So on my way to work this morning I noticed my pedal was for the most part dead. No acceleration and the engine was "missing" for lack of a better term.

 Made it to work, truck idled smooth like any other day but if revved a few times it would begin to miss again.

 Had the OBD scanner in the truck so plugged in and saw the P0216 code. That was the only code present.

 I know this is the VP death code but before I drop big $$$ on a pump, is there anything else I need to look at? I want to properly diagnose this and not just throw money at it. Can't afford that rout right now.

 Thanks in advance......

  On 1/17/2022 at 8:29 PM, JAG1 said:

Interesting conversation. The law regarding the sump is written because if in a wreck with a fire they don't want fuel to be pouring out. I think I found it once in the D.O.T. regulations. If the insurance got a hold of the info, modification to the fuel supply, which caused issues, it might place you in a very awkward position even if the accident weren't your fault. I say this to protect you guys.

Racor has them specifically for the suction side of the system.

I sell loads of the cat ones, Part number 525-6206 just posted 2 to a Guy in Scotland this very morning, got 17 on the shelf

  On 1/17/2022 at 8:35 PM, wil440 said:

I sell loads of the cat ones, Part number 525-6206 just posted 2 to a Guy in Scotland this very morning, got 17 on the shelf

 What size are the inlet/outlet on those? I'm wanting to run 1/2" line so will that even work? 

 I have a filter head from a log splitter that I scraped. Could I get a spin on filter for that? Something that isn't super fine but to catch anything that might kill the pump? I could put 1/2" barb fittings on that to easily install the new fuel line onto.

I can measure in the morning but from memory they are unequal one side is bigger

Spin on filters are typically finer and usually paper

  On 1/17/2022 at 7:07 PM, Tractorman said:

 

I am unable to follow the logic here.  Can you offer an explanation?

 

- John

 

As for the cavitation problem was brought forward back with the Carter lift pumps since they return from the output to the input. When you fire up the pump and zero flow but max pressure the non-returning pumps would create air bubbles in the solution. So the video I watched was with a Carter lift pump. and when the pump fired up and flowed max volume and then shut off the flow the suction side line would fill with air from the fuel returned back to the input side. 

 

This was one of the things that AirDog was in design because the AirDog and FASS would return to the tank. If the pump was dead headed and no flow of fuel it would not create cavitation. Simply because the pump would be flowing 100% on the return line. 

  On 1/17/2022 at 8:05 PM, wil440 said:

Cat use large mesh pre filters 

You said the magic words there "large mesh"  this is more of a strainer than a filter and there is a difference.   It's purpose is to catch any large particulates.  The pump should be designed to handle any normal sized particles and push them on through to the main fuel filtration.  This main filter is where the particulate separation occurs.  The fuel is being pushed through this filter instead of being sucked through.  Makes a big difference. 

  On 1/17/2022 at 8:29 PM, JAG1 said:

 I think I found it once in the D.O.T. regulations. If the insurance got a hold of the info, modification to the fuel supply, which caused issues, it might place you in a very awkward position even if the accident weren't your fault. I say this to protect you guys.

I appreciate the heads up.  I'm not doubting you, I just can't find the actual law that says sumps are illegal.  You read so many different things on different forums, I just like to confirm.  The only law that I have seen so far is that it must be protected from damage.  This was my original concern when I installed the sump.   After all it is on the bottom of the tank.  I'm considering building a skid plate for it.....considering....it's been on there for 5 years and I still haven't done it lol.

  On 1/17/2022 at 9:58 PM, ddmk6 said:

You said the magic words there "large mesh"  this is more of a strainer than a filter and there is a difference.   It's purpose is to catch any large particulates.  The pump should be designed to handle any normal sized particles and push them on through to the main fuel filtration.  This main filter is where the particulate separation occurs.  The fuel is being pushed through this filter instead of being sucked through.  Makes a big difference. 

Agree 100% 

  On 1/17/2022 at 8:52 PM, Doubletrouble said:

Could I get a spin on filter for that? Something that isn't super fine but to catch anything that might kill the pump

Yes, you can. See my signature for the Donaldson part number I run. It's a 140 micron screen. You'd have to find whatever model number has the dimensions that match your filter head. I used a cheap WIX filter head, then drilled and tapped the frame 5/16 fine.

 

Here is where I posted pictures and all the part numbers.

 

 

 

  On 1/17/2022 at 11:53 PM, LorenS said:

Yes, you can. See my signature for the Donaldson part number I run. It's a 140 micron screen. You'd have to find whatever model number has the dimensions that match your filter head. I used a cheap WIX filter head, then drilled and tapped the frame 5/16 fine.

 

Here is where I posted pictures and all the part numbers.

 

 

 

140 microns isn't really large mesh, the Cat prefilter or screen is designed to take out lumps as @ddmk6 says and would add zero restriction as it's more like a very coarse pan scourer or rocker cover breather oil separator

@LorenS, that's exactly what I was thinking. I had talked to you before about it. I just couldn't remember who it was I had talked to. Lol 

 I like that's it's short and doesn't hang down below the frame. Also where you mounted the pump looks pretty well protected.

FASS shipped the DRP with a 100 micron inline screen, but it is small so average velocity through the screen would be relatively high. The factory installed a screen in the tank, which I removed. I upsized the fuel lines to 3/8 from 5/16. I am not worried about the minute pressure drop through my screen, and am glad it's there to protect my $300 lift pump and prevent a tow bill because if trash wipes out one, I'm not installing the spare to have it destroyed, too!

100um water separator / pre-filter AirDog 150.

 

 

 

Take it a step further now. I'm also running 3um on the AirDog 150 and then 7um NAPA filter in the stock can.What I started doing years ago was cutting the cans off the AirDog filter and looking at color of the media. I found that with my drawsstraw in the main fuel body not in the sender basket I get cooler fuel. Now my filters last much much longer I change both stock and AirDog filters every 60k miles. That is 4 times longer than stock. The stock setup with drawing fuel from the sender basket is much much hotter fuel which now produces Asphaltenes this is where the fuel temp exceeds 150*F and now the black asphaltenes start showing up in the fuel filters. 

 

15,000 miles on a Fleetguard Filter 3um.

 

My filters stay much much cleaner longer and way less issue with injection pumps and injectors. My fuel temp typically below 130*F even in the summer. 

In this application (in my opinion) I think the 140 micron screen would be fine maybe even 100 microns.   A 5 micron FILTER would not.

I'm not sure what size it is but the Raptor pump has an inline screen inside the inlet fitting on the pump.  I don't remember the mesh size off the top of my head, next time I clean it I'll take a look.  I seem to remember it being pretty coarse, maybe even 200 mesh (don't quote me on that).  The key here is that it is a screen and not a restricting filter.  The only goal is to stop particles that will damage the pump.

I did not want the inlet screen. I took those out and provided a Racor, factory designed for the suction side, 30 micron 60/90 GPH prefilter. Been really good to me so far. Engines at sea use them and a running engine is a live saver in hazardous conditions.

 

You do not want to rely on a teeny little inlet screen take that out and put a good prefilter on.

 

A water separating prefilter's job is to stop the lift pump from elmulsifying the water into tiny droplets making it harder for the factory filter to do it's job of removing water.

I never liked the little screen inserts. Doesn't take much before it plugs up from debris or gelled fuel and then you stuck. Rather have the spin on filter personally. Again Raptor pumps have no return port to the fuel tank so cavitation is a real problem with these pumps. Then the adjustable regulators are problem prone too. Not like the old school spring and check ball like the full AirDog or FASS pumps have.

  On 1/18/2022 at 4:43 PM, JAG1 said:

Engines at sea use them and a running engine is a live saver in hazardous conditions.

Next time I take my truck out to sea I'll put one on.    

Smart ash! I can see you never want to try winning a debate around here... too many cowboys! No better place to be really.

  On 1/18/2022 at 6:26 PM, Mopar1973Man said:

I never liked the little screen inserts. Doesn't take much before it plugs up from debris or gelled fuel and then you stuck. Rather have the spin on filter personally. Again Raptor pumps have no return port to the fuel tank so cavitation is a real problem with these pumps. Then the adjustable regulators are problem prone too. Not like the old school spring and check ball like the full AirDog or FASS pumps have.

 The Fass ddrp pumps don't have a return line either. Are those also prone to cavitation? 

 I'm trying to do this on a budget as it's been a little slow at work and so on. But I want to get the best I can for my money. I can't do a full airdog setup though. 

 My thoughts are a replacement pump (fass ddrp, Raptor, or the like) with a pre pump filter (screen/mesh type but spin on) and 1/2" fuel line with draw straw. 

Maybe @W-T would be kind enough to explain why a return line lift pump (dumping excess pressure into the return) has less chance for cavitation than one that does not. Also does the return type L/P help to continually polish the fuel by circulating more volume thru the prefilter?

 

 

  On 1/19/2022 at 7:26 PM, JAG1 said:

Maybe @W-T would be kind enough to explain why a return line lift pump (dumping excess pressure into the return) has less chance for cavitation than one that does not. Also does the return type L/P help to continually polish the fuel by circulating more volume thru the prefilter?

 

 

 I would think yes, the return type would help to continually clean or polish the fuel.

 As far as the cavitation,  I think that would be from (forgive my layman's terms) the fuel not being able to continually move forward. A 150gph pump moves alot of fuel, that's 10 quarts or 2.5 gallons a minute. There is no way or engines use all this as we already know. The remainder is cycled through as a cooling liquid for the VP. Here's the issue. We run 1/2" line to carry this fuel, the return line is what? 5/16 coming out if the VP? There is a restriction. Which doesn't allow the fuel (150gph) to move fast enough which would create a bit of a jam at the pump impeller which in turn could be the creator of the cavitation. Based on the idea that an impeller in fluid that isn't moving at the same or similar speed as the impeller would cause turbulence and induce a cavitation effect.

 

 This is just my theory,  I hope I explained it in a way that it makes sense. I have the idea in my head but can't always put them on paper. Or there is the possibility that I'm just full of crap and completely wrong.

 

  On 1/19/2022 at 8:52 PM, Doubletrouble said:

This is just my theory,  I hope I explained it in a way that it makes sense. I have the idea in my head but can't always put them on paper. Or there is the possibility that I'm just full of crap and completely wrong.

I quoted what you said as it may also be relevant to me

Cavitation is a phenomenon in which the static pressure of a liquid reduces to below the liquid's vapour pressure, leading to the formation of small vapor-filled cavities in the liquid. When subjected to higher pressure, these cavities, called "bubbles" or "voids", collapse and can generate shock waves