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Want a Aftermarket EFI regulator that holds pressure with key off
My aeromotive 13301 doesn't hold pressure after the prime is over or the key is off. It immediately goes to zero in less than 1 sec. I run a -6 feed from my Holley twin dominator 1400hp pump and then a -10 on the return.
I don't think it's helping my cold start issue and I've tried to remedy the situation by modifying the regulator to seal the ball
Better and even add another regulator on the return line. I pinch off the return line and the pressure holds. So it's the design of the regulator which sucks.
OP, i have the same problem with my Magnafuel regulator. Ive been wanting to try a check valve like toytech says but havent purchased one yet.
Check valve would work if you were losing pressure in the feed line. You need to verify where the pressure/fluid is relieving itself. Pinch pressure line and see what happens, then do the return. I pinched my pressure line and nothing but no fuel getting to regulator. I pinched my return and pressure
Stayed but skyrocketed. The way a check valve works is that it flows in the direction of the fluid and stops reverse flow. So putting a check valve in the return would do nothing since u need it to flow and they have a very small cracking pressure. Putting one in the pressure line would help if that's where your loosing pressure but most pumps when not
Operating have an internal check valve or won't let pressure bleed off through the pump.
Check valve won't work in my application unless it has a 40-60psi cracking pressure.
Im running the Aeromotive 13129 & after prime it drops to 40 & stays. Starts right up & goes to set psi once running. Question, why are you running a -10 for your return & a -6 for feed?
Im running the Aeromotive 13129 & after prime it drops to 40 & stays. Starts right up & goes to set psi once running. Question, why are you running a -10 for your return & a -6 for feed?
How long does it hold the pressure for?
$128 to replace my regulator if it holds pressure might be worth it. I would need to know for sure that the regulator holds pressure with the pump off.
I used to run a 521 BBF with a carb setup, stock tank, sumped, high volume aeromotive pump and ran -10 feed and return lines due to the pump volume and be able to regulate pressure. I then switched to a FAST 2.0 EFI and changed the pump out for a A1000 (returned that POS) and went with the HOlley dominator setup, changed feed line to more EFI friendly -6AN, swapped regulator springs and all is well. Now Ive sold the 521 and going 5.3 with supercharger to get more driveability out of it. Ive left the fuel system as is for this setup.
-10AN return is because the line was already run and it doesn't matter the size since its not under pressure and all it does is return fuel back to the tank so I'm not worried about its sizing as long as its adequate.
$128 to replace my regulator if it holds pressure might be worth it. I would need to know for sure that the regulator holds pressure with the pump off.
I used to run a 521 BBF with a carb setup, stock tank, sumped, high volume aeromotive pump and ran -10 feed and return lines due to the pump volume and be able to regulate pressure. I then switched to a FAST 2.0 EFI and changed the pump out for a A1000 (returned that POS) and went with the HOlley dominator setup, changed feed line to more EFI friendly -6AN, swapped regulator springs and all is well. Now Ive sold the 521 and going 5.3 with supercharger to get more driveability out of it. Ive left the fuel system as is for this setup.
-10AN return is because the line was already run and it doesn't matter the size since its not under pressure and all it does is return fuel back to the tank so I'm not worried about its sizing as long as its adequate.
Ok gotcha, that makes sense. I really couldn't tell you how long it holds pressure after priming as Ive never really paid attention. Ive left the key in the on position without starting a couple times for a minute or two before starting & it never drops below 40. Car always starts right up in warm or cold weather & that's running E85, which hates cold weather.
Yup, I did that 2 days ago and no luck. I even added another cheap Holley carb regulator on the return line to see if I could get it to hold pressure and nothing.
Only good news is I threw a ton of cranking fuel and prime fuel at the tune and the motor started first crank. Ran rough for 10s of so then it got a huge burst of fuel or timing and smoothed right out. I verified I have 58psi prime and goes to 0 immediately with the pump off, then verified it has 58ish while cranking.
I'm tempted to get a new regulator but it has to work to spend the money. Only bc my regulator is fine, just doesn't hold pressure with the pump off. Otherwise we're looking at $150 or so for a different aeromotive regulator. Or I could get a cheap Chinese one and just see how it works.
If it is still not holding pressure when off, then you need to try to re-seat the ball again. This is the only thing that would let the pressure leak back down the return.
The only other thing would be if it is leaking back past the pump
If it is still not holding pressure when off, then you need to try to re-seat the ball again. This is the only thing that would let the pressure leak back down the return.
The only other thing would be if it is leaking back past the pump
Ive modified the seat to have a larger contact patch with the ball already, had it apart 2 times and reseated the ball twice with no luck. I have also verified in the past posts that fuel pressure will hold if the return line is clamped... so no fuel pressure loss through the feed port through the pump.
Its the design of the regulator... since its both carb/efi the return port in the the regulator (also ball DIA) is HUGE! I though say the hole is easily 5/16" in DIA (assuming for the carb low pressure high volume). The hole was also a sharp edge (not beveled) and it wore into the ball alittle. I beveled the edge and used very fine sandpaper to smooth it all out including the ball. The Ball seats much better now that it fits into a "cup" but still no dice in holding pressure.
This regulator does not look like other EFI regulators (on the inside) like other EFI regulators do. No long tower where the ball port is located where its not located directly in the incoming fuel path. Ive noticed that EFI regulators locate the Ball/return port opening in a tall tower high above the inlet ports (prob has something do do with the force of high pressure fuel pushing against the ball/diaphram) where this carb/EFI style regulator the ball is on the floor of the regulator (no tower) and its right in the bath of incoming flow.
Maybe try some lapping compound and lap the ball to the seat. If there is wear on the ball then it will have to match the seat to seal, just making a bevel is not enough.
Dont have any and not getting any. I used 400 grit on the ball to contour the seat that the ball fits into... its not getting any better than that. Tired of messing with this thing and no way for sure that the added time and cost would even fix the issue.
I personally dont think carb and EFI can share a simular design which is prob whats causing the issue. Id rather get something specifically designed for the application. The regulator works great as a bypass and technically works for either application I might just leave it and deal with the longer cranking. The only way i would change it out would be to find another one that holds pressure for sure.
Also looking at your regulator... you have a different design than mine... yours looks more like the EFI design that I see specific to EFI applications.
A cheap/quick fix is to install a fuel pump momentary prime button. To prime just before/during cranking. A button and some wire to your FP relay and done!
A cheap/quick fix is to install a fuel pump momentary prime button. To prime just before/during cranking. A button and some wire to your FP relay and done!
I wired my setup with a custom relay setup so I can turn it on anyway that I want. My relay is located by the fuel pump but I run trigger wire on the firewall in the engine bay. Basically I use spade connectors which allows me to switch from ECM control to Switched 12v in about 5s flat. This is how I've been testing the fuel system and trying to figure out the long crank issue.
The ECM can control the prime if I feel like it (will prime for 3sec) and then pressure drops or I can connect to switched 12v which turns the pump on all the time when the key is turned to run. So I can run the pump continually if I want. Obviously having the ECM control the pump is safer but running the pump off the switched 12v is nice bc I have full pressure/flow all the time. Annoying if I just want to turn the key on but not run the engine. Running a prime button would be ok if i wanted to complicate my cold starts but since pressure drops so quickly it would have to be priming during cranking. I also need 2 hands to start the car as I run a custom security system which requires both hands for the motor to crank over.
So I can crank within the 3s of PCM prime time, run the pump off switched 12v, or get a regulator that holds pressure.
A cheap/quick fix is to install a fuel pump momentary prime button. To prime just before/during cranking. A button and some wire to your FP relay and done!
As soon as you key on, the pump primes anyway.
It amazes me why so many people think pressure dropping after shutdown is a problem. It isnt.
05-04-2016, 11:08 PM
Want a Aftermarket EFI regulator that holds pressure with key off 
