Replaced in dash switch. No luck. Still loses pressure off front tank. Any ideas?

 

Mine wasn't the switch, it was the harness that plugs into the switch

 

here is what hes talking about, thanks goes to subford.


again heres some wiring to help, again thanks to subford.

 

hmm, guess i was looking up that info for a few minutes. ok so not the switch., id just start checking for open lines or resistance between the lines.

 

Hey guys, Excuse me for asking on Christmas Eve but i removed the return on the front tank and cranked truck while switched on rear tank. Im getting fuel through the return line on the front tank. Is this normal?

 

Yes. There is a check valve in the fuel pump that shuts the flow off if the pump isn't pumping. When you are on the back tank, the check valve in the front stops the flow to that tank. On the front tank, the check valve in the rear stops the flow to the rear.

One of the problems with this system, if the check valve fails, you can overflow a tank from returning fuel to the wrong tank. There was a recall on this, they added an external check valve, but that recall has expired

 

Ok here is where I am at. I replaced the external check valve on the front tank. I am still getting fuel in the front tank when switched to rear tank. My question..... I installed a Napa N67000 pump in my front tank. Does this pump have a check valve on the return line? I am thinking that is why im losing fuel pressure off my front tank. Am I maybe on the right track here?

 

Disregard last post. Checked the Bosch website. It's the correct pump.

 

Ok Im replacing fuel lines from the front pump. My question is I need to replace the block on the frame rail where the fuel line goes fron 2 lines back to the filter. Whats the easiest way to go about this. Do they make a replacement "T" connector? I noticed a small crack in the block on the supply line from the front tank. Thanks for all the help!