Airdog lift pump running loud / lope

[jonathancasey19]

My Airdog 150 has approximately 85k and has run great until a few days ago. The pump is running very loud similar to a FASS. It can be heard easily inside the cab. Now the truck is loping at idle on all DSP tunes. FRP, FPRV and balance rates are normal. No spare filters on hand so I drained water separator and other filter. No leaks, not losing fuel, and fuel is returning back to tank. Only other time I've heard Airdog run loud is when its' sucking air (ran out of fuel). I've completely filled the tank and it lopes at 36 degrees outside and 70 degrees so I know it's not from cold temps and bigger injectors.


Anyone ever had an Airdog run very loud and loping?

Thanks

 

[Dirtymaxx03]

I know I had a bud who's PPE lift pump was going out and it got loud as fawk and made all sorts of noises till it let go. I'd get some new filters for it and throw em on

 

[jonathancasey19]

Yep. I fear the pump is going bad. If the lift pump supplies too much fuel pressure or an irregular amount, could it make the truck lope?

 

[MACKIN]

If the pump is pulsating to high psi sure it will.

 

[MACKIN]

I assume you don't have a guage? That would be the easiest way to tell.

 

[jonathancasey19]

No, sure don't have one. Could it damage the cp3 if I just drove it till it went out?

 

[MACKIN]

Not sure probably leak at the ficm or some where but how would I know as you don't even know how much pressure you pushing. Could screw up your frpcv . Best to fix it or shut it off IMO

 

[Dirtymaxx03]

I ran my fass at like 15 psi for a long time and it made my truck lope and didn't cause any harm. Now I have a gauge and it's set to 10psi

 

[Colt]

My Raptor pump is loud and runs at 15 psi without a lope. It's been on for a year and no issues of stops or sound changes while it runs. Sure makes truck run better and it stays on it's psi regulator setting real good. I use 2 stroke oil and power service in the fuel now for winter on the 70/30 winter mix from Cenex fuel supply. Injectors are nice and smooth and very quiet since it's an LBZ. Some of those guys say they have ticking noises in the injectors without any fuel adder to help lube them.I believe they're right because I started using 2 stroke oil 3 yrs. ago and it's been smooth and the pressures on the rails go to 28k when I get after it. Run that Delo 400 15w40 synthetic since new.

 

[jonathancasey19]

If pulsating PSI from lift pump causes a lope and can possibly damage the FPRV then how come a regular lope via EFI Live does not?

 

[MACKIN]

If pulsating PSI from lift pump causes a lope and can possibly damage the FPRV then how come a regular lope via EFI Live does not?

You should think about how you're getting a lope and you'll have your answer.

 

[1lowdiesel]

Here are 2 things you can check for.

First would be fuel pressure, that will tell you alot about what is going on.

Second would be to remove one of the small bolts from the back of the motor. Check to make sure it's dry and doesn't smell like fuel. Sometimes when the units get louder out of nowhere, it could also be from the motor getting wet cause of a failed seal.

 

[jdlover1]

mine lopes from the 26psi at idle. Pump will also surge if out of fuel,but you said tank is full. If a oring is cut they have a oring kit to rebuild them.

 

[jonathancasey19]

Well after a week or so of loping the truck decided to die while pulling out of the dealership from an alignment today. Fuel was pouring all over the pavement coming from the valley. Would not turn over, only "click". Had a rollback come pick it up. Only had time to glance down in the valley. Looks like fuel is leaking from the cp3, possibly a supply line. Maybe it was loose prior to shutting down which is why the truck was loping (air) and the airdog was running loud???? Anyway, keeping fingers crossed that this brand new lvl 3 pump is okay.

 

[PAT]

IMHO the ad isn't gonna run loud from a leak in the valley. From my experience, they get loud under higher loads (ie a kink/clog) and quiet under less of a load (ie a Leak down stream)

 

[PAT]

What do you mean by "click"? Kinda like a low battery and it doesn't spin the starter kinda click? Or is it turning and turning with no fire? Kinda like there is no fuel rail pressure?
Is the stealership fixing it all for you? Or will you still need our help to diagnose?

 

[jonathancasey19]

Definitely no stealership. Had it carried to Diesel Addiction. So far they removed the intake and can see fuel pissing out the bottom of the pump so that rules out the supply line theory. Cp3 is obviously shot. What's worse is the motor is locked up. Two guys couldn't get it to turn over from the harmonic balancer. I'm hoping it's because the pump is locked up and won't let gears rotate.
If they have time today they will pull the cp3 and see if they can turn the crank.

With that said, I called Airdog and they told me their pumps will run loud when they go bad. Obviously both Airdog and cp3 will need replacement.

Will have more later.

Thanks

 

[TeaBagger2006]

I seriously hope there is no major damage! I will pray for you man!

 

[jonathancasey19]

Thanks.

Anyone ever heard of a cp3 failing and motor not turning over?

 

[TeaBagger2006]

The only way I could see a failed cp3 keeping the engine from turning over is if the nut on the gear came off and jammed up the gears upfront.