V6-v8 fuel pump problems
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V6-v8 fuel pump problems
Hey guys, I finally got my car driving the other day after my 5.3 swap into the 2000 firebird. I origanaly used a walbro 255 in a modified v6 bucket, but kept blowing the feed line in the tank. I had heard the swap required an external regulator, but friends have proved only the main feed line from the v6 car needed to be hooked up to the ls1 fuel rail and all was good.
Idecided to ditch the ghetto walbro and bought a Delphi assembly made for the v8 car. It ran perfect for a few days. Then I tried starting the car, the pump grinded and then I heard a pop. Now it sounds fine when priming but has zero fuel pressure.
Is this a problem with not having a return line? The v8 unit has the internal regulator on it.
Idecided to ditch the ghetto walbro and bought a Delphi assembly made for the v8 car. It ran perfect for a few days. Then I tried starting the car, the pump grinded and then I heard a pop. Now it sounds fine when priming but has zero fuel pressure.
Is this a problem with not having a return line? The v8 unit has the internal regulator on it.
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Is new V8 pump for a LS based engine? If so, yes...it has an internal regulator AND you need to have a return line. The return line returns the fuel after the regulator....back into the fuel bucket. This fuel in the bucket....keeps the pump from sucking air when the fuel in the tank is low...and keeps pump cool(submersed in fuel). The first few days it worked properly...did you have a full tank of fuel?
I've run my OEM LS fuel bucket in my 78 tank all the way down below a quarter of tank with no issues...almost 1000 miles this year.
I've run my OEM LS fuel bucket in my 78 tank all the way down below a quarter of tank with no issues...almost 1000 miles this year.
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Originally I had a walbro 255, and I cut a hole in the bottom of the bucket for the filter, and a hole in the side so the bucket would fill. I kept blowing the feed line off this setup. So I bought a Delphi ls1 fuel pump assembly. It has the entire bucket unit.
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Just to add a little info, I started and ran this new v8 style pump with less than 1/4 tank while I was diagnosing transmission problems. When I actually drove the car I had a full tank. So it worked either way.
#9
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I'm using an OEM from a salvage yard...fuel pump bucket from a 2000 LS1 powered f body. I am not using the fuel float...I re-used my 1978 fbody one. To have piece of mind, I bought a new pump (GM replacement ..from a vendor on ebay) and replaced the one in the bucket. I did not cut/shorten/alter the bucket in anyway. I removed old pump, put in new one, connected the venturi line and the main line that goes to the fuel rail. I have a T (AN fitting)...with the excess fuel returning to the bucket. My understanding is the bucket has a series of check valves in the bottom. when the pump senses it's sucking air (from low fuel or sloshing due to cornering or acceleration), the valves close and it sucks fuel from the bucket. This fuel has already been filtered from the bottom of the bucket, so no need to re-filter it. the bucket is always seeing fuel from the return line.
read this thread..it may help.
http://www.nastyz28.com/forum/showth...=209472&page=5
i am using the vetteworks setup...good luck. I may be able to help more..but I am at work and do not have all my photobucket or web links.
This is a V8, LS1 F Body fuel bucket...the line closest to you is the return line (with the T).. the center one is the vent, and the one farthest away (largest diameter) is the one connected to the pump.
Leon
read this thread..it may help.
http://www.nastyz28.com/forum/showth...=209472&page=5
i am using the vetteworks setup...good luck. I may be able to help more..but I am at work and do not have all my photobucket or web links.
This is a V8, LS1 F Body fuel bucket...the line closest to you is the return line (with the T).. the center one is the vent, and the one farthest away (largest diameter) is the one connected to the pump.
Leon
Last edited by reedld; 07-24-2013 at 08:44 PM.
#11
Just for the record, I did the exact same swap, 5.3L into my Y87 2002 Firebird (3.8 blew up) and I just used the stock V6 fuel pump and a corvette fuel filter for the return line. I had no problems. Be aware that the V8 fuel pumps DO NOT have return lines so you'll have to delete it if you go that route, you also do not need the corvette fuel filter if you use the V8 fuel pumps because they're internally regulated (which is why V8 cars dont have return lines)
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Okay, I need a return line. I know that. But now I need the fastest and cheapest way to get it. I have v6 fuel rails. A v8 pump with internal regulator. I want to find v8 lines and be done. But time is running out. I have a 99 corvette filter/regulator. Would running two regulators be bad? Could I run the corvette filter and keep the v6 lines?