68 RS Convertible

iTrader: (1)

So I'm on my way to pick up my 3 year old from pre school the other day in "daddy's loud car". Tops down, nice day for a cruise and all of the sudden car die's!!! WTF!!!! So I'm right around the corner from the school so I coast as far as I can, park it on the side of the road and hoof it the rest of the way to the school. No cell phone because I'm such a great shade tree mechanic my car won't break down
Use the phone at the school to call the wife and hoof it back to the car with the boy. Long story not so short I have her bring the 5 gallon gas can from home and I put the 3 or so gallons in that was in the gas can. Now after I put the gas from the can in I can hear the cheapo AC Delco in line electric fuel pump change tone, like its now picking up fuel. So I figure I ran out of go juice.
Drive to the nearest gas station to fill her up because I thought my fuel gauge was not working. I had just replaced the sending unit last fall because the gauge wasn't working. So I thought something was up with the new aftermarket sending unit. So I get to the gas station and less than a gallon later and I'm spilling $4.25 dollars worth of 93 octane all over the ground.
Limp her home and yesterday I drop the tank. I drained a guestimated 12 gallons out of the very full tank. Pull the sending unit, blow everything out with air and all looks well. No crap, schmeg or anything else unusual that is jumping out at me.
Little back ground. Fresh iron block 370 with a new to me, used Quick Fuel 850 that I just picked up. I have the fuel comming out of the tank to a filter, in line variety that you would use on any stock carb variety fuel system, nothing fancy, don't know how many microns it picks up. From there it goes to chepo AC Delco fuel pump up to Holley regulator, up to carb. Now I have one of those screw in fuel pressure gauges at the fuel log, up at the carb. Most times it only shows 2-3psi. I never had a fuel starvation problem so I thought the gauge was off. I had the regulator opened up to let as much pressure through as possible and still only 2-3 psi. Everything in the fuel system was new from when I did the swap in 2008. Probably only put 15-1800 miles on the car since the swap.
Any thoughts on what the problem was? I thought it was a pick up problem but I think I ruled that out once I pulled the sending unit.
Tomorrow I have a new Summit 140 gph, 18 psi (at least I think thats what it said) fuel pump with Summit inline filter (40 microns incase you were wondering). The sending unit I bought last year has a 5/16 return line that I intend to plumb in. I hope this will solve any fuel problems I had. I'm just looking for some thoughts on what anyone may have thought the original problem was.
Thanks for looking!

Greg

Pop N Wood

iTrader: (1)

Try cutting the old filters open and check the paper elements. Maybe something in there you aren't seeing. Might not hurt to do a check where you run without a filter and see what pressure you read.

Also be sure all the connections from the pump intake to the tank are sealing tight. A small air leak on the suction side will cause all sorts of issues. I'm sure you have already checked the plumbing for restrictive connectors or collapsed hoses.

Chances are your fuel pump was just not working well. You should have plenty of fuel with that summit pump.

68 RS Convertible

iTrader: (1)

I do plan on cutting the old filter to see what's in there. Nothing unusual about the lines or rest of the system. What threw me off was I could hear the pump change tone once the fuel got to it, but there was plenty of fuel in the tank. Guess maybe once I get the old pump and filter off and inspect them I may have more answers.

Thanks

S10xGN

iTrader: (11)

I had a nice looking Barry Grant 220HR pump that refused to pull fuel even though it was finally changed to a spot even with the 1/3 tank line. In frustration, I tossed it in the junk pile and installed a Holley black which never fails to pump! You can hear it "pull" in 2 or 3 seconds after a long sit with full system bleed-down.

68 RS Convertible

iTrader: (1)

Where do you have your pump mounted now? The summit pump I just got says to mount it in a such a way that it will be "gravity fed" from the tank. Where I'm looking to mount it is probably just below the level of the sending unit, if I'm lucky!!! Also do you have a return plumbed in? Just curious if not having the return line would affect the preformance of the pump. I am in the process of plumbing in the return from the regulator to the tank, but my prior system, that failed had no return. Just looking for some insight and wanted to see what other people were doing with their fuel systems.

Thanks !!

S10xGN

iTrader: (11)

Same place the BG pump was, still not "gravity fed", but I can't think of any street car that is (unless it's got a cell sitting on top of the trunk floor). You can see it behind the RR tire. I overbuilt my fuel system for "future upgrades" so it does have a return line and a good bypassing regulator...

Prorac1

iTrader: (4)

We have used holley blue and black pumps as "pullers" many, many times, even though your not suppose to. They work just fine. Eric L

68 RS Convertible

iTrader: (1)

So your mounting the pump up toward the engine? Yeah I know they don't recommend that. I'll keep it in mind in case I continue to have a problem.

Thanks

Prorac1

iTrader: (4)

No. We are mounting the pump back by the tank. But it is below the top of the tank, therefore making it a suction set up. The only way to get away from a true suction set up is to sump the tank or run a fuel cell. If I were you, I would install a pump inside the tank and use a mallory regulator to regulate it down to 6-8 psi. We did this on an S10 with a fuel injected intank pump and used the regulator that is made specifically for that. To regulate HIGH pressure FI pumps down to carb pressures. Or just install a sump in the tank.