dead oem fuel pump with 42k

[Evolbrz]

ok so my oem fuel pump died I will replace it with a DW65C.. but I want to see if anybody can help me understand what happened.. dont think its normal.

some facts.
*swapped in a EZ30 engine using the stock fuel lines to each bank.
*left evap hose open one middle of the oem fuel hoses.
*the whole evap not running anymore because I dont have the stock ecu anymore.
*driving fuel pump with 40a relay on key switch so it runs constantly.

I need to be educated on how fuel tank venting works because I seen some use check valves etc.. remove pressure on the tank..etc.. I have a gut feeling my oem fuel pump died because of this?? how does one delete evap and make sure tank is vented .. etc..

any help appreciated

EvolBRZ--
2017 subaru BRZ Swapped EZ30
2021 subaru WRX my stock daily

[Ultramaroon]

The fuel pump isn't designed to run constantly. I don't remember specifics offhand but the control unit limits duty cycle to maintain pressure on the single-ended system. No return.

Can learn more via the service manuals. See my sig line.

[Evolbrz]

Originally Posted by Ultramaroon

The fuel pump isn't designed to run constantly. I don't remember specifics offhand but the control unit limits duty cycle to maintain pressure on the single-ended system. No return.

Can learn more via the service manuals. See my sig line.

yes I see pump is controlled by ecu and sending voltage to rpm etc..but it is technically running all the time to provide fuel while driving or idle.. the FPR is in the basquet bypassing gas like a return style does expect it does it in the tank. I dont think it running is the problem ...

[Ultramaroon]

Originally Posted by Evolbrz

yes I see pump is controlled by ecu and sending voltage to rpm etc..but it is technically running all the time to provide fuel while driving or idle.. the FPR is in the basquet bypassing gas like a return style does expect it does it in the tank. I dont think it running is the problem ...

Hmmm... Now I have to review!

I will do so tonight after work. Looking forward to it.

[Evolbrz]

Originally Posted by Ultramaroon

Hmmm... Now I have to review!

I will do so tonight after work. Looking forward to it.

thanks appreciate it.. really stuck dont want to burn the new pump.. If I have to.mod the fuel system I will .. read somewhere guy remove a the EVAP and put a check valve on 2 lines.. one to remove pressure and another to add fresh air ..someting like that .. never had to deal with this with my older bmw 90's project cars lol..

[Ultramaroon]

Originally Posted by Evolbrz

thanks appreciate it.. really stuck dont want to burn the new pump.. If I have to.mod the fuel system I will .. read somewhere guy remove a the EVAP and put a check valve on 2 lines.. one to remove pressure and another to add fresh air ..someting like that .. never had to deal with this with my older bmw 90's project cars lol..

Not much yet. Starting here.

[Evolbrz]

Originally Posted by Ultramaroon

Not much yet. Starting here.

yeah so my only two options...

1. expensive pwm controller for the fuel pump
2. convert to return style

both expensive and second will be a pain in the @$$

[Ashikabi]

You're right that the stock pump assembly has a pressure relief that dumps back into the tank. However the pump doesn't run full speed all the time. You probably wore it out running full speed against a relief valve that couldn't handle the flow. I don't see how EVAP could have anything at all to do with a pump failure. The open EVAP line in the engine bay should be breathing to the outside, since it was originally vacuum. Mine is also disconnected due to LS swap. With no I'll effects.

PS I have a DW65C for sale that I pulled out to replace with a bigger pump. One track day and a few thousand miles on it. DM me if interested

Sent from my KB2007 using Tapatalk

[Evolbrz]

Originally Posted by Ashikabi

You're right that the stock pump assembly has a pressure relief that dumps back into the tank. However the pump doesn't run full speed all the time. You probably wore it out running full speed against a relief valve that couldn't handle the flow. I don't see how EVAP could have anything at all to do with a pump failure. The open EVAP line in the engine bay should be breathing to the outside, since it was originally vacuum. Mine is also disconnected due to LS swap. With no I'll effects.

PS I have a DW65C for sale that I pulled out to replace with a bigger pump. One track day and a few thousand miles on it. DM me if interested

Sent from my KB2007 using Tapatalk

Shoot too bad I already bought one I would of took your offer.

I think this is worth looking at.. just never heard of others having this issue with oem FPR..using High flow aftermarket pumps running turbo. ---You probably wore it out running full speed against a relief valve that couldn't handle the flow---

Reason for the EVAP is becauss my BRZ runs on a standalone and the EVAP I believe needs the stock ECU which I dont have anymore so not sure how the EVAP is releasing pressure or taking in fresh air to the fuel tank... very important things for many reasons

[Ashikabi]

Originally Posted by Evolbrz

Shoot too bad I already bought one I would of took your offer.



I think this is worth looking at.. just never heard of others having this issue with oem FPR..using High flow aftermarket pumps running turbo. ---You probably wore it out running full speed against a relief valve that couldn't handle the flow---



Reason for the EVAP is becauss my BRZ runs on a standalone and the EVAP I believe needs the stock ECU which I dont have anymore so not sure how the EVAP is releasing pressure or taking in fresh air to the fuel tank... very important things for many reasons

Your EVAP is simply not functioning at all right now. My understanding of the system is the purpose is to reduce gas smell when parked, and reduce emissions by burning the fumes via the vacuum line. Your vacuum line is disconnected. So the fumes accumulating in the tank are simply leaking out the disconnected line. You'll get a gas smell when parked. But otherwise there should be no other effects. The tank isn't pressurizing. Even if it did, that wouldn't cause a pump failure.

I'm confident if you're going to run your pump without a controller, you need an external pressure regulator. Since you're operating so far from what Subaru intended those components to do

Sent from my KB2007 using Tapatalk

[Evolbrz]

Originally Posted by Ashikabi

Your EVAP is simply not functioning at all right now. My understanding of the system is the purpose is to reduce gas smell when parked, and reduce emissions by burning the fumes via the vacuum line. Your vacuum line is disconnected. So the fumes accumulating in the tank are simply leaking out the disconnected line. You'll get a gas smell when parked. But otherwise there should be no other effects. The tank isn't pressurizing. Even if it did, that wouldn't cause a pump failure.

I'm confident if you're going to run your pump without a controller, you need an external pressure regulator. Since you're operating so far from what Subaru intended those components to do

Sent from my KB2007 using Tapatalk

yeah good point... I may as well just convert to return style

[Ashikabi]

Originally Posted by Evolbrz

yeah good point... I may as well just convert to return style

Yeah. Maybe there is more to it because of the in tank bypass, but to my knowledge you just need to add a regulator and a return line. You could even use that EVAP hardline and redirect it at the tank to feed back into the basket.

Sent from my KB2007 using Tapatalk