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JohnK
08-31-2020, 11:26 PM
I'm wrapping up the braided AN fuel lines that connect my SS hard lines to the fuel filter, pump, and regulator. Ideally, I'd love to test the entire system before riveting in the trunk floor panels. My idea is to install the fuel pressure regulator and the braided line that will eventually connect to the engine, and cap the line. I'd then power up the fuel pump with a Power Probe. This will allow me to leak-check the supply and return lines, the function of the fuel pump, and also take a first pass at setting the pressure regulator. Does this sound like a reasonable idea?

FFinisher
09-01-2020, 07:35 AM
I'm wrapping up the braided AN fuel lines that connect my SS hard lines to the fuel filter, pump, and regulator. Ideally, I'd love to test the entire system before riveting in the trunk floor panels. My idea is to install the fuel pressure regulator and the braided line that will eventually connect to the engine, and cap the line. I'd then power up the fuel pump with a Power Probe. This will allow me to leak-check the supply and return lines, the function of the fuel pump, and also take a first pass at setting the pressure regulator. Does this sound like a reasonable idea?

Yep

phileas_fogg
09-01-2020, 08:13 AM
When you say "cap the line", do you mean dead-head the pump?

Instead, I'd mock up the fuel return as well, so that the flow would be pump to braided feed line to FPR to braided return line to tank. A couple or three gallons and you're ready to test.


John

P.S. You can test your braided lines using this https://www.amazon.com/gp/product/B009S5ICJY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1. Use a bicycle pump to pressurize the hose; then dunk it in a bucket of water & look for bubbles at the fittings. Don't be bashful about wiggling the hose at the fitting to make sure you've got a solid installation.

JohnK
09-01-2020, 09:04 AM
Sorry, I should have been more clear about my setup. I'm planning to run a gen 2 coyote. I have 3/8" stainless steel hard supply and return lines. The braided flex lines (Aeroquip PTFE -6 AN) connect the fuel pump hanger, filter and regulator to the stainless steel hard lines. What I would dead-head would be the braided line coming off the pressure regulator that would eventually run to the engine, so there would still be a supply-return loop (pump-filter-regulator-back to tank) that fuel could cycle through.

I've seen your link to the Fragola pressure test kit before - thank you for that! I purchased one based on your recommendation, and I've been testing each individual flex line after I assemble it. But it occurs to me that these are just one small piece of the puzzle, and testing this way still doesn't test the connections from flex lines to fuel pump hanger, filter, hard lines, etc. What I'm hoping to avoid is a small leak at the hanger, for example, that would require dropping the tank later to address but I could've easily dealt with now when the sheetmetal is not in yet.

egchewy79
09-01-2020, 11:54 AM
I found the factory block off plate and hole in the trunk aluminum wasn't large enough to reach the fittings on the pump hanger. I made my hole larger and made a larger block off panel to cover it using a scrap piece of aluminum (might have been what I cut out for my drop trunk kit). This allows me to actually tighten any fittings on the hanger with the trunk panel in place without needing to drop the tank.
I personally just tightened all fittings as tight as I could and didn't test for leaks until first start. I keyed the system to "run" which started the fuel pump, then checked all the fittings for moisture/leak prior to cranking the key.

Blue Viking
09-01-2020, 02:34 PM
I'm planning on the same shortly. Just gotta mount a fuel pressure gage to one of the rails, then I should be ready. Just going to hook a battery directly to the pump, haven't got the electrical installed yet. Wanna test while the plumbing is not crowded with wires for all the different sensors and wiring for the efi.

Brian76
09-03-2020, 09:44 PM
I left the trunk panels out for go carting to be able to check all brake and fuel connections periodically. You don't need to rivet them down yet

JohnK
09-03-2020, 11:12 PM
I do if I want to spray Lizard Skin in the cockpit and trunk.