Hey everyone,

Can anyone advise me on how the crossover line in the fuel tank in removed? I'm talking about the venturi suction line from the fuel pump housing to the passenger side of the tank. On the passenger side, there's this little screen that is hooked to the bottom of the tank. How do I remove it from the bottom of the tank without damaging anything so I can reattach it later? Picture of what I'm talking about below.

Thanks!

 

Is that from a 2009+ S2?

If you have the tank open I’m in need of the ID dimension on the fuel tank opening.

 

That image is, but I have a S1. Though I was in there and that crossover line looked just like that. I didn't have the big dummy assembly on the passenger side that I was expecting to see. I'm the original owner so it wasn't changed out without me knowing.

What do you need the measurement for? How accurate do you need it to be? Would the S1 measurement work? It's probably the same size seeing that the fuel pumps are compatible.

 

The S1 is different and comes out like the fuel pump module, except from the top piece there is a metal rod/shaft extending down from it and the pickup is a sliding fit on the shaft and secured on by a c-clip on the far end. There is also a spring on the shaft between pickup and the top so when the entire assembly is installed in the tank the spring is compressed and pushes the pickup against the tank bottom just like fuel pump module. The nylon siphon tube that goes across the tank between the pickup and pump module has a rubber hose clamped between it and the pickup. So you you remove the threaded ring, lift the entire top/pickup assembly, unclamp and pull the rubber hose on the crossover line off the pickup , and then it comes out just like the pump module. Pretty sure I have some pics, let me look.

 

ok, this is from the S2 pump install thread; pics don’t display there so you have to click on the web link to see them.

So this is the pickup, you can see the rubber hose attached to it from the crossover siphon tube and on the upper RH a bit of the shaft that extends down from the bottom of the top piece and the spring that puts downward pressure on the pickup to keep it against the tank bottom. So you take the ring off, lift it up out of the tank just like this, unclamp the rubber hose and pull it off the pickup barb, and then you have it out.





so if you haven’t taken the float out yet, it’s held on the tank bottom by tabs off the bottom that require twisting the float assembly 1/4 turn to either secure it to the bottom under the tabs or to release it from under the tabs to then remove it out of the tank.

so one other thing this taught me; see how the rubber tube attaches to the siphon pickup, when you do the S2 pump module conversion installation, the fitting on the S1 siphon tube is a different size than than the fitting on the S2 pump. So we were all cutting off the S1 fitting from the siphon tube and then installing the disconnect fitting needed for the S2 pump module, which is a pitb to do it like OE using the special nylon fitting tools. Instead of doing that, you need a short piece of 5/16” ID submersible fuel hose, cut the fitting off the siphon tube, slide the rubber hose onto the siphon tube and a hose clamp or two if you prefer and clamp them down, and then you can put another hose clamp over the hose, and install the 5/16” hose barb x 3/8” disconnect fitting on the hose end.

So you’re attaching the siphon tube to the pump module similar to how it attaches to the pickup tube just with the disconnect fitting. It will be a lot easier that way. It only sees light suction to pull fuel over from the other tank saddle. so the connections just need to be tight enough so it’s not sucking around the connection joints. It’s not like a high pressure connection so I’d skip putting a quick disconnect fitting on the siphon hose and instead use the submersible fuel hose and stainless steel hose clamps

 

as far as the fuel tank opening dimension goes, I need to know how big in diameter can fit into the tank opening. I looks like the seal on top might be a bit tighter than the actual opening on the tank from this picture. So whatever that measurement is.






from when I had the tank out and cleaned all the grime off

 

First off, thanks for all the info here Team.

I had already read through the entirety of the S2 fuel pump swap thread, so had already planned on what you had mentioned. I also saw your post there about the S1 passenger connector working for this swap and not needing the S2 sending unit. I wanted to verify this so if it wasn't true, I could get the right parts before I get into the swap and don't have what I need. So a couple day ago I opened up the passenger side of the tank. What I found was just a lid under the lock ring. No spring-loaded assembly, nothing. Just a flat lid with the sending unit plugged into the underside of it and the pickup line hooked to the bottom of the tank (the siphon line looked like the picture of the S2 one in my original post).

Now, I am the original owner of the car. It's a 2006 GT AT (6 port) and has 42,000 miles on it. Nobody has been in either side of the gas tank for any reason. I haven't had the lock ring/seal recall done yet. The paint marks from the factory on the lock rings lines up with the marks on the tank and none of the dirt/grime that gets stuck in there was disturbed (no fingerprints, scuffs, nothing). My rear seats hadn't even been removed, as I found several pieces of the plastic seat cover that they rip off before delivery. So why would my tank have this setup?

In addition, I then unplugged the sending unit plug and tried to plug it into the S2 fuel pump lid and the plug wouldn't fit. It was "backwards" like the one on the driver side is. So I have no idea what the heck Mazda did when they built this car, but it isn't "normal", at least according to all the forum posts that tell me what it should look like. It also doesn't match the part schematics from the Mazda parts lists.

Now I realize I'm just some random idiot on the internet, but I know what I'm telling you is 100% correct.

I don't have pictures, but I may try to get some when I get to doing the swap once all the parts get here. Until then, any speculation you have is welcome.

FWIW, I have the crossover siphon line from a S2 that I'm planning to just clip to the bottom of my tank and hook the the S2 pump housing, seeing as how I must have those clips in the tank. I was going to route it to the S1 dummy housing on that side, but I don't have one of those, so that plan is out the window.

 

Yeah, maybe I got that connector wrong. Had a lot going on at the same time and maybe was confused. So I just got rid of that rather than mislead anyone. My picture is from a 2005. So I’m not sure if they changed the pickup design or if that’s an automatic thing or what. It looks like what I saw in a parts diagram for the S2 fuel system

 

Yeah the whole passenger side looks like the S2 diagram, which seems really weird to me. They didn't have 2009 parts in 2006.

 

unless someone swapped in an S2 tank I’m not sure 🤔

 

I can guarantee you that tank has never been dropped. I'm at a loss.