[Scott65]

Fuel pressure issues resolved with new pump. I flowed it out of a small container with 3 ft of discharge hose, then again through the full system in the car. No difference. Almost a half a gallon in 15 seconds. Measured the side of the can with a tape measure both times, as the container wasn't finely graduated. Old pump wouldn't put up what it was rated at through the 3 ft hose, and was down to about 25% through the entire system. Test drove it tonight wide open throttle holds 300 kpa, as it's set, during brief throttle stabs. Seems good to go. Now on to the new lines and adding in the ethanol content sensor. After this unwanted distraction...

[Tom Vaught]

Very Happy that you have resolved your fuel issues, I added a 3/8" second fuel line on my GTO (chevelle line actually) on the passenger side and have a 1/2" return line back to the tank. That is probably overkill for what I will be doing with the car but easy to do if the tank is dropped and the car is on a lift.

My 400 liter gas pump will come out when the hoist is free.

Tom V.

[Scott65]

Tom, I have -8 supply and return. I will be replacing it soon with the same size, but teflon lined. An interesting observation: the ID of the pump is around .220. I used a short run of 3/8" stainless tubing on the supply side to get down and away from the top of pump assembly. Since its bigger than the pump ID it doesn't bother the flow, and puts the connections in a place that's easier to get to for installation/removal. Which I hope won't be for a long time now.

[Formulajones]

So it was a faulty fuel pump? That's good news and easy fix.

[Tom Vaught]

Apparently, the same symptoms as my two vehicles prior to both of them dying from the 15% ethanol in the fuel and the old design 255 liter/hr production pumps. The fuel pumps in both vehicles worked but you could tell a difference in the performance before they died.

Tom V.

[Formulajones]

Weird, I've used a bunch of the 255's, 190's, and a couple of the 400LPH pumps, that have been in service for years on ethanol pump gas and no issues to date.

Sounds more like to me he just got a faulty pump from the get go since it didn't work right off the bat and didn't have all that much run time on it. Don't think ethanol is that quick to react.

[JLMounce]

Glad to hear that you got that sorted. Sucks that it was a bad pump, but also good to hear that was likely the only case. Sounds like the tank is doing it's job now.

[Scott65]

I believe it was faulty. I went with the 450 as replacement, since I had to, and intend to try E85 at some point. Probably summer time. Another interesting observation, as soon as I hit the switch, the pressure was 21 kpa higher than with the old pump. I had to adjust it back down to 300 kpa. Now when it's running it's a little higher than the 100 kpa differential where before it was lower. Eg, 280 kpa @70 map, before would've been 260, maybe 255. The 400lph was just bad for whatever reason, from the get go.

[Tom Vaught]

Originally Posted by Formulajones

Weird, I've used a bunch of the 255's, 190's, and a couple of the 400LPH pumps, that have been in service for years on ethanol pump gas and no issues to date.

Sounds more like to me he just got a faulty pump from the get go since it didn't work right off the bat and didn't have all that much run time on it. Don't think ethanol is that quick to react.

You have posted that comment several times.

My two failed pump vehicles drove for years and years with 10% Ethanol.
No issues. When Michigan went to 15% ethanol is when the original OEM
255 L/hr fuel pumps quickly failed. In Michigan that 15% might actually
be over 20% depending on the supplier.

I am saying the amount of ethanol percentage is what killed them over time.
What is the average Fuel Ethanol percentage at your location?

Tom V.

[Formulajones]

Yeah the subject keeps coming up, so I post my results Felt that needed to be said again so the thread wasn't clouded, since ethanol didn't have anything to do with Scotts issue.

Our ethanol is advertised at 10% however that varies from pump to pump. I've checked a couple of them in the past with those cheap little test kits on ebay and found some pumps were as high as 17%.

But that wasn't done for worry of pump failure, I was checking into that for tuning purposes.

[Scott65]

When I get my content sensor going, I will check the content of ours here and post it. I dont believe it's relevant to my failure though. Soon I will have mine ethanol "proofed" pardon the pun. At least I hope it will be. The pump is claimed to be, ptfe lined hose should be, and a brand new tank should be...

[Scott65]

I guess I'll need to call Magnafuel and verify my 10 micron post pump filter element is good for E85 too... THEN I will be ok hopefully.

[HWYSTR455]

Probably just a bad pump out of the box. I happens.

Refresh my memory, you are running a bypass regulator?


.

[Scott65]

Yes, Magnafuel Vac/boost referenced.

[Scott65]

Things are looking good so far, logs show good fuel pressure in all conditions. Less than half a tank doesn't show any dips on hard launch. The cold weather and more load had me adding fuel to the table, but pressure was holding in all encountered scenarios so far. Line replacement and content sensor installation will hopefully get completed next weekend.

[Formulajones]

[Scott65]

Finished the line replacement yesterday, and wired the content sensor today. Pic of gauges included. Looks like ~6.7% around here. I'll check it periodically and as the seasons change, but doesn't matter that much with the ecu compensating for change automatically (now that I have the sensor and am able to enable that function.

[Scott65]

So, evidently, along with new instrumentation comes new potential concerns... We went for a drive of about 30 minutes today. Upon return, the fuel temp was 115f. I have a fuel cooler on the return side on the frame under the car. Guess we shall see what summer shows... Fuel level was a little over half.