Fuel lines ?

[1989]

I'm sealing a 302 into my 84 ranger and it's fuel injected my previouse motor was carb is it ok to run high pressure rubber fuel lines from the motor to the new tank or do I need to install the hard lines from a fuel injected vehicle ?

 

[jmcleek]

Other who are more knoliagable than me can chime in but being that it is a 84 with a steel tank knot set up for efi there is more than likely more than just the lines that need to be changed. to began with early efi trucks had 2 fuel pumps , a 6 psi in tank and a 60-90 psi on the frame rail and a surg tank with both feed and return going through it .This is because there is no baffuls in the tank to help keep the intank pump supply with fuel in stop ,start ,and cornering on a partshal or low tank. If you don"t have a way to keep the high pressure pump supplied with fuel in the befour stated monovers you will have stalling when the pressure drops . I would use hard lines if all posable ,and high pressure hose, double clamped where needed.

 

[Tedybear]

I'm going to agree with JM. If for no other reason then safety. You'll need a total of 3 lines. Pressure, return, and vent for the emissions. You can do this pretty easy using bulk steel tubing of a large size for the pressure and return..and a smaller line for the vent line.

Double clamp is a huge must on the pressure line!!! The return line isn't under much pressure as it is mainly volume. (It will dump out a side port normally built in/at the fuel pump in tank. It might be worthwhile to check into places that can custom make replacement fuel hoses with fittings that can be made to mate into place with the steel line at the transition points (rubber hose from the steel line to the regulator/injector rail, same for the return line...and one for the pressure line at the fuel tank to the steel line.) A true parts house should be able to help. (our local NAPA can custom make most rubber hoses with high pressure fittings.)

Best of luck with it! And stay safe when working with the fuel system.

S-

 

[JoshT]

To answer your question. Yes you can use rubber lines no problem, just make sure it is hose rated for fuel injection. I wouldn't worry with double clamps unless the attach point doesn't have a barb or flare to help bite, and use fuel injection hose clamps where they are used. IMO if you are reusing sections of hard lines, rent a flaring tool and put a bubble flare where you cut the tube, this ill five the hose and clamp something extra to bite onto. You will need to be careful with routing the rubber hose to make sure it doesn't rub against anything. That said if you are going to run hose I would recommend steel braided hose for the added protection, and clamp it to the frame rail. Hard line would of course be best but it isn't feasible for everyone. Personally I'm using a mix of hard line and rubber hose to plumb my truck, if I could get ni-cop tube in sufficient quantities locally I'd use that instead. Since I may need larger line with my planned future engine rebuild I'm going to save it for then.

Many Rangers actually used a rubber or nylon (I think it's nylon) hose straight from the factory. I know that my 86 had factory nylon for the whole system when I tore it apart, was still in great shape when cut it up and I pulled it out. If you want to get hard lines from a Ranger to swap in, you will probably have to look at the later (but pre-98) Rangers not sure which or if any had a return fuel system so you may actually have to scavenge multiple vehicles to find what you need.

As for everything else those guys mentioned, we have no way of knowing what your fuel system is. Come on guys, he has given us no info about his system other than EFI and "new tank". I stress that last parts because you keep trying to coach him through a fuel system as if he were using all the stuff from his 84 Ranger. If he has any other questions about his fuel system he'll ask.

to began with early efi trucks had 2 fuel pumps , a 6 psi in tank and a 60-90 psi on the frame rail and a surg tank with both feed and return going through it .This is because there is no baffuls in the tank to help keep the intank pump supply with fuel in stop ,start ,and cornering on a partshal or low tank. If you don"t have a way to keep the high pressure pump supplied with fuel in the befour stated monovers you will have stalling when the pressure drops .

Yes the early trucks did have two fuel pumps but not a surge tank. I think that what you are actually referring to is the fuel reservoir. It had nothing to do with baffling in the tank or fuel movement during cornering. The low pressure pump in the tank existed for no purpose other than pulling fuel out of the tank and sending it to the high pressure pump. This pump pulled fuel from the bottom of the tank so as long as you have fuel in the tank it has a supply of fuel. Fuel was then sent to the reservoir, which on some models also housed a fuel filter, and then to the high pressure pump. The purpose of the reservoir other than filter was to protect the high pressure pump. The low pump was high volume, low pressure while the high pump was lower volume, higher pressure. The main reason for having two pumps back then was because high pressure pumps sucked at sucking. You needed the low pressure pump to pull fuel out of the tank and the high pressure one to pressurize it. The low volume pump supplied more volume than the high pressure pump needed. So the reservoir existed to hold a supply of fuel for the high pressure pump and returned the excess fuel back to the tank along with the return fuel from the engine. With improvements in pump design they were able to eliminate the low pressure pump and moved the high pressure pump into the tank, this also kept the pump cooler allowing for a longer service life. With current pump designs you can get a high pressure inline pump that has no need for a low pressure in tank pump.

If this were a race car you'd be on to something with the baffling, but it isn't and almost no normal production vehicle on the road today has baffled fuel tanks. Sure there are cars with a racing inspired background that may have them, but even most of those don't. Baffled tanks are pretty much reserved for aircraft and aftermarket tanks.