Fuel Pump Solution - All Failure Modes
#701
EDIT: Got this done. So far so good... To other people reading this. Personally this project was a huge pain, worth it but not as simple as the pictures might suggest.
Last edited by rubberduckie; 04-26-2013 at 07:02 PM.
#703
I was just doing some research here and read through most of this thread and thought I would clarify a few things. For those running Aeromotive 340 pumps, that black stuff you see in the tank and on the pickup sock is from the brushes from the motor in the pump. Eventually the pump will just die. Especially if you run E85. They are also very very poor at hot fuel handling, to the point where they will not move enough fuel to build pressure to maintain idle...
#711
I was just doing some research here and read through most of this thread and thought I would clarify a few things. For those running Aeromotive 340 pumps, that black stuff you see in the tank and on the pickup sock is from the brushes from the motor in the pump. Eventually the pump will just die. Especially if you run E85. They are also very very poor at hot fuel handling, to the point where they will not move enough fuel to build pressure to maintain idle...
Q: Can the 340 Stealth Pump be used safely in e85 and how much HP will it support?
A: E85 fuel has become a viable option for street performance enthusiasts in recent years. It has some very significant pros, and equally significant cons, to consider. It does provide higher octane, and lower charge air temperatures, and is especially popular in forced induction applications, permitting more aggressive combinations of boost, compression ratios and tuning. It is also less costly per-gallon than high-octane racing gasoline. That said, fuel usage increases 30-35% to support equal HP, somewhat offsetting the lower cost and requiring the HP rating of all fuel system components, including and especially the HP ratings of the fuel pump and fuel injectors, be reduced by 30-35%.
A crucial consideration regarding whether or not to run E85 is its tendency to rapidly and frequently contaminate and clog/block fuel filters, resulting in significant flow restrictions, which in turn may damage the engine and/or cause premature fuel pump failure. The reasons for filter contamination problems with E85 include:
E85 is an alcohol based fuel, and alcohols are hygroscopic (attract and absorb water from the atmosphere), which can accumulate in and clog fine filter elements.
E85 is an agriculturally produced fuel and, being a byproduct of plant material, there have been indications some of this “bio-mass” can accumulate in, and clog fuel filters.
E85 has very strong solvent properties, like many alcohol based liquids, which will act to strip accumulated debris and residues from transport and storage containers, and the inside of fuel tanks and fuel lines, which in turn accumulate in, and clog fuel filters.
Aeromotive has conducted extensive testing of the 340 Stealth Pump in E85 fuel, achieving 1,000 plus run hours of service life operating at 60 PSI and 13.5 Volts. In testing, it was found a filter service interval that gave good fuel pump service life required a new, down-stream filter be installed every 10 run-hours. It is vital to understand that a blocked filter creates severe flow restriction of pump output, building excessively high operating pressure between the pump and the contaminated element. If the Stealth 340 is allowed to run in this environment, operating pressures between pump and filter can exceed 90 PSI, creating extreme current draw and reduced cooling flow, resulting in rapid failure of the fuel pump motor assembly.
WARNING: If you plan to run E85 fuel you must be prepared to install proper filtration, and maintain it as frequently as every 10 run-hours. If not, Aeromotive does NOT recommend you the use of E85 with the 340 Stealth Fuel Pump. Aeromotive’s new product warranty assures the purchaser their 340 Stealth Pump will be free from defects in material and workmanship for one year from the date of purchase. Fuel pump failure caused by clogged/blocked fuel filters is not the result of any defect in the pump itself, and is not covered under this warranty.
For a detailed look at post-pump filter options and what a good one should be like, please see Aeromotive Tech Bulletin: Post-Pump Fuel Filtration TB-102 here:
Post-Pump Fuel Filtration | Aeromotive
For a specific example of the issues related to a clogged post-pump filter, please take a moment to see the Case History File embedded in TB-102 here:
http://aeromotiveinc.com/wp-content/...-Case-File.pdf
#712
Hi. This was an awesome article!
I have a problem u may be able to help with.. My 8 won't idle since puttin in a secondhand motor. Have tried all usual suspects inc compression, maf, vac lines, throttle body, ess, plugs, coils, and leads.
A mechanic did a scan and noticed while Idling a fuel system fault message lit up right before the revs increased on their own then CL message (closed circuit we think) then car stalled. Each time it was consistent with same messages in relation to the car idle then stall.. We moved swapped out relays for circuit and fuel among other blue buggers but no fix or change.
Of interest is unplugging the maf creates stable idle?.
U seam to be very knowledgeable in fuel and electrics. What u think I shld try next? Ecu, pump.?
It seems to run great thru the gears and rev range.. Every time I stop, so does the engine!
I have a problem u may be able to help with.. My 8 won't idle since puttin in a secondhand motor. Have tried all usual suspects inc compression, maf, vac lines, throttle body, ess, plugs, coils, and leads.
A mechanic did a scan and noticed while Idling a fuel system fault message lit up right before the revs increased on their own then CL message (closed circuit we think) then car stalled. Each time it was consistent with same messages in relation to the car idle then stall.. We moved swapped out relays for circuit and fuel among other blue buggers but no fix or change.
Of interest is unplugging the maf creates stable idle?.
U seam to be very knowledgeable in fuel and electrics. What u think I shld try next? Ecu, pump.?
It seems to run great thru the gears and rev range.. Every time I stop, so does the engine!
#715
Ok, i'll have to find the harness wiring diagram to compare i guess.
Thing is the second hand motor i popped in had the harness still attached so unless someone messed with it then it shoulda been fine but it was idling bad before i touched the loom.
In any case i swapped the loom out cos my cruise wasn't working either and i plugged all the connectors based on the length and being that my loom had about 200,000km on it the plastic surround was hardened meaning that its quite difficult to plug them in anywhere other than where was intended.
Something else to mention as if this situation isn't difficult enough, when my last engine died at (50,000km, failed bearing) i had taken it in to my regular mechanic because of, wait for it............ BAD IDLE and STALLING. This only occurred to me yesterday as i had assumed the last bad idle was caused by the bearing failure- BUT wot if it wasn't?? Maybe i am just dealing with the same damn problem as i had 3-4 moths ago. Prior to the bad idle back then there was no indication of a failed bearing or loss of power, i just thought it was the coils. Mechanic's thought they noticed something odd with clutch and noise in motor when clutch depressed and that's how the engine saga began.
Thing is the second hand motor i popped in had the harness still attached so unless someone messed with it then it shoulda been fine but it was idling bad before i touched the loom.
In any case i swapped the loom out cos my cruise wasn't working either and i plugged all the connectors based on the length and being that my loom had about 200,000km on it the plastic surround was hardened meaning that its quite difficult to plug them in anywhere other than where was intended.
Something else to mention as if this situation isn't difficult enough, when my last engine died at (50,000km, failed bearing) i had taken it in to my regular mechanic because of, wait for it............ BAD IDLE and STALLING. This only occurred to me yesterday as i had assumed the last bad idle was caused by the bearing failure- BUT wot if it wasn't?? Maybe i am just dealing with the same damn problem as i had 3-4 moths ago. Prior to the bad idle back then there was no indication of a failed bearing or loss of power, i just thought it was the coils. Mechanic's thought they noticed something odd with clutch and noise in motor when clutch depressed and that's how the engine saga began.
#716
Wow. Anyway, I drove on mine for a year, taking it apart monthly trying to find the issue. Stupid me. Luckily I had a friend 1.3 litters of furry who let me try everything above the engine. Didn't help. Oh well runs amazing now.
#717
It should be done more often than that
pretty much any time you do anything related to the engine/drivetrain be it maintenance, simple adjustment/alteration, or major repair
the ESS is a fickle b-tch ...
pretty much any time you do anything related to the engine/drivetrain be it maintenance, simple adjustment/alteration, or major repair
the ESS is a fickle b-tch ...
#718
yup. done it about 20times in the last 2weeks.
plus the odometer reset method.
ive finally booked it into Mazda for diagnostics next week. I also purchased a second hand ecu so depending on wot Mazda find they may install ECU too.
Something else ive noticed and very very rare, i lose POWER like 30% at least (feels like dropping a rotor or like the old days when a secondary wouldn't open) from take off till EXACTLY 6500rpm at which time it kicks like a little turbo and in consistently 6500 every gear!! WEIRD!!! Not sure if its temp related. This car is driving me CRAZY
So to clarify- crap power till exactly 6500 then kicks like back to normal.
plus the odometer reset method.
ive finally booked it into Mazda for diagnostics next week. I also purchased a second hand ecu so depending on wot Mazda find they may install ECU too.
Something else ive noticed and very very rare, i lose POWER like 30% at least (feels like dropping a rotor or like the old days when a secondary wouldn't open) from take off till EXACTLY 6500rpm at which time it kicks like a little turbo and in consistently 6500 every gear!! WEIRD!!! Not sure if its temp related. This car is driving me CRAZY
So to clarify- crap power till exactly 6500 then kicks like back to normal.
#719
#720
So after countless hours researching our fuel starvation issue, and having already modified my siphon assembly and upgrading my fuel pump, I'm still having issues. I can't go below 5/8 tank running at Canadian Tire Motorsport Park (if you don't know the track, watch a video) as the car starves at the bottom of Turn 2. After all my research on various sites, I think I'm going to go down the route of a swirl pot, or otherwise known as a fuel surge tank to hopefully solve the problem.
Has anyone done this with the RX8 that can provide some vehicle specific information? I.E. where to draw power for fuel pump from? Complications with this method?
Any help would be appreciated.
Thanks
Has anyone done this with the RX8 that can provide some vehicle specific information? I.E. where to draw power for fuel pump from? Complications with this method?
Any help would be appreciated.
Thanks
#721
You aren't supposed to modify the siphon system. This was discussed and tried early in the thread, but later discovered to be incorrect. The only exception is replacing the siphon pickup assembly on the RH fuel tank saddle with a second pump, which is a bit of a procedure to convert.
#723
You aren't supposed to modify the siphon system. This was discussed and tried early in the thread, but later discovered to be incorrect. The only exception is replacing the siphon pickup assembly on the RH fuel tank saddle with a second pump, which is a bit of a procedure to convert.
So has anyone run a surge tank yet?
Last edited by ScubaSteve8; 08-27-2013 at 02:23 AM.
#724
Idle
That did help once I reset. I replaced front sensor with spare one and same problems. Disconnected front O2 again and did the reset thing and presto idles again. Though it chewing the fuel and the build up of black on bumper round tailpipes is noticeable.
Anyways, wots it all mean?
Anyways, wots it all mean?