RX8Club.com - DIY: Installing Series II Fuel Pump in Series I

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- Series I Do It Yourself Forum (https://www.rx8club.com/series-i-do-yourself-forum-73/)

- - DIY: Installing Series II Fuel Pump in Series I (https://www.rx8club.com/series-i-do-yourself-forum-73/diy-installing-series-ii-fuel-pump-series-i-230326/)

I recommend a grease or lubricant on the threads. Helps with installation and removal of the pump ring. Teflon tape may suffice, never tried it though.

Just did this myself. I'm starting to think maybe different years of RX8 had different connectors for the level sensor on the fuel pump, because mine is white while everyone else's seems to be black. I cut a slot out on the S1 connector and it fit fine, even the connectors that you have to stick in the new connector fit perfectly and are not coming out or loose in any way.
https://cimg4.ibsrv.net/gimg/www.rx8...ef27da6e8c.jpg

Did the swap to the series II pump back in 2015 on my Gen 1 2008 40th Anniversary Edition RX8 and it has worked perfectly ever since. Followed the DIY here in the club with the minor modifications recommended. Cheers

Did this swap to my 05. Anyone else level sensor stop going down at aroudn 1/4 of tank. Car sat for a while before i replaced this pump to finish a rebuild.
Used the ford 3/8 - 5/16 kit and im getting gas, I filled it a bit earlier and it read around half a tank.
It doesnt seem like there is a flow issue as after being tuck on 1/4 tank for a while it ran out of gas.

Any suggestions.

Check the wiring for theevel sensor...

There is one in the passenger side and one in the drivers side that add up to give the value. If the drivers side one got damaged it won't read correctly on the low end of the fill

Great upgrade S2 pump on S1

Would recommend to swap the filter and completely clean hoses before installing if purchasing a used one , the seller used to premix so the filter was dark and worn with 75k on it got one for $125 with the connector I’m impressed how it responds much better considering I also have the S2 tranny

Quote:

Originally Posted by dannobre (Post 4968370)

Fixed the issue. I needed to trim more off quick connect side of the line. Pump works and getting constant fuel pressure. Now I need to figure out why I keep getting a random high rpm/load misfire

noob question. Is the S2 fuel pump basket better than the S1 basket? is that why you guy are swapping the whole assembly over? I was just going to swap in a bigger fuel pump but I would rather get a better basket/assembly as well. Thanks

Quote:

Originally Posted by 5t341tH (Post 4979579)

Defenitely better throttle response at high rpm’s doesn’t starve , I’m getting a better cold start in the cold mornings , 6 months still running better than the S1

Quote:

Originally Posted by pfknrx8 (Post 4979580)

Defenitely better throttle response at high rpm’s doesn’t starve , I’m getting a better cold start in the cold mornings , 6 months still running better than the S1

Thanks. I'm not referring to the pump itself. I was asking if the S2 basket has better designed baffling over the S1

Quote:

Originally Posted by 5t341tH (Post 4979581)

Thanks. I'm not referring to the pump itself. I was asking if the S2 basket has better designed baffling over the S1

the s2 basket is better designed and allow more fuel to enter the basket. i was able to run lower fuel level before getting fuel starve on track. i also drilled out the feed hole at the bottom of the basket to allow more fuel in.

Quote:

Originally Posted by 5t341tH (Post 4979579)

In one word, yes, it is better, Swap out the entire assembly, as every part is improved over the series one pump. I have seven+ years on my swapped in series two pump on my 2008 40th Anniversary Edition RX8 and it has worked flawlessly, even under high use conditions.

Cheers

The parts aren't readily interchangeable between the S1 and S2 fuel pump modules, or at least not without doing a bunch of custom work because they're entirely different designs.

So swapping out the S1 module for the S2 module and making fewer mods to accomplish it is the logical choice.

There's no difference in general running performance though if the pump module is operating properly. The problem on the S1 module is the main filter isn't replaceable, but is on the S2 module. Some people may just swap out the pump and not realize that the filer was plugging up. It was never intended for the S1 pump module to be serviced this way, but they revised that with the S2 module. If you notice a running performance between them other than the low fuel level cornering at high G load scenario then the likely reason is the module was failing.

Here's the S2 pump module thread that details it out: https://www.rx8club.com/series-ii-af...thread-261755/
.

Quote:

Originally Posted by olddragger (Post 4209890)

man that is a good write up---points on all the work it took to do this.
Glad it worked for you and mine is still going strong after a few years.

Thanks for the information. We race this weekend at Carolina Motorsports Park. And I don’t have time to fix it before then. The next week we race at Sebring. I will make the change before then.

Quote:

Originally Posted by etzilon (Post 4621731)

I just got a series II pump in place on my series I; it went very smooth thanks to this write-up! Thanks to those that have contributed.

For the fuel line that goes to the other side of the tank, I used an AutoZone fuel line repair kit - FORD 3/8" quick connector with 5/16" nylon hose.

Reusing the Series I pump connector is a brilliant solution. It will be obvious once you disassemble everything but the connector that's referred to by Skywalker is the one that connects the fuel pump to the fuel pump assembly. I just used a razor knife to make the slot. Getting that actual wires/terminals off is easy; just insert a small flat screwdriver perpendicular to the wire between the wire and the gray plastic tab that runs parallel to the wire.

One note on the fuel bowl design: It seems as if (note the "seems as if") the siphon system is designed not only to pick up fuel from the right side of the tank but also from outside the bowl (near the bottom). On the Series I assembly, the bowl fills up only by a small hole with an orange rubber "float" at the bottom. My thinking is that the bowl refills quicker with the Series II design.

When you used this kit did you have any issues with gas gauge reading properly?. And how did you bend you line?
I did this and the line worked for a bit but ended up making it so below 1/8 of the tank I can read my gas Guage and it wasn't sucking properly from the siphon side.

I tried to fix it and it worked for a bit but then jacking up the car from passenger side must of moved it just enough to kink the line or mess something else up. My connecter from the other side is reading properly with the fuel gauge though I will take that side off to check the siphon didn't move at all

edit: I checked the connector and it was kinked right after the connector. Redid the line a bit to fix the kink. If this doesn't work I'm going to use the extra 5/16 line and get a right angle 3/8 quick connecter as the line shouldn't have to make a u turn to get to the otherside.

Quote:

Originally Posted by marcx987 (Post 4985078)

When you used this kit did you have any issues with gas gauge reading properly?. And how did you bend you line?

I had a big advantage... I took the tank off the car.

Quote:

Originally Posted by etzilon (Post 4985150)

I had a big advantage... I took the tank off the car.

Lol yea I can't /don't want to do that.
though I finally made a proper hose. Just bought a 90 degree 3/8 to 5/16 adapter and used the extra hose from the Ford kit.
Though now I need to replace the level sensor on the driver side. It intermittently works then shits the bed at 1/8 of a tank.
I had to basically take it out the tank and table test it to figure it out. Cuz it worked properly most of the time.