Technical Virgin fuel system - no fuel coming through line

Just finished putting together the fuel lines on my 57, and I went to try running it with gas from the tank for the first time. I emptied an army surplus jerry can’s worth of fuel into the tank, so just under 5 gallons, but I cannot get fuel to pull from the tank.

So far, I have checked that the (new) fuel pump has vacuum while cranking, blew air from the rubber hose at the tank to the front of the car with a helper feeling for air coming through the line. I also blew air from the sending unit into the tank, and my helper said they could feel air coming out of the gas cap hole as well.

So by that, I’m pretty certain there are no clogs. The car will run off the float bowls for about 30 seconds, but then just dies because it doesn’t pull fuel from the tank.

What do I try next? Is there a good way to check for air leaks? I’m not sure what else it could be. Everything is brand new so dry rotted hoses and rust in the hardlines isn’t really an issue here. And like I said, the pump is pulling good vacuum. My gauge said about 5-8 lbs from the inlet.

 

Try the "sock" on the fuel pickup/sender
57's are easy to pull the sender with the tank still in place [except those awful clutch head screws]

 

I’d try going from the fuel pump to a remote tank.
Eliminate your tank and lines.

 

Did you blow into the filler neck with a rag around the blow gun to push gas though the line?

Did you check the pickup tube on the sending unit to make sure that it didn't have a hole or wasn't damaged. Blowing back to the tank though the hose or though the tube on the sender usually will blow the sock off the end of the tube if it is plugged up.

 

When you blow back through the sender into the tank, did you hear bubbles? If not, the tube on the sender may be too short and not down in the fuel. Some of the new senders you get today are not correct or don't work, right out of the box.

 

FWIW - I had a brand new out of the box plastic inline fuel filter I replaced on my ‘37. Went to crank, no fuel. Somehow during the manufacturing process, the hole in the body of the filter never got made; you’d never see it by looking at it. Never crossed my mind - now I check them prior to install.

 

I'd be wondering if the end of the fuel pickup in the tank is reaching into the gas that is in the tank.

 

Did you tighten this connection firmly? Any micro air leaks will cause loss of suction.

 

Thank you for the ideas guys, I have a few more things to try now. I think the issue has to be the sending unit or an air leak. I’ll pull the sender out and have a look at it. I actually have an extra one on the shelf so it wouldn’t hurt to compare them.

 

Take a steel ruler and stick it in the tank through the sender hole. Then compare it to the sender and see how far the fuel pickup is off the bottom of the tank. Should be around 1/4" to 1/2".

 

It turns out I was right about it being an air leak or the sending unit. It turns out that the sending unit had some cracked solder around the tube where it mounts to the bracket, which I don’t think had anything to do with it, but I decided to swap in the other sending unit I had and also eliminated the small length of rubber hose I had between the hard line and the sending unit. Now it’s hard line to hard line.

After I had that all put back together, I decided to give it some air down the filler neck again and low and behold, I heard fuel spilling onto the garage floor up at the fuel pump! The happiest I’ll ever be spilling gas!

It starts and runs off the tank now, so now I just have to sort out the leak I have up by the carb.

 

paging @Pist-n-Broke , please pick up the white courtesy phone.

 

Sounds like you may have cured your problem. I just had a series of small issues that put my 51 on the roll back. It seemed like I was going to have another fuel pump issue, not so. I had recently fought a battle with a Customers fuel system. SBC and 3 pumps from NAPA that all were running extreme high pressure and sinking the float. The cure was an Edelbrock high performance, part # 1721 and proudly on the box in Red White and Blue "made in the USA" and his issues went away and still are.
Several weeks ago I had time to do some spring maintenance on my 51 and with now 85K trouble free miles often I do a few little things that aren't par for service work. Yep, little plastic guy with 3/8" ******s. I like seeing what they are picking up when I throw them away with each oil change. This time I changed the Rubber hose on both sides and had planned that last time after noticing they were not as flexible as I like. This car only gets fed non E fuel so so rubber things tend to last longer it seems. So, I'm halfway through my 3 full tank of fuel since my service work and at 80 MPH she starts acting up. I slowed up some and it smothed out. Well okay, something to look into. I got off the freeway and was in normal traffic and it's just not real happy but running along. I stop at a red light and it dies but starts right back up and off we go. I'm thinking I must have got a little water in my last tank of fuel. I'm not far from my normal station so I decide to top it off and maybe mix the water up a little more so I can get home. I'm now full and it starts fine and I head for the Hwy and it shudders and Dies. W.T.F? I know I'm not far from B-B"s driveway so an urgent phone call and head for a safe spot and some tools. I wasn't sure I'd make it but luck was on my side. It wasn't flooding, it was starving. B-B is leaning over my fender and says hay, look at that filter it's not getting any fuel. Motor idling and the incoming fuel was about the size of pencil lead. With the mileage on the total package, I wasn't surprised the pump had given up. I finally get my car on my stretcher (that was an event of it's own) and pick up a new fuel pump for it. No Big Deal. That is until the new pump didn't cure the problem. Well it kinda did, I drove it about 20 miles and the issue reoccurred. Now I am going full FBI on this extremely reliable hand-built toy. I opened the carb and both needle and seats have really fine debris in them, but both fuel bowls aren't close to being full. I rolled the plastic filter that wasn't full to look at what was on the bottom.

 

Stupid touch pad sent without authorization!
So after inspecting the inside of the tank for debris and there wasn't any, I pulled the filter. Low and behold the problem. The New rubber hose was shedding rubber and the new Filter with 3/8" ******s on both ends has a feed opening of .092 and has junk from the hose backed up against it stopping even that much fuel getting into the filter. element. Ya, I was real pleasant to be around for a few days. I have a new plan and waiting on the new filter unit to arrive.

 

I actually texted B-B a photo of the inlet hole but can't seem to get it to attach.

 

I will, and do, use rubber fuel hose. ONLY high quality, high pressure fuel injection hose. With those ugly worm drive clamps. No problems so far.

Ben

 

Here’s your pics buddy. Watch those cheap *** filters.

 

Can you believe Fram stopped making there in line canister changeable cartridge style filter unit? WTF?