Fuel System layout/ diagrams

[C.Plavan]

Hey Guys-

As this is my first venture into a non-carburetor car, and my first ever Subie motor- I need some help.

I will be hooking up a Fuel Safe racing cell (In tank fuel pump) with -8AN lines.

Is there a diagram, or can someone educate me on the fuel lines going to the EJ25 motor. Return lines also etc. I just need to know about the motor, then I can figure it out.

Any trick parts that I should know about would be helpful also.

[Goldwing]

image.jpg

I had an '07 where the three fuel lines coming off the top of the engine were in a different order ( than the pic) with the top line still the delivery line, the middle line a return line, and the bottom line the purge line. You can quickly determine the two fuel lines by the pressure regulators along those lines. I'm still working on what is needed to reproduce the purge/fuel tank vent system. Many are tracing the purge line back to the purge valve under the intake manifold, and removing the valve and finally plugging the resulting hole in the intake. Look into the thread type , someone pointed out that it isn't NPT, but something similar sounding like SNPT or something. Obviously, you want it sealed. You can then vent straight to atmosphere or through a charcoal canister to control fumes. Hopefully a start. It's as far as I've gotten, I'm buried in wires at the moment, lol.

[Mechie3]

The two little saucers inline aren't regulators per se but dampers to prevent sudden spikes in flow. The FPR itself is after all of the injectors and has an airline hooked up to it. It is a 1:1 rising rate FPR. The pic is from a legacy GT which uses a slightly different manifold and side feed injectors. WRX motors use top feed injectors. Overall flow is still the same.

Tank - filter - inlet of fuel rail 1 - outlet fuel rail 1 to inlet of fuel rail 2 - outlet of fuel rail 2 to FPR (bolts to fuel rail in stock config) - FPR to tank return

Or, you can have it come from the tank, split into a Y, feed both inlets of both fuel rails at the same time, then have them feed back ito a FPR and back to the tank. This is more common on aftermarket setups.

[C.Plavan]

Thanks for the help.

I'll probably do the aftermarket setup.
Since I bought the motor separately, I'm guessing I'll need to grab a single FPR- or is it already on the motor? ( I'm on a business trip and can't run out to the garage and look.). Routing it this way would only require one FPR correct?

[Mechie3]

Both ways only require a single FPR. The OEM regulator bolts to the fuel rail and the fuel feeds all injectors in series. Aftermarket tends to be parallel so the FPR has two inlet ports but a single outlet/return to tank.

[longislandwrx]

Most aftermarket rail kits reuse the regulator and you end up bolting it onto the distribution block.

[C.Plavan]

Alright- So I got my Fuel Safe cell. I just want to make sure I have all this right. I'll be using the stock FPR for the time being. I'm guessing its under the manifold (passanger side?) I'm use to Carbs- not this fancy stuff.



Top line is supply line (I will run it from fuel cell (in tank pump) to filter, then to top rail) I will be using AN fittings and braided lines.
Middle line is return line (Run it back to the tank)
Bottom line is vent line- Since I am not running stock tank or canister, should I just run a line with a small filter on it? I'm unsure what to do with this one, what have you guys done?

Let me know if I'm way off base here. I'm getting ready to order all the fittings and hose.

[Mechie3]

Remove the vent line and delete the solenoid assembly hanging on the manifold. Plug it with a bspt plug. Also plug the line on the turbo inlet where the solenoid used to go.

[C.Plavan]

Thanks Mechie. Excuse my noobness with these motors. I do better with pictures. I'll search around, or if you can find one quick on google post it here.

[C.Plavan]

I found this- Is this correct?

[Mechie3]

Sort of. Delete all of that including #2. It vents the charcoal canister at certain times while driving. No canister, nothing to vent, no need for it.

No problem with the noobness. I was a subie Noob back in 06. If I built something with any other motor I'd be a Noob too.

[C.Plavan]

Thanks- You wouldn't happen to remember the BSPT sizes off the top of your head? I need to order those. If not I'll just order a bunch of different ones.

[Mechie3]

1/8"? I ordered a couple sizes too. Don't remember which ones I ended up using.

[07FIREBLADE]

Is there anyway to delete most of the emission junk at the front of the motor with the stock tank and keep the charcoal canister? Like delete the purge solenoid and just run hoses or some other solution.

[Mechie3]

You'll end up having the canister but just venting that to the atmosphere and not feeding it to the I take manifold.

[C.Plavan]

So I removed this Spaghetti.


Now I need to plug the holes.

Mechie- The BSPT does look like a 1/8" on the center. I'll have it here any day.





Do I plug this one (on left)? Or run a hose somewhere?

[Mechie3]

Plug the inlet to the silicone tube. Remove the threaded barb on the manifold and plug it. I think the bent fitting is pressed in. I believe I just capped it and zip tied the cap in place. Save the spaghetti. It breaks often and people are usually looking to buy them. Quick $20.

[C.Plavan]

Plug the inlet to the silicone tube. Remove the threaded barb on the manifold and plug it. I think the bent fitting is pressed in. I believe I just capped it and zip tied the cap in place. Save the spaghetti. It breaks often and people are usually looking to buy them. Quick $20.

Thanks again! I'm sure I will have more questions when I get ready to fire this thing up.

[longislandwrx]

Looks like you are on your way.

For a better look, you can remove the hard line under the manifold if you want, I think it can be done without removing the manifold if you are creative with the snips.

[suttonb3]

I could use some help identifying which fuel lines are which. The FSM for my '06 WRX says the top is return, the middle is vent, and the bottom is delivery. The Factory Five manual says that the top is delivery, the bottom is return, and there is no middle. They say to run the vent line from the tank to the engine bay. Looking at it, I think top is return, middle is delivery, and bottom is vent. The bottom must be vent, the line was only secured with a hose clamp and it has no damper valve. I think the middle is delivery because it crosses over the engine to the fuel pressure regulator on top of cylinder 1. It seems like that should come first, but I really don't know. Also, the return line is supposed to be 1/4"? I have pics, but they won't upload right now for some reason. I'll get them up as soon as possible, but I have a feeling that this is a really simple solution for you seasoned guys. Any help is appreciated!

[Bob_n_Cincy]

I could use some help identifying which fuel lines are which. The FSM for my '06 WRX says the top is return, the middle is vent, and the bottom is delivery. The Factory Five manual says that the top is delivery, the bottom is return, and there is no middle. They say to run the vent line from the tank to the engine bay. Looking at it, I think top is return, middle is delivery, and bottom is vent. The bottom must be vent, the line was only secured with a hose clamp and it has no damper valve. I think the middle is delivery because it crosses over the engine to the fuel pressure regulator on top of cylinder 1. It seems like that should come first, but I really don't know. Also, the return line is supposed to be 1/4"? I have pics, but they won't upload right now for some reason. I'll get them up as soon as possible, but I have a feeling that this is a really simple solution for you seasoned guys. Any help is appreciated!

fuel lines.jpg hoses.jpg

On the engine, the top (5/16) is delivery to the engine, from the pump and filter.

The middle (5/16) is return to tank.

The (1/4) on the bottom is a vacuum line used to purge the charcoal canister. DO NOT ATTACH THIS TO THE TANK VENT, iT WILL CAUSE THE TANK TO IMPLODE. On the 818 just put a cap on this 1/4" tube unless you are installing the Evap system.

On the engine the fuel regulator is actually after the injectors.

I thought the instructions that came with the new tank were confusing.

Hope this helps.
Bob

[suttonb3]

Thanks so much for your reply, Bob. The instructions that came with the tank (1N) were really confusing. Factory Five has done a great job breaking down the instructions for the different donors, but I don't think that was done here. Their donor only has 2 lines on top of the engine (mine has 3), an external fuel filter (mine's in the tank), and no mention of what to do with the fuel dampers (the little black saucers before the intake, mine has 2). I called tech support yesterday and was told that I was the first call about the new fuel tank and he had not heard of any issues.
When you say to cap the evap line, you mean on the tank and on the intake? Doesn't the tank need some sort of breather to prevent a vacuum?
I wanted to delete the evap system for simplicity's sake and no need to pass emissions, but I've heard that can cause some pretty bad gasoline fumes. Since she'll be parked in my attached garage I want to avoid that but would happily rip the system out if the fumes are tolerable. Anybody have experience with this? Capping off the vent line on my fuel tank would also help with my next anticipated issue: the vent line getting kinked when the fire wall is installed.image.jpg image.jpg image.jpg

[wleehendrick]

I wanted to delete the evap system for simplicity's sake and no need to pass emissions, but I've heard that can cause some pretty bad gasoline fumes. Since she'll be parked in my attached garage I want to avoid that but would happily rip the system out if the fumes are tolerable. Anybody have experience with this? Capping off the vent line on my fuel tank would also help with my next anticipated issue: the vent line getting kinked when the fire wall is installed.image.jpg image.jpg image.jpg

You don't want to cap the tank vent, just the evap line on the motor; the tank needs to vent or pressure will build up (and also let air in to displace the fuel used). I'm in the same situation with an attached garage and plan on adding a small charcoal canister like others have done. The charcoal absorbs the gas vapors (activated carbon has lots of surface area, which is why it makes a good filter). In a full evap system, the canister is periodically purged by a solenoid. With an un-purged canister, the charcoal may eventually saturate. I don't know how long this will take, but I wouldn't mind changing out the carbon every year or so (hopefully less) to avoid the complexity of the OEM evap system and keep fumes out of the garage.

[Bob_n_Cincy]

You don't want to cap the tank vent, just the evap line on the motor; the tank needs to vent or pressure will build up (and also let air in to displace the fuel used). I'm in the same situation with an attached garage and plan on adding a small charcoal canister like others have done. The charcoal absorbs the gas vapors (activated carbon has lots of surface area, which is why it makes a good filter). In a full evap system, the canister is periodically purged by a solenoid. With an un-purged canister, the charcoal may eventually saturate. I don't know how long this will take, but I wouldn't mind changing out the carbon every year or so (hopefully less) to avoid the complexity of the OEM evap system and keep fumes out of the garage.

Cap the evap line at the motor like wleehendrick said. Or you can remove all the purge valve and hoses from the motor. There is a thread about simplifying the motor.

I used SS braided rubber hoses for my fuel and return line. The hoses seemed to smell for the first couple of weeks, but nothing anymore.

In your second and third picture, it looks like your vent line is going to the motor.

Also, don't put you vent line anywhere near you exhaust manifold.
Bob

[suttonb3]

Thanks so much for your patience and guidance. On to the next challenge!!

[John H]

Hi All-
Just got my evap line question answered above and avoided a new thread. Searching is good.
Will someone please point me at a source for the 1/4" evap line cap part and other "one of" items.
Thanks