Did you try smacking it with the end of the Dewalt impact battery?
Being serious, that sucks.
Being serious, that sucks.
CK5
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I bonked it with a dead blow a few times.
RMA submitted, I also discovered that Summit had the next size down pump (plenty for this engine in the shop truck) on the shelf. It will be here Friday.
I did a little work on the truck while waiting for parts. I cleaned up the fuel line routing a bit with some additional clamps that hold the supply and return together. I also ran the PWM wire for the fuel pump although I still need to get it pinned in to the ECU. The last thing I finished up was making a flange for the removable panel and I got that drilled, tapped and countersunk the bolts into the panel. It came out pretty clean, shouldn't be very noticeable once it gets dirty again.
The new fuel pump showed up late Friday, Amber and I finished up a few other things and got the new pump installed. Yesterday was the test drive for the fuel system, everything seemed to work good except my new fuel pressure regulator bleeds off almost instantly when the fuel pump shuts off. This makes startups slow as it has to build pressure in the 1/2" fuel line. I'm going to ask Motion if that's expected or of there's something wrong with it. I have a check valve installed between the filter and the regulator so it shouldn't be bleeding back through the pump.
It's a little louder than I was hoping for, but when it's at the lowest speed (idle) you can't hear it over the exhaust unless you get real close. It's also not audible in the cab at all, so that's nice.
It's a little louder than I was hoping for, but when it's at the lowest speed (idle) you can't hear it over the exhaust unless you get real close. It's also not audible in the cab at all, so that's nice.
Check valve should be as close to pump as possible. If not in the pump
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Fuelab just stated it needed to be between the pump and the regulator, but I don't think that's the problem. I can watch my fuel pressure gauge drop from 55psi to 2 in about 2 seconds once the pump shuts off.
No return line ?
Only other explanations, injectors leaking down, or check valve is NFG
There is a 1/2" line running from the pump to the filter, through the check valve and into the regulator. From the top side of the regulator there is a 6AN line going to my fuel rail (this will get changed with the new engine) and a 4AN fitting going to the nitrous fuel solenoid. From the bottom of the regulator there is another 1/2" line that goes back to the tank.
I don't think that's the issue, I don't think the fuel pump would leak back fuel that quickly even without a check valve. I'm pretty sure it's the regulator.
Only if the regulator has a return. Which a PWM doesn't need.
It does have a return as I stated before, and yes even a PWM pump needs a return. It can't stop the pump, it only regulates it between 50 and 100% speed I believe.
Hmm, factory pwm systems don't use a return line. Another check vslve won't work, only possible band aid I can think of off hand is smaller return line or a restricting orifice.
Maybe a normally closed solenoid valve,that opens with key hot power,in the return line.
Maybe a normally closed solenoid valve,that opens with key hot power,in the return line.
More modern port fuel injection (not Direct injection) use a returnless fuel system for simplicity and weight savings. The regulator is built into the pump assembly in the tank.
Currently I am running an LQ9 intake and injectors so they are set up to be returnless. Here is how I have everything hooked up.
On the pump side Fuelab integrated 3 ports for returns/vents/etc. I labeled the return and pump discharge.
On the regulator side there are 3 sections of the regulator. High pressure which is where the fuel supply comes in, I also have the fuel rail and nitrous fuel solenoid hooked up to this section. Low pressure, this is the return to the tank. Vacuum/boost reference, this is hooked up to the intake manifold.
The Fuelab pump is a brushless pump that can be speed controlled with a PWM input from the ECU. It takes a square wave A/C signal that goes from +5V to 0V between 500 and 5000hz. Grounding this signal wire makes the pump run at 50% speed so I am assuming that is the slowest speed it can run. Disconnecting the signal wire makes the pump default to 100%. I have a MAP vs RPM graph that controls the speed of the pump based on MAP and engine speed.
I did not have the leakdown problem before I switched to this setup. Previously I had a Walbro 255lph external pump going through a Corvette fuel filter/regulator and it would maintain at least some pressure for days after it last ran.
Currently I am running an LQ9 intake and injectors so they are set up to be returnless. Here is how I have everything hooked up.
On the pump side Fuelab integrated 3 ports for returns/vents/etc. I labeled the return and pump discharge.
On the regulator side there are 3 sections of the regulator. High pressure which is where the fuel supply comes in, I also have the fuel rail and nitrous fuel solenoid hooked up to this section. Low pressure, this is the return to the tank. Vacuum/boost reference, this is hooked up to the intake manifold.
The Fuelab pump is a brushless pump that can be speed controlled with a PWM input from the ECU. It takes a square wave A/C signal that goes from +5V to 0V between 500 and 5000hz. Grounding this signal wire makes the pump run at 50% speed so I am assuming that is the slowest speed it can run. Disconnecting the signal wire makes the pump default to 100%. I have a MAP vs RPM graph that controls the speed of the pump based on MAP and engine speed.
I did not have the leakdown problem before I switched to this setup. Previously I had a Walbro 255lph external pump going through a Corvette fuel filter/regulator and it would maintain at least some pressure for days after it last ran.
The truck didn't stay together long. There's a Friday night drag event on the 28th and I want to take the truck one more time with the old engine and new transmission to make sure everything is good to go before putting the new engine in.
Out with the old and in with the new!
Also, the TCI 700R4 is for sale, it's exceeded my expectations and has been flawless the entire time I've owned it.
Out with the old and in with the new!
Also, the TCI 700R4 is for sale, it's exceeded my expectations and has been flawless the entire time I've owned it.
The transmission is installed! There's still a lot of work to do, but it's bolted to the engine, we reconfigured/moved the crossmember and have it all mounted up. I bought the kit to hook my Winters shifter up so that's good and surprisingly the driveshaft looks like it will still work once we swapped out the yoke!
Unfortunately, the dipstick tube I bought won't work with the Reid case so I need to order a different one. I'm going to drop the pan so I can install the temp probe that I pulled out of the 700R4, then there's all the wiring and ECU programming. It should be driving again by next weekend though!
Unfortunately, the dipstick tube I bought won't work with the Reid case so I need to order a different one. I'm going to drop the pan so I can install the temp probe that I pulled out of the 700R4, then there's all the wiring and ECU programming. It should be driving again by next weekend though!
There's only 3 places the fuel pressure can go right? Out an injector (which would flood the engine) out the regulator end or out the pump end/with the check valve. Any way you can block off various points such as before the regulator or after the fuel pump with a manual valve? May narrow down where that's going.
I had already sent a message to Motion asking if this was expected behaviour. This was their reply: "Any return style of fuel system will bleed off the pressure after priming, so this is completely normal, and the only way around this would be if the pump was an in-tank setup with a check valve to hold pressure."
Now, I don't agree with their reply, but I'm also not going to argue with them about it. I'll just program my fuel pump so it runs for 10 seconds on key on, then I can just wait a few seconds before I crank the starter.
Now, I don't agree with their reply, but I'm also not going to argue with them about it. I'll just program my fuel pump so it runs for 10 seconds on key on, then I can just wait a few seconds before I crank the starter.
I've got a holley regulator and in tank pump with a return setup and mine drops pressure once you turn the key off. I just wait for the holley terminator screen to boot up and by then it's primed and I start the truck.
