I have seen many posts about in tank mods and fuel line from sender tube to fuel pump. Sounds like to me the main air problem is air sucked in through the two oring fittings on the fuel hose from the sender assembly to the pump? I have plenty of quality 3/8 fuel line lying around. Has anyone just replaced the line from top of sender to fuel pump with worth wile results? I cannot afford the $ or time to do the in tank mods at this time. Is it possible to get the factory line off and push a new hose over the fitting and get clamps on without removing the tank? And witch line is it? The bigger of the two I assume? Any tips would be great. Thanks as always!!

 

You'll have to drop the tank or lift your bed to get access to the top of the sender, but once you do that, swapping out the line should be a piece of cake and very beneficial.

 

A buddy of mine did this, and liked the result, but he may not know what he's missing by not doing the rest of the in-tank mods. I'd say 'go for it' - and be sure your fuel line is 30R9 rated, not 30R7, which is the cheap stuff not rated for diesel. You can always do this now and do the in-tank mods when you are better suited to do them. Anything would help over the stock setup.

 

Generally speaking, I prefer a rigid fuel line vs a rubber line when possible. Are you having a problem with air in your fuel? If so, then you are going to have to drop the tank anyway because the source of the problem is in the tank. I don't think the factory pre-pump fitting allows air into the system unless there is a restriction in the tank.

I haven't (yet) done the in-tank mods either but I've pondered it quite a few times. I didn't think my in-tank screens were clogged but how can you ever be sure unless you drop the tank and check? So, I figure it's better safe than sorry and decided I was going to do the work....then I changed my mind (again) and used my money to buy a fuel pressure gauge instead. I figure a restriction in fuel flow will show up on the gauge so I'll drop my tank if/when that time comes.

Last fall, we added another 7.3 Power Stroke to the family stable and it had about 180k on the odometer at that time. It also had been sitting in the dealer's back lot for about 4 months before I purchased it. After about a week of driving, I noticed the fuel pump had become much louder than my truck and I wondered if it was going out, so I connected a temporary fuel pressure gauge and noticed the pressure was about 38-40 psi (IIRC). I drove it to our neighborhood station, poured about 60-80 oz of Diesel Kleen in the tank and filled it up with new diesel. I drove back home and let it idle in the driveway while I literally watched the pressure climb back up to the 55 psi range where it's been ever since. Must have taken about 15 minutes or so...
Oh yeah...the fuel pump noise went away and it sounds normal again.

At this point I can only conclude that Diesel Kleen helped clean whatever may have been blocking the screens in the tank but I'll never know for sure. Even so, I decided to purchase two kits from DI just in case I ever need them but so far they are just collecting dust on my parts shelf.

 

Greg - do the Hutch mod - you'll wish you'd done it sooner. I attached a clear line to the fuel bowl drain and before the mod, it was full of bubbles. (I opened the fuel drain and turned on the ignition and watched the fuel go by). After the mod, it was totally clear.

But, the biggest satisfaction was the cackle going away, being replaced by a warmer, friendlier diesel clatter. Instantly noticeable. I installed a fuel pressure gauge under the hood and it reads 60 psi cold and 50-something hot. From doing all this, I mostly got a much better feel for the inlet side of the fuel system.

 

I tried that as well but in my test there were no bubbles. I also did something similar post FPR to see if there were bubbles in that line....none found. I'm not aware of a cackle issue with either of my trucks. Most 7.3 owners that I know have commented that my trucks sound fairly quiet by comparison, even those that have performed the in-tank mods.

It's one of those things that I am monitoring though. I have the kits so one of these days I'll be bored and go ahead and do the mod...or I'll be forced into action when my trucks begin acting up. It is on my PSD list though...but that list is much longer than my wife would like.

 

Replacing external lines does not correct problems in the tank. Many of us found the foot separated from the mixer in the tank - the parts and materials of which were a poor design and quality/too cheap.

 

The 30R7 is rated for Diesel, it is just rated for working pressures of 50 PSI or less. The 30R9 has a higher working pressure (100 PSI) and is also rated for Biodiesel, which can have ill effects on regular diesel rated hoses.

The 30R7 can be used for the line from the tank to the pump as it is suction only. If you ever plan on using straight Biodiesel, plan on running the 30R9......or better yet 30R10 (hose made to be installed in the tank).