In the early 6.0L days the sump idea had a lot of attention and discussion ..... opinions were varied and there was a lot of emotion back then too.

There just haven't been any documented cases on the forums about damage to the sump or fuel lines. No doubt it could happen, but it would have to be in a rock-climbing environment (or something similar). Hitting an animal on the road or driving through rough terrain on the ranch just isn't going to cause any damage to the sump or fuel lines. It is well protected by the "upstream" components. IMO time has shown that there is no need to worry about damage to it.

As far as pump suction pressure, fluid flow, dissolve air release, etc ............... If the suction line (tubing) pressure loss from flow is minimal (it may or may not be, who knows) then the pressure at the pump suction will be essentially the same with a sump or a pick-up tube. It is independent of the path and determined only by the starting elevation (level of fuel in the tank) and ending elevation (location of the pump). Yes a pick-up tube will have a lower pressure at the highest point of the tube as the fuel is lifted, but the pressure will be regained due to the higher elevation between that point and the pump.

The 6.0L plastic foot has seen some failures no doubt. That said, the percentage of failures is low. The OEM pump has been shown to have a reasonable reliability. Some early failures have occurred, but I bet many of those were connected to bad fuel experiences (algae or fuel gelling restricting the suction line etc). Bad fuel can cause issues regardless of what pump suction configuration you have! That said, reasonable reliability is sometimes not good enough for the "enthusiast"! The fuel system can certainly be improved, and many people have implemented some very innovative ideas over the years!

The fuel delivery of the stock pick-up system and the stock fuel pump has proven to be adequate for supporting the stock injectors - even when tuned. The system does not NEED a sump modification. That said, I have almost pulled the trigger a few times myself.

IMO the sump advantages are:
1. Even though failures have been relatively low on the pick-up tube system, there have been some (it is not a rare instance by any means). The sump eliminates that possibility.
2. If you are going with "larger than stock" injectors , then having the sump enables the owner to increase suction line size more easily AND enables a shorter run of suction line (tubing).
3. If you get a bad tank of fuel, it is easier to drain the tank.

Thanks for starting the thread, it has some good discussion. I didn't know about Bean's micro-sump. That is interesting to know!

 

Yes Mark you make very intelligent points and I always appreciate that. I am just not too excited about cutting a hole in the skid plate (Excursion) and tank. The way it is set up now it works but just have to be sure to fill up at 1/4 tank to be safe. I like the idea of installing that Beans Micro Sump with a metal access cover on the skid plate but I think I can get the stock foot to fit and work. I probably should have just ordered that whole 6.7L sending unit yesterday and modified it. I looked and thought I had the quick release fittings for it but don’t. The 12mm return fitting is $12 and feed is 1/2” and $22. I used them on the pump connections. I would rather just see if the foot fits and if not I could just do the sump and extend the 1/2” tube down into it like possessedmufflershop said he did.

 

You got me to thinking when you said "If I was buying a truck and found out it had a sump I would probably pass". I have to admit that if I were buying a used 6.0L and saw a truck with all the modifications I have installed ........... I would have to pass also - lol!

 

Sight unseen what kind of mechanic the owner was, same here man.

 

Considering all the branches I've pulled out from the undercarriage of my trucks at the farm, while I've thought of the sump, I can't go there. I'd always worry about a leak too.

The other thing going for the stock foot too is it is in someways a bell pickup.

 

The good thing about the Excursion is the tank is behind the rear axle and has the thick steel skid plate with enough space to route the feed hose through for protection. If I go with a sump I’m going to cut a round access hole in the skidplate and have my buddy fab an access plate for the sump that will cover the housing. I may or may not have ordered the Beans Micro sump this morning...I know I’m all over the place but it is really the best option at this point. I will keep the return through the sending unit and just cap the feed and use the $18 10AN barbed fitting on the sump. I think I will have enough existing hose. The 6.7 sending unit was $80 plus another $35 for the quick connect fittings and I was still uneasy about the stock pickup foot mating with the 1/2” stainless pickup tube.

 

This thread has covered a lot of territory in one day. A few points:

1.) After seeing Pete's pics I need to make a correction to my earlier post. If the OD of the top of the foot is exactly 1/2" then there is no way the OD of the pick-up tube is 7/16 as I assumed. I'm kinda surprised nobody has called me out on that. Having just been in there a few months ago I should have remembered it to have a 3/8 OD just like the supply line on the HFCM.

2.) Smack, if the main concern is waiting longer than the 1/4 tank point to refill, then why not just extend the pick-up tube with a coupler? Here's what I did after discovering my foot had disintegrated:


Of course I would use stainless fittings next time around. With this setup I was able to go 60 miles once the low fuel light came on. The screen kept it about a 1/4" inch off the bottom of the tank at a minimum. Never had an issue with it clogging despite all the bacteria clumps in my stored fuel.

3.) My truck being an FX4 has the steel skid plate under the fuel tank also. I would have no qualms about cutting a hole to clear a sump, and bolting a fabbed cover plate to the skid plate for protection of the sump and fuel line. The more I think about it, the more I like the idea. And since I wouldn't have to modify the sending unit (I could just remove the foot and cap the top of the pick-up tube) it wouldn't void the lifetime warranty. And $60 for the Beans kit is a very attractive price.

 

Fuzz, when I modified the sending unit I made the pickup tube about 1/4” from the bottom of the tank. I can’t go any lower. After I ran the first tank of fuel down until the Low Fuel light came on I parked at my girlfriend’s flat driveway and when I pulled up the fuel pressure started to drop (with the 6.7 pump it was rock solid 68psi) so I shut her off and when J cranked back up the fuel pressure was jumping around and the engine started to stutter at idle so I shut it off, went to the gas station with her car and came back with 18 gallons of diesel and my fuel pump battery with leads to hot wire and purge the fuel system and it never did it again. Since that day I never let it get below 1/4 tank and it never did it again. I wasn’t about to ruin my injectors.

 

Also Fuzz, I think your tank on the trucks has an indention where the feed tube can be lower than the rest of the tank basically a sump. My Excursion tank doesn’t have that, it’s flat.

 

That's crazy.

Yes, you can see that recessed "sump" area at the lower right, but that's not going to account for roughly 5 gallons of fuel, which is what I'd need to go 60 miles after the low fuel light goes on. Maybe there's something wrong with your fuel level sensor?

 

Maybe I can’t measure and it’s an inch shorter than I thought? Haha I’ve been known to go looking for that material stretcher a time or two in the past. I never tested it again but didn’t want to compromise my injectors.
My foot looked better than that one when I pulled it out, it was still stuck on the tube but the foot was cracked and screen was sloshing around in the tank.

 

"The inch thing" as we call it around here is a real phenomenon. And it's almost always an inch shorter! God forbid it to be an inch longer so you can re-cut it.

Might be worth another measure.

 

I’d classify it as a small indentation slightly larger then the foot.

I’ll just bring up the point I was trying make earlier. The overall design of the system with the unbaffled tank was to allow any sucked up air to rise to the top of the secondary filter, be blocked by a whetted filter and eject by the return side of the secondary filter channels to the tank where it can be vented.

 

I caught that in your earlier post, thought about it and decided to go with the Beans Micro sump and just pull fuel off the bottom of the tank and be done. I’ll plug the feed fitting and just move the line to the sump. Lots of folks are running a regulated return and sump with the secondary fuel bowl deleted and have hundreds of thousands of miles on their injectors. The secondary bowl was restricting my fuel so I cut it off when I did my 6.7 pump and CAT 2 micron secondary filter. I hope I have no issues, now you have me second guessing my fuel system! Haha