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AirDog 100 Woes.

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Bolt on "6 bolt" steering gear

2008 3500 - Weird clicking sound after switching heater setting

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On the AD\FASS the pressure regulator doesn't turn the pump on or off, it just bypasses fuel back to the tank when pressures exceeds its setting. That happens whether the engine is running or not, the AD\FASS delivery almost always exceeds demands so the regulator is always in play engine running or not.

The only real difference between engine running or not is the electrical system load. It may also depend on how the AD is wired; direct to key-on power and always on, or, run thru a relay that the ECM is activating. The latter adds wiring components and the ECM lift pump circuit to the equation, the former is just a battery draw with fewer components.
The current harness is wired to the alternator and ECM. It runs with the ignition on, but blows the fuse 15 seconds after I start the engine.

The only work I've had done in the past month or two is new serpentine belt, water pump, idler pully and tensioner.
I bought the parts from Geno's and a local shop installed them. They are the same shop that did my injectors last year and I have been pleased with their other work. A new issue has reared its head now since the new harness has been installed. The fuse for the HVAC has blown and blows every time I replace it.

Maybe someone can suggest a good/better mechanic in or close to
Corpus Christi, Texas?
 
Most mechanics aren't good at electrical gremlins. Go to an auto electric guy.
It’s comments like this that sour this forum. I don’t think the OP has tried any of these sensible checks.
It’s okay that maybe his capabilities are limited, but this board is known for going way beyond being helpful.
I know if this were my truck it’d be fixed already.
 
It’s comments like this that sour this forum. I don’t think the OP has tried any of these sensible checks.
It’s okay that maybe his capabilities are limited, but this board is known for going way beyond being helpful.
I know if this were my truck it’d be fixed already.
Not sure what you mean by "sensible checks". I found my FLUKE and checked voltage 12.68v off and 14.66 running.
We put a new connector between the CP3 and the line coming in and pressure is between 15-17psi right where its supposed to be. I have not checked amperage. The last time I tried to verify amps on something I had to find more fast blow fuses for my meter and I followed the instructions as best as I can recall. I can machine almost anything on mill, lathe, surface grinder, edm, and program cnc mills, but I'm not much of a mechanic or an electrician. Sorry if I have some how soiled the title of Cummins Diesel owner.
 
Don’t worry guys. Things can and easily do get taken out of context in written form all the time. I don’t think anyone meant any real harm. The guys are trying to help. That can be really difficult to do in written form on the internet. Take it all with a grain of salt my friends. ;)
 
Not sure what you mean by "sensible checks". I found my FLUKE and checked voltage 12.68v off and 14.66 running.
We put a new connector between the CP3 and the line coming in and pressure is between 15-17psi right where its supposed to be. I have not checked amperage. The last time I tried to verify amps on something I had to find more fast blow fuses for my meter and I followed the instructions as best as I can recall. I can machine almost anything on mill, lathe, surface grinder, edm, and program cnc mills, but I'm not much of a mechanic or an electrician. Sorry if I have some how soiled the title of Cummins Diesel owner.
That's because most multimeters I ever saw or used in 50+ years only goes to 10 amp max. You would need an inductive meter, my Fluke 374 goes to 600 if I remember right and it is a multimeter inductive amps.
 
We put a new connector between the CP3 and the line coming in and pressure is between 15-17psi right where its supposed to be.
To me, that sounds a bit high. My new on canister lift pump is 7-10 psi steadily. I know lift pumps don’t need to push much- it’s volume we’re looking for. I’m suspicious of that regulator.
Is there a spec by air dog on the pressure to CP3?
 
From what I read anything below 7 amps is normal. If your blowing a 20 amp fuse there is definately not normal. I do not know why they are giving you grief on this. They should replace the pump or the motor.
 
I know Air Dog at least used to recommend hooking to the alternator but I've never liked the idea of that direct connection. I tied mine into the driver's side battery.
 
I know Air Dog at least used to recommend hooking to the alternator but I've never liked the idea of that direct connection. I tied mine into the driver's side battery.
Mine was tied to the battery when all this started. I also had the older harness that does not plug into the ECM for a signal to turn on the pump. 15-17psi is what I understand the FP-100 was set to put out. I went with the alternator hookup this time due to the grid heater and a some other stuff being connected to the drivers side battery. That battery was really sucked down when I replaced it. 158CCA the passenger side battery 330.
Gerotor and filters were the 1st things I checked...
I learning as I go.
 
Unless AD finally gives in your gonna have to hit them with facts involving pressure, voltage and amperage. You probably would need to have this all set up, start the truck and observe all three until the fuse blows. There is a method to this madness.
 
It’s comments like this that sour this forum. I don’t think the OP has tried any of these sensible checks.
It’s okay that maybe his capabilities are limited, but this board is known for going way beyond being helpful.
I know if this were my truck it’d be fixed already.

I may be wrong, but p-Bar was referring to the "local diesel mechanic" Drewhenry mentioned in his very first post, or he was reacting to Drewhenry’s last statement in post #41, “Maybe someone can suggest a good/better mechanic in or close to Corpus Christi, Texas?

He was NOT referring to Drewhenry himself.
 
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Mine was tied to the battery when all this started. I also had the older harness that does not plug into the ECM for a signal to turn on the pump. 15-17psi is what I understand the FP-100 was set to put out. I went with the alternator hookup this time due to the grid heater and a some other stuff being connected to the drivers side battery. That battery was really sucked down when I replaced it. 158CCA the passenger side battery 330.
Gerotor and filters were the 1st things I checked...
I learning as I go.

Then your cross over cable is bad.
The two battery's work as one big unit, such a difference indicate a deeper problem in your system.
Could be grounds as well.

PS, never replace a single battery in a dual setup, you ask for problems that way.
 
How much resistance should this cable show if it is still good?

A resistance test on high current handling wiring has no value other that it will show that there is continuity or there is no continuity.

Example of a scenario: Your crossover cable has one good single strand of wire making a good connection. Continuity test will pass with flying colors. Try running 200 amps through that single strand of wire and see how that works out for you.

Now performing a voltage drop test from the passenger side battery (probe on the positive post) to the driver side battery (probe on the positive post) while the engine is being cranked for about 10 seconds will provide you with great diagnostic information. If the test results show less than .1 (one tenth) voltage drop under these conditions, then the crossover wire and connections are good. If the voltage drop is significantly greater that .1 volt, then you need to perform more voltage drop tests to isolate the exact location of high resistance.


- John
 
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