Never ending fuel pump drama

[Murray_Calavera]

So last night pulling away from the lights, I lost power for about 1 second. Bit weird, but I kept driving... 5 minutes later the pump completely dies. When I tried to start the car, the pump won't even prime. 

I left the car for about an hour, tried to start it and it all appeared fine. Pump primed, car started, got the fuel pressure I should have.... Start driving home, 5 minutes later it dies again. I'm stuck in a shit spot this time going up hill with a car right behind me, so I just let the car continue to turn over while praying to the fuel pump gods. After about 2 minutes of turning the engine over, the fuel pump came back to life and I got home (only about another 5 min away). 

So I've been digging around online, it seems like the 525 fuel pumps really don't like to be run at 100% all the time. I've found quite a few examples online of people killing their Walbro 525 pumps within about a year of usage when they are run without PWM. 

So, my pump is an Aeroflow 525 (AF49-1057) and I've been running it at 100% without PWM. I'm thinking the Aeroflow 525 didn't like being run at 100% and has burnt itself up. 

I really am sick of dealing with fuel pump issues, my current thoughts are - 

1. Use a Walbro 450 and run it without PWM. It seems like these pumps hold up pretty well to being run at 100% all the time. I only make about 350kw and can't see me making any more power any time soon so this is probably a fine option. 

2. Get a Walbro 525, run it with PWM. I know doing this will annoy me as I feel like with only 350kw, its extra expense that I don't "need" and I'll be thinking the whole time while setting it up that I should have gone with option 1. I know I'll be happy with this option when its setup and running, its only the initial setup frustration and cost as an issue. 

3. Get a Walbro BKS1001 brushless pump. This is the fu*k it I'm already going PWM, might as well go full retard. This option just seems better in every way, with the only downside being cost. But I don't know much about this pump so I could be wrong. 

Happy to get everyone's thoughts before I go digging around in the fuel tank again. 

[Dose Pipe Sutututu]

Slap a 460L into the car, send its mum.

 

[Duncan]

I know one example is a anecdote not data, but I'm running the same Aeroflow 525 at full voltage through a regular relay, and while I've had other fuel problems including melting the factory fuel hat, the pump itself has been fine for years.

Of course, they aren't *that* expensive these days, you could swap in a new one and see if the issue is resolve.

I think you had a previous thread about fuel problems, have you been monitoring and logging fuel pressure? Is there anything voltage related (for example does the voltage go up when the pressure goes down)

[Murray_Calavera]

32 minutes ago, Duncan said:

Of course, they aren't *that* expensive these days, you could swap in a new one and see if the issue is resolve.

The price isn't the issue, it's how hard my fuel pump is to remove now. I fabricated a custom bracket so my pump sits on the very bottom of the tank (I ran the tank down to 5L remaining to test it, works well). But it is a fkn NIGHTMARE to get the pump down into the tank now =/ words can't describe how much I hate fighting with the fuel pump/hanger now. The other issue is reliability, I'm driving down for WTA in a couple of months, I'd be less then impressed if I was half way to Sydney from Brisbane and my pump fails again =/

The other issue I had was my car battery was slowly failing, with low battery voltage my fuel pump couldn't keep up with what the reg was asking from it. I've replaced the battery and my fuel pressure is back to being perfect. 

As for the low voltage situation that killed my previous battery, I've got a 150amp alternator sitting on my desk waiting to go in. Fingers crossed that will sort that issue. 

[Duncan]

Don't forget to make sure the tank is full to the brim before you try to replace the fuel pump too, that is an essential step.

[Murray_Calavera]

1 minute ago, Duncan said:

Don't forget to make sure the tank is full to the brim before you try to replace the fuel pump too, that is an essential step.

I've got 60L of e85 in there at the moment

[Murray_Calavera]

On 6/7/2024 at 3:43 PM, Duncan said:

while I've had other fuel problems including melting the factory fuel hat

So small update on my current situation.... I've finally been punished for trying to pass 20 amps through the factory connector. It's melted. 

I'm in the process of installing these -  

https://www.efisolutions.com.au/electrical-bulkhead-terminal-submersible-e85-compa

Fingers crossed that's all I need to do to get back up and running again. 

[Butters]

From personal experience, spend the extra and get a frenchies hat with the better connector. 

I've melted those exact terminals twice before upgrading the hat with a proper connector.  

https://frenchysperformancegarage.com/collections/fuel-system-kits/products/copy-of-200sx-s14-s15-r33-r34-twin-pump-in-tank-fuel-system-kit

 

I know its a big step up $$ wise but it will properly solve your issue and give you great peace of mind. 

 

If budget is really stretched then consider this ??(not used myself nor know it will work in your application though)

https://aftermarketindustries.com.au/fuel-pumps-accessories/fuel-pump-power-bulkhead-terminal/

 

 

As an aside run 460s at 12v for over 7 years in e85 no PWM. 

 

 

[Murray_Calavera]

2 hours ago, Butters said:

I've melted those exact terminals twice

Well this is depressing

When the terminal failed, what did it look like/what happened? 

I didn't even realise I had melted the factory connector until I tried to remove it and couldn't. Then looking at it from the inside of the fuel hat, I could see that the internals of the connector had melted. It would be good to get a heads up what to keep an eye out for with the Taarks terminal.

I would love to eventually run something like the FPG setup, but I cant see me installing it with the tank in the car. Very not keen on removing the fuel tank at the moment, I'll probably line this up for when I eventually do my rear subframe bushes. 

[Dose Pipe Sutututu]

I'll PM you 

[Kinkstaah]

4 hours ago, Murray_Calavera said:

Well this is depressing

When the terminal failed, what did it look like/what happened? 

I didn't even realise I had melted the factory connector until I tried to remove it and couldn't. Then looking at it from the inside of the fuel hat, I could see that the internals of the connector had melted. It would be good to get a heads up what to keep an eye out for with the Taarks terminal.

I would love to eventually run something like the FPG setup, but I cant see me installing it with the tank in the car. Very not keen on removing the fuel tank at the moment, I'll probably line this up for when I eventually do my rear subframe bushes. 

I melted those EFI bulkhead connectors as well, best part I did it 1200km from home!

I downgraded to a 340lph pump that draws much less amps and took advantage of being N/A and can use the stock connector. (https://cdn.shopify.com/s/files/1/0414/1681/8852/files/DW300_Tech_Sheet_e20dc539-c1b7-448e-9176-c0da069e1295.pdf?v=1702575698)

In your case, it's time to get the frenchy or other billet setup if you don't want to change pumps. Unless you can downgrade your fuel pump requirements, this is what you must do to fully solve this issue.

[Butters]

 

Melted into the plastic, example one of the two, had washer either side. 

[Kinkstaah]

Yep, that looks very familiar from my Walbro 460.

The frenchy setup is expensive AF. It sucks. Buy once, cry once. Mine took 5-10 years to actually melt... but I don't want to actually do that again. The stock connector took much less time to melt through with the stock plug. I had thought it was fixed for good, and it was.... until it wasn't

[Murray_Calavera]

Thanks everyone for the warnings with this setup. I have the sads but at least I know what I'm in for. 

I'll put the frenchy or radium setup higher up on my priority list now. 

[Dose Pipe Sutututu]

PWM too, less melty

[Duncan]

7 hours ago, Dose Pipe Sutututu said:

PWM too, less melty

Yeah I reckon using PWM instead of full current to drive it would make a massive difference.....for street use there are very few instances (and for a very short time) where you need full fuel flow

[Murray_Calavera]

No punish for a full tank of fuel - so good! Only the connector was dead in the end. 

With regards to PWM, is anyone doing kits with everything needed in them to get you up and running? 

[Dose Pipe Sutututu]

2 hours ago, Murray_Calavera said:

anyone doing kits with everything needed in them to get you up and running?

Kind of, but you'll cry at the price.

https://pure-pf.com/product/maxxecu-pwm-module/

Another option is using a PDM and doubling up the outputs.

Another another option is using a Volvo Fan Relay (PWM, fly back diode, heatsink all in one)

Another another another option (I might do this one day, also has a fly back diode, built in heat sink, will happily run at  5kHz) is the Dorman 902-310

 

[Murray_Calavera]

9 minutes ago, Dose Pipe Sutututu said:

cry at the price

Yep, that's crazy. 

What is the go with stuff like this? 

https://creativewerksinc.com/product/pwm-controller/

[Dose Pipe Sutututu]

3 hours ago, Murray_Calavera said:

Yep, that's crazy. 

What is the go with stuff like this? 

https://creativewerksinc.com/product/pwm-controller/

Looks good but wow the price tag