Is it normal during cold weather starts for the first 5-10 minutes for the voltmeter to show the system is not charging when the grisheater comes on while the engine is running?? When its cold the engine will start right up but the voltmeter will not come up at all for a couple minutes then it will bounce up and down when it is cycling?

 

Yes. The grids pull waaay more current than the alt can provide.

 

no wonder why im on my 2nd computer is it like that on all cummins generations?

 

Yes.

 

That is 100% normal for any Cummins engine with grids, not just Dodge apps, it's just how they are.

 

The heater assemble draws right at 220amps. The alternator's good for only 120amps. With the truck at a slow idle, you're gonna dip into the battery a little till things warm up.

 

Watch the headlights dim.

 

I didn't even know the grids cycled when the engine was running...I just thought they were for starting.

guess you learn something new everyday..

 

I've noticed this on my truck. The ones at work take awhile to warm up, some upwards of an hour. Unless its a cat or international the two batteries they use sometimes aren't even enough to start the motors. Ten minutes of cycle cranking on a ford 6 or 8 will kill most batteries. Cant use ether because too many people tried using it on power strokes and didn't know how :-)

 

The best way to warm up a diesel is to drive it (easy til the engine warms up). Mine can idle all day, and never get to the first thin line on the temp gauge. Drive it 3mi, and I have heat running me out. Ok, more like 8mi, but you get my point.

 

Yup, they come on and off. Watch the volt meter, you will see it dive then recover. Not sure on the first gens but my second gen has a trip point of 20mph. My first gen is a summer month only truck for me, never seen salt. She's parked now for the winter so not much experience with it in the cold.

 

I had the same question about the grid heaters, my 91.5 did not cycle the grid heaters on coldest days since I have had it. But my 93 seems to cycle them all the time starting from the low 60's.

 

Yep - bothered me for a little while until I understood it. The magic temperature is 59* F. If the air intake is below 59*F it will start the pre-heat cycle or post-heat cycle.

Alldata states that the heaters can cycle either together or alternate. All of this is based on the air temperature in the intake manifold.

Anyway - its a load of fun on a cold dark night and the heaters cycle and the lights go dim and old eyes do not see so well.

 

When my grids cycle with my engine running it is just barely noticeable.

David,
Just curious any idea how they come up with the figure 220-amps, are these each or a pair?

Looking at the wiring diagram the grids are connected to the 100-amp solenoids with about 6 feet of 6-gauge wire and then the solenoids are connected to the battery through a 14-gauge fuse link.

How do they draw 220-amperes through a 14-gauge wire without burning up the fuse link?

12.0 volts x 220 amps = 2640 watts? Ill bet the wiring puts out as much heat as the grids do.

Think it is time to pull out my ammeter.

The whine that you hear is the heavy current being drawn through the wire.

Jim

 

when i went to disconnect the grid heaters after all this was goin on the wires were real warm!!