulator is controlled by the PCM. And you can wire in an external one if you have to - but I dont believe thats your problem.

BTW, welcome to the site

 

Thank you Dr. Evil. I did talk to a man about wireing in a regulator. He said that it was easy to do but I might get a check engine light and that might affect my next IM test for license. I will hold off for now and take the advice of you and others on this forum. Thanks again.

 

sounds like what happened to my truck when i rebilt my head, there was a little black box atached to the rear of the alternator that is held on my two locking nuts, they were loose on mine snugged them up and didnt have a problem after that

 

In a 2001 those stock batteries have long since worn out there life expectancy. Drop some cash and get ya a good set of new ones. Most any auto parts place should be able to test the alternator for you to make sure it's puttin out voltage and if it's not it's an easy change, not cheap just easy.

Another thing about testing the batteries on one of these dual battery systems, make sure they separate the batteries when they test them. If they are connected one of the batteries may be bad and the other still good. The good one will feed the bad one and make it appear good when it's not.

Welcome to the site. And also to the frustrated Diesel Jockey's Anonymous. You will find very few dealers out there that know squat about our trucks or even mechanic shops in general for that matter.