If these pumps are failing - how come no-one ever posts about it ?

 

There was a post about the Walbro's failing a while ago by MM. It seems, from what I read, the impellers burn up when you run the car low on gas. He said that Walbro doesn't want to talk about the problem.

 

I replaced my OE pump with a Walbro from Ray and it lasted maybe 20-30 min on a 1/2 tank of gas. Yeah Walbro has/had issues with the pump.

 

Yeah, it seems supply was ramped up to demand by cutting corners.

There is actually a raging discussion going on in the Cobb PROTuner circuit about fuel pumps right now.
It seems quite a few shops were bitten by some weird bit of chicanery on the part of Walbro and their supply chain.

 

yeah, life isn't always so simple but supposedly it has already been done on an RX-8

You can always gut the OE regulator, plug/cap it, and use an external bypass regulator instead.

Aeromotive makes the fittings that will allow you to plumb one in between the pump housing discharge connection and the external fuel line fitting. I would look at plumbing an external regulator in there, tapping a fitting into pump housing top plate with a tube running down from it on the tank side to the bottom of the tank, and plumbing the regulator bypass discharge back into the tank there. Not as simple or as clean as the OE regulator (which IMO is a cheap, crappy design anyway), but simpler than putting a bypass at the fuel rail and plumbing it all the way back to the tank.

there are other alternatives, like using a resistor setup to drop the pump voltage and control the pump output that way instead similar to the OE one for low engine speed fuel pump control; the only limit is your imagination and skill

 

Yes. It has.


Except that the saddle tank siphon would stop working.

 

I did fail to account for this, but it could be accommodated on the bypass return, it is just more work and not really that difficult

I like the voltage control idea better though an external regulator usually has a boost compensator nipple for FI applications

 

how about routing the bypass back to the siphon assembly in the same manner as the OE regulator?

 

Easier way is just two pumps, return rails and a regulator.
No guesswork.

 

Some trivia on OEM Fuel Pumps..

The Series 2 uses the same Sock Filter as the NC MX-5, CX-7 and 9, Mazda 2, 3, 6 and MS6,
and same Pressure Regulator as the NC MX-5, CX-7, Mazda 2 and 6.

The main difference is the Pump Motor in Series 2 (which is new and not used in any other OEM fuel pumps).

As we know for Series 1, RX-8 Fuel Pumps "officially" Mazda don't sell or list individual parts.
.

 

To this point, the Series I fuel pump shares a motor with the Evo 8 and 9 made by Arram.
The Series II shares a motor with the Evo X, made by Denso.

 

I havent had a problem with the s2 pump for a few years now. it seems to be holding up OK. Of course I am not at the h/p levels some of you others are and I am not as fine tuned in regards to fuel pump pressures either. I probably should be!
But for an oem injector set up/build it seems to be ok?

I wonder if the s2 denso pump would hold up to a voltage controller such as a CB"Boost a pump" thing? Has anyone looked into replacing the pump in the s2 model?

 

All this pump talk is confusing the Hell out of me. I know everyone is trying to find a solution. At the moment my car is down were every thing is easy to get to.

I know "manic" says the easiest way is just two pumps, return rails and a regulator... since I don't know a lick about fuel how would I go about plumbing something like this up..


__________________

 

fuel supply is dependant on what you are trying to do?
If you are building using oem injectors there is no need for a higher flow pump? For more reliability the 09 set up seems to be the best at present?

 

this would be for a turbo setup for upgraded injectors as well as reliability. Just wana do it right the first time

 

What is the lph fuel pump of rx 04 model?

 

if you read the first post, you'd know it's a 115 lph by Arram.

 

o i thought i was for 09 model can i use walbo 255lph fuel pump in my rx8, i only mod the ign inatke and exhaust..

 

Unless your having an issue, there isn't any reason to perform the mod. The oem pump isn't holding you back.

 

I'm trying to find out I can. Perform the mod myself

 

as I'm reaching 50k miles now, do you think its a good idea to switch out my fuel pump?

I'm not going boost crazy just running at 8psi ish but with a well flowed exhaust and hi flow cat, and new Pettit prepped engine

 

I'm so confused now too. I bought a Black Halo complete fuel pump upgrade assembly last nov. and just getting ready to do some installs. Are you now telling me the pump is a mistake? or some people just have issues and others don't.

 

The latter.

Ray would be better to speak to the issue than I since he knows the numbers, but I just had my own concerns about Walbro recently and he felt it would be better to pull the pump assembly from the market and figure it out at our end, rather than possibly facing failures in the field.

I'll have a more detailed report in the near future.

Until then, I can say with fair certainty that you are unlikely to face and issues.

 

Y'all know that Walbro be made in China, right?

 

Yes.

In 1998, Walbro sold their name to Ti Automotive, rendering the entire crapstorm about "Chinese fakes" moot and a red herring.
All Walbros are, essentially, fake.
Honestly, I don't know how they got away with "Made in the USA" stamped on the side for so long, but that has stopped, too.
I didn't discover this fact until fairly recently. After getting slapped around by Walbro's biggest distributor in North America for being to vocal about the "Chinese fake problem", I started doing some research and learned their dirty little secret.

Now just because something is made in China doesn't necessarily mean it's crap. In fact, there really isn't any choice left since ALL fuel pumps, from every manufacturer and in every application are now made in China.
Yes, Bosch is made in China, too. As is Denso, Holley, Aeromotive and Deatschwerks.