Fuel line Issue

[GorillaGlue]

In my 89 k5 blazer, I installed a new sending unit, and the braided stainless lines were completely rotted at the fittings. Assuming that I secured everything the correct way and double flared my hard lines, could I just run rubber lines to the sending unit? The pressure should never exceed 15 psi and from what I’m aware, a good 350 tho stays around 13 psi. Would this be dangerous or at risk of leaking?

 

[Chickntrk]

The pump is capable of way more than 15 psi, the regulator is what keeps it there. Personally I’d rather see you use AN fittings, but you could use a short section of rubber hose secured with fuel injection clamps (not worm gear) . Just remember to check the rubber frequently as todays ethanol gas isn’t friendly to rubber hose.

 

[Bent77]

There is rubber hose specific to fuel injection. As mentioned, using it in sparing quantity is better

 

[mrk5]

The TBI pickups use rubber lines to the sending unit. I always thought it was interesting the Blazers and Burbs have the stainless braided and the pickups didn't. Maybe because the K5/Burb lay on the tank for a longer distance.

 

[GorillaGlue]

The TBI pickups use rubber lines to the sending unit. I always thought it was interesting the Blazers and Burbs have the stainless braided and the pickups didn't. Maybe because the K5/Burb lay on the tank for a longer distance.

Appreciate the help. Things get confusing when certain parts are harder to find than others

 

[dyeager535]

The TBI pickups use rubber lines to the sending unit. I always thought it was interesting the Blazers and Burbs have the stainless braided and the pickups didn't. Maybe because the K5/Burb lay on the tank for a longer distance.

I always suspected it being due to the passenger compartment not being separated from the tank.

And the TBI pumps are *lucky* to put out 15psi unregulated, on a good day. One I had could barely hit 14.

However, those braided lines will hold a lot more pressure than a flared rubber connection (same lines were used on TPI @43 PSI) so the common higher pressure pump swap would be a no-no with plain rubber.

 

[1-ton]

Fuel injection hose is rated to 60-PSI. I run fuel injection hose from my senders to the fuel tank selector on my crew cab. I have in tank fuel pumps that are rated up to 60-PSI, but my adjustable fuel pressure regulator is set at 12-PSI. I doubt those sender hoses are seeing maxed out pressure of 60-PSI.

 

[dyeager535]

Fuel injection hose is rated to 60-PSI. I run fuel injection hose from my senders to the fuel tank selector on my crew cab. I have in tank fuel pumps that are rated up to 60-PSI, but my adjustable fuel pressure regulator is set at 12-PSI. I doubt those sender hoses are seeing maxed out pressure of 60-PSI.

Yes, good point, unless you mess around with the pressure regulator, assuming it's running correctly, it shouldn't see anything more than the regulators rated pressure.

I have no idea the failure modes of the regulator, perhaps why GM used "weak" pumps with TBI was so that if there was a blockage, the deadhead pressure wouldn't exceed the connections ability to hold? Obviously that would only be a concern on the rubber fuel line applications, as the braided lines are obviously different.