2011 Peterbilt 389 fuel won’t stay equal

[5022]

I think when I had my 2013, pete's fix was fittings back into the tanks on the return lines with the orfices reduced. After replacing them I don't remember it being a problem. Dealer had the updated fittings in stock. Hope this helps.

[Rawze]

(09-30-2020 )Ben50291 Wrote:  ... I do have ports on the bottom of tanks. They are a 3/8 inch plug. Is there fuel line available in that size? Is there a special "goop" to put around elbow fitting so that fuel wouldn't leak out around it.

putting a crossover tube at the bottom of the tanks is against D.O.T. regs from what i remember.

[Lonestar10]

its against DOT regs unless your truck is diesel. to many trucks hit stuff on the roads and dumped their fuel everywhere so i high recommend not even giving the thought another eyeota of time.


went read it i guess diesel tanks are exempt....ok but here it is.

Drains and bottom fittings.

(i) Drains or other bottom fittings must not extend more than three-fourths of an inch below the lowest part of the fuel tank or sump.

(ii) Drains or other bottom fittings must be protected against damage from impact.

(iii) If a fuel tank has drains the drain fittings must permit substantially complete drainage of the tank.

(iv) Drains or other bottom fittings must be installed in a flange or spud designed to accommodate it.

so if you can keep your fittings under 3/4 inch when measure from tank bottom to bottom of fitting then i guess it can be done.

[Ben50291]

Wow. Thank you all for your responses. So as I sit here and scratch my head I'm wondering... the return line splitter was visually an open "t" as is the intake. I replaced them both but I was able to get one for the return that has plates and springs to help equalize pressure. Now that I have a valve on top of the tank I could put the original t back on and restrict flow back but I don't see how that could help the tank draw. Am I missing something? Thanks guys

[Volvo8873]

(09-30-2020 )5022 Wrote:  I think when I had my 2013, pete's fix was fittings back into the tanks on the return lines with the orfices reduced. After replacing them I don't remember it being a problem. Dealer had the updated fittings in stock. Hope this helps.

I had this tank equalization problem too with my Volvo when I switched tanks. Turned out I needed the reduced fittings on the return lines which the new ones did not have on the tanks... Swapped them out and no issue since.... still actually has me wondering how that is myself.

[Ben50291]

Ok guys. Here's the update. I crawled under the truck again I unhooked the fuel lines. The splitter valves are brand new draw and return. The fuel lines are brand new with no obstruction and no kinks or breaks. The draw tubes are steel inside the tank and are not blocked or cracked. I also have restriction valves that I can adjust installed on top of tanks for the return lines. It had not been drawing at all on passenger side tank which is a120vs driver side is an 80. I am going for a 1 day run tomorrow and I'll let you know if the truck starts to draw on passenger side now. Thanks for all your suggestions, i appreciate it

[Ben50291]

With valves on the return and draw both tanks, it works great

[Chamberpains]

Just reading over Lonestar10 post. What a lot of people do to keep the fitting from being lower than the bottom of the tank is to loosen the tank straps and rotate the tank enough to keep that from happening. You lose a little accuracy on the fuel level sending unit. But the pickup and return lines usually have hose attached on the bottom of them that are weighted so they roll with the motion of the truck. There would be no loss in usable fuel in the tanks.