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Putter
12-28-2007, 01:45 AM
I have a 95 CTD that starts poorly under 30*. It seems to me that the grid heater is not getting hot enough. If its warm and sits for 6 hours it will start fine, and if I plug it in for a few hours it starts fine, so I don't think its a fuel drain back issue. If it does start, lots of white smoke and misfires on a couple of cylinders, smoke quits once it starts hitting on all 6.

I know the grid heater is getting power because my headlights dim significantly, but I feel it is shorted.

What is a normal amp draw for the heater?

If I were to go out when its cold (20*) flip the key to run and let it run through one cycle, what should its external temperature be with a non contact thermometer?

whistlin'
12-31-2007, 10:07 PM
Could be only one of them is working. Check with a dvm or test light and see if they are both getting power when it cycles, could be a solenoid.

moparzrule
01-01-2008, 09:05 AM
I think something else is wrong. My 94' started fine without the grid heater under 30 degrees', ran a little rough for 30 seconds or so and I had to keep my foot on the pedal, but it still started right away with very little cranking. BTW my truck had 255K miles when I sold it.
You need to do a compression check, and possibly some injector flow testing. Your injectors might need replacing, when they get a lot of miles they can start burbling the fuel out instead of spraying a nice mist. The fuel needs to be a nice mist the detonate when the engine is cold.

moparzrule
01-01-2008, 09:08 AM
One other thing, 94-95's have 131 delivery valves which starve fuel delivery. Cummins upgraded the 96-98's with 181's. I installed 181's in my truck and it started easier then too. There's also after market 191's, they are under $200. I payed $100 for a set of used 181's.

Putter
01-01-2008, 03:48 PM
Could be only one of them is working. Check with a dvm or test light and see if they are both getting power when it cycles, could be a solenoid.

There is two of them? I only saw the on at the intake inlet.

Anyone have specifications?

turbovanmanČ
01-01-2008, 04:21 PM
Check your fuel lines. I had a customers truck do the same, we found a pinhole leak at the lines around the back of the bellhousing.

whistlin'
01-01-2008, 05:50 PM
There is two of them? I only saw the on at the intake inlet.

Anyone have specifications?

Yep, there's two of them:). Your symptoms sound typical of one not working from some owners. I've got to get the fuel lines for mine, sucking air after sitting overnight.:(

Putter
01-01-2008, 08:58 PM
Where is the second one at? I don't think its fuel lines, it starts instantly if its plugged in...

moparzrule
01-01-2008, 11:36 PM
Check your fuel lines. I had a customers truck do the same, we found a pinhole leak at the lines around the back of the bellhousing.

That must be a 1st gen. 2nd gen the lines don't go anywhere near the bellhousing, all 6 go in between the 3rd and 4rd valve cover or 2nd and third I don't remember, it's been awhile).

moparzrule
01-01-2008, 11:38 PM
Guess I should say it again. The problem isn't with the heater grids, most guys run without them. Something else is wrong. Just because it only does it when it's cold doesn't mean anything. The heater grids come on at anything below 60 degree's, but you say it starts fine unless it's under 30. Something else is wrong, I think you have clogged injector(s) and it's not spraying correctly causing a missfire when very cold.

turbovanmanČ
01-02-2008, 04:11 AM
That must be a 1st gen. 2nd gen the lines don't go anywhere near the bellhousing, all 6 go in between the 3rd and 4rd valve cover or 2nd and third I don't remember, it's been awhile).

Probably was but even still, all hoses have to cross over the bellhousing at some point, ;)

Putter
01-02-2008, 06:07 AM
I think I have it figured out, we'll see tomorrow, then I'll let everyone know how dumb I am...

Putter
01-02-2008, 06:10 AM
Oh and if anyone is wondering, a known good heater draws 205amps @ 10.5volts.

My heater draws 205 tapering to 165 @ 10.0volts, this should be enough to point out whats wrong with the truck... :)

moparzrule
01-02-2008, 08:19 AM
Batteries?

turbovanmanČ
01-02-2008, 05:15 PM
+2, battery's.

Putter
01-02-2008, 06:21 PM
+3 Batteries

Never dawned on me, they passed a load test when I did the used vehicle inspection on it at the dealership, but I never used a digital tester on them. They looked pretty recent so I just spaced it off.

One was frozen solid, the other was marginal, tested 400cca. Two new batteries and the damn thing fired right up at 8*f today without being plugged in.

moparzrule
01-02-2008, 06:24 PM
Good to hear it was something simple. Unfortunitely these trucks take 2 battery's, and they aren't exactly small ones OR cheap!