LB7: installing sending unit on 2003 GMC 2500HD

[not-a-canic]

I am new to the forum. Have search but did not find info I was looking for. Hope this is not a dumb question.
Am planning to replace my fuel sending unit in the fuel tank. Plan on doing it by lifting bed. Have looked at various youtube video but have not found one specific to the 2003 GMC 2500HD. At this point, I think I know what I am getting into, but have a couple of questions. None of the information I have seen talks about the fact that air will get in fuel line as a result of the process. I know the injection system is very sensitive to air so I was wondering if I have to purge air from system somehow after installing a new fuel sending unit? If so, how? Also was wondering if I need any special tools to disconnect fuel lines and electric lines. If so, where can i get the tools and what are the tool numbers. Thanks in advance for info.

 

[hondarider552]

Fuel lines are 1/2 and 3/8, Leslie makes a plastic tool kit for them on amazon, they are quick disconnects.

As far as the air, if you don't have a lift pump, you will need to use the factory primer on the oem fuel filter housing.

 

[briencolgan]

I just replaced my sending unit on a 03 Silverado duramax. I Have a service body on the back of my truck that's welded on. So I just drop the tank. Dealing with getting the filler neck on and off is hard but doable. But if you have a way to get the bed off it would be easier I think.

There's no issue with air in the lines. Just look for the little hand pump on the right rear engine. It's a metal button about the size of a shot glass on top of the fuel filter. after you get it all back together. Pump it up and it'll start.

You do need a 1/2" and 3/8 fuel disconnect tool. They are a pain in the ass to work with. I broke both of the fittings on the fuel sending unit the first time I did this on the rear tank. So be careful they are delicate. Those fuel disconnect tools are available anywhere, AutoZone or Napa. Sometimes you have to prime the truck quite a bit and turn it over a lot to get it started again. It's not uncommon to crank so much the battery goes dead. But it will eventually turn over and then run just fine after that.


Sent from my iPhone using Tapatalk

 

[not-a-canic]

Thanks for info

Thanks for info. That is exactly what I needed to know. Guess I will order the parts and have at it.

 

[six5creed]

I replaced mine by pulling bed and didn't bleed it all. No problems.


Sent from my iPhone 7 via Talkatap