Ok on to the next problem. Plugs fouling looking like soot around the edges. Decided to start at checking fuel pressure.
Fuel pressure check showed it at 50psi. Looked like the original FPR so I replaced it with one of those adjustable units from LMR. This one reads 52psi and I’m not able to get any adjustment out of it. Can’t lower it at all. I replaced the fuel filter with a K&N unit about a month ago when I replaced the fuel pump. It has a walbro 255lb fuel pump and 24lb injectors.
Not sure where to go next? Bad injectors? Could the bigger fuel pump cause this?
UPDATE:
So I disconnected the return line at the fuel rail and dropped the tank and disconnected it at the pump. I inspected the fuel line closely from the engine to the tank and there is zero damage to the line. I blew 120psi of compressed air through the disconnected line and it blew through the no issues. Pulled the fuel pump and checked the return line and it was clear. I did end up pulling off the little rubber backflow duckbill cap/valve off the return line as it looked warped on the tip. I figured I could replace it later and test flow with it off. I reinstalled the pump, tank, and reconnected the lines. Hooked up my pressure gauge and it still reads 50psi. Zero adjustment with the regulator. So now I’m wondering could I have a clog at the injectors and testing it by dumping the fuel at the supply line disconnected was just the path of least resistance, thus allowing me to adjust the FPR.
One thing I will do first. Replace the shrader valve at the supply line test port. It looks old and kinda beat up. I also want to get another pressure gauge for a sanity check. Do this first before I go replacing injectors. Thoughts?
UPDATE 2:
I’m starting to wonder if I should step down to the walbro 190? The 255 is too much for my application?
UPDATE 3:
I’m stepping down to a walbro 190. Will report back.
UPDATE 4:
Well, installed the walbro 190 and cranked it up. Fuel presssure was at 30psi and I was able to adjust it to 40 without vacuum. So it does appear the 255 was overloading my return line. Maybe I got a really well built 255 that was pushing 99% efficiency and flowing every bit of its rated flow?
The Walbro 190 is on and I can now adjust fuel pressure. Thanks to everyone for their help!!
Fuel pressure check showed it at 50psi. Looked like the original FPR so I replaced it with one of those adjustable units from LMR. This one reads 52psi and I’m not able to get any adjustment out of it. Can’t lower it at all. I replaced the fuel filter with a K&N unit about a month ago when I replaced the fuel pump. It has a walbro 255lb fuel pump and 24lb injectors.
Not sure where to go next? Bad injectors? Could the bigger fuel pump cause this?
UPDATE:
So I disconnected the return line at the fuel rail and dropped the tank and disconnected it at the pump. I inspected the fuel line closely from the engine to the tank and there is zero damage to the line. I blew 120psi of compressed air through the disconnected line and it blew through the no issues. Pulled the fuel pump and checked the return line and it was clear. I did end up pulling off the little rubber backflow duckbill cap/valve off the return line as it looked warped on the tip. I figured I could replace it later and test flow with it off. I reinstalled the pump, tank, and reconnected the lines. Hooked up my pressure gauge and it still reads 50psi. Zero adjustment with the regulator. So now I’m wondering could I have a clog at the injectors and testing it by dumping the fuel at the supply line disconnected was just the path of least resistance, thus allowing me to adjust the FPR.
One thing I will do first. Replace the shrader valve at the supply line test port. It looks old and kinda beat up. I also want to get another pressure gauge for a sanity check. Do this first before I go replacing injectors. Thoughts?
UPDATE 2:
I’m starting to wonder if I should step down to the walbro 190? The 255 is too much for my application?
UPDATE 3:
I’m stepping down to a walbro 190. Will report back.
UPDATE 4:
Well, installed the walbro 190 and cranked it up. Fuel presssure was at 30psi and I was able to adjust it to 40 without vacuum. So it does appear the 255 was overloading my return line. Maybe I got a really well built 255 that was pushing 99% efficiency and flowing every bit of its rated flow?
The Walbro 190 is on and I can now adjust fuel pressure. Thanks to everyone for their help!!
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