525 fuel issues
06-21-2012, 01:01 PM
#11
Registered
Thread Starter
Join Date: Mar 2005
Location: North Texas
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Resolved
Well after a couple of weeks of traveling for work, I had time last weekend to try to solve the fuel pressure problem on the boat.
I changed the fuel water separator and the fuel filter up by the intake manifold. I wish there was a way to clear the fuel system out before unhooking the lines instead of using rags/towels to try to catch the fuel when you open the lines. I really hate fuel in the bilge! I put fresh fuel in the port tank (I was running off of the starboard tank previously). Fuel pressure was fine at idle but when I took it out for a run, the same issue with the bouncy gauge reappeared.
I previously bought a cheap fuel pressure gauge kit from Harbor Freight and decided that I should check the pressure at the intake before hauling the beast to the dealer. Eliminator had the fuel pressure gauge running off of the original schrader valve fitting on the intake so I unhooked that stainless line and put my cheap Harbor Freight gauge on it. Fired it up and fuel pressure was steady at idle. Took the boat out and ran it and had good fuel pressure and while the gauge was not rock solid as the Autometer on the dash used to be, it only fluctuate by 1 or 2 PSI and I can attribute that to either a cheap gauge or the fact that it was zip tied to the throttle bracket and was probably just engine vibrations. Regardless this tells me that the fuel system is good and my dash gauge is bad.
I was going to hook up the Harbor Freight gauge at the dash so I reconnected the line at the intake manifold and unhooked the line at the back of the gauge. WOW, smelled like bad gas at the gauge - I have built enough old cars and bikes to know that smell! I unhooked the line at the manifold and blew out the line into a bottle - bad gas and a little gunk came out. So I figured I would clean up the fitting on the gauge with some carb cleaner and throw it back in the dash until I could order a new one. Low and behold after putting it back in after cleanup and hooking everything up, it worked as it should - rock steady and reading the correct pressure.
SO my conclusion is that the fuel in the stainless line that runs from the intake to the gauge doesn't drain completely and once fuel is in there, it doesn't recirculate either. After cleaning out the line and the gauge, everything worked so I guess when I winterize the boat, I will have to clear the fuel pressure gauge line as well.
At least it wasn't a fuel pump or regulator!!
I changed the fuel water separator and the fuel filter up by the intake manifold. I wish there was a way to clear the fuel system out before unhooking the lines instead of using rags/towels to try to catch the fuel when you open the lines. I really hate fuel in the bilge! I put fresh fuel in the port tank (I was running off of the starboard tank previously). Fuel pressure was fine at idle but when I took it out for a run, the same issue with the bouncy gauge reappeared.
I previously bought a cheap fuel pressure gauge kit from Harbor Freight and decided that I should check the pressure at the intake before hauling the beast to the dealer. Eliminator had the fuel pressure gauge running off of the original schrader valve fitting on the intake so I unhooked that stainless line and put my cheap Harbor Freight gauge on it. Fired it up and fuel pressure was steady at idle. Took the boat out and ran it and had good fuel pressure and while the gauge was not rock solid as the Autometer on the dash used to be, it only fluctuate by 1 or 2 PSI and I can attribute that to either a cheap gauge or the fact that it was zip tied to the throttle bracket and was probably just engine vibrations. Regardless this tells me that the fuel system is good and my dash gauge is bad.
I was going to hook up the Harbor Freight gauge at the dash so I reconnected the line at the intake manifold and unhooked the line at the back of the gauge. WOW, smelled like bad gas at the gauge - I have built enough old cars and bikes to know that smell! I unhooked the line at the manifold and blew out the line into a bottle - bad gas and a little gunk came out. So I figured I would clean up the fitting on the gauge with some carb cleaner and throw it back in the dash until I could order a new one. Low and behold after putting it back in after cleanup and hooking everything up, it worked as it should - rock steady and reading the correct pressure.
SO my conclusion is that the fuel in the stainless line that runs from the intake to the gauge doesn't drain completely and once fuel is in there, it doesn't recirculate either. After cleaning out the line and the gauge, everything worked so I guess when I winterize the boat, I will have to clear the fuel pressure gauge line as well.
At least it wasn't a fuel pump or regulator!!
06-21-2012, 02:02 PM
#12
Registered
Join Date: Jan 2004
Location: San Diego, California
Posts: 2,777
Likes: 0
Received 6 Likes
on
6 Posts
Nice troubleshooting work and and its nice to have an OSO'er come back on the thread and post the final fix and results. Thank you for the followup!
I personally don't like the idea of mechanical fuel pressure guages with lines of any type run all the way from the engine to the dash of a boat. I thinks it's just to much of a risk of a line failure or leak and the thought of fuel leaking in closed spaces and up by a helm with the chance of fumes and such igniting with spark in my mind is just to risky and dangerous.
I realize that electric fuel pressure guages are sometimes not as accurate or steady with remote sensors and such but they are a hell of a lot safer and one would not have to worry about fuel going bad or stale in the line and causing problems for the mechanical guage.
JMO
Best Regards,
Ray @ Raylar
I personally don't like the idea of mechanical fuel pressure guages with lines of any type run all the way from the engine to the dash of a boat. I thinks it's just to much of a risk of a line failure or leak and the thought of fuel leaking in closed spaces and up by a helm with the chance of fumes and such igniting with spark in my mind is just to risky and dangerous.
I realize that electric fuel pressure guages are sometimes not as accurate or steady with remote sensors and such but they are a hell of a lot safer and one would not have to worry about fuel going bad or stale in the line and causing problems for the mechanical guage.
JMO
Best Regards,
Ray @ Raylar
06-21-2012, 02:15 PM
#13
Registered
Thread Starter
Join Date: Mar 2005
Location: North Texas
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Nice troubleshooting work and and its nice to have an OSO'er come back on the thread and post the final fix and results. Thank you for the followup!
I personally don't like the idea of mechanical fuel pressure guages with lines of any type run all the way from the engine to the dash of a boat. I thinks it's just to much of a risk of a line failure or leak and the thought of fuel leaking in closed spaces and up by a helm with the chance of fumes and such igniting with spark in my mind is just to risky and dangerous.
I realize that electric fuel pressure guages are sometimes not as accurate or steady with remote sensors and such but they are a hell of a lot safer and one would not have to worry about fuel going bad or stale in the line and causing problems for the mechanical guage.
JMO
Best Regards,
Ray @ Raylar
I personally don't like the idea of mechanical fuel pressure guages with lines of any type run all the way from the engine to the dash of a boat. I thinks it's just to much of a risk of a line failure or leak and the thought of fuel leaking in closed spaces and up by a helm with the chance of fumes and such igniting with spark in my mind is just to risky and dangerous.
I realize that electric fuel pressure guages are sometimes not as accurate or steady with remote sensors and such but they are a hell of a lot safer and one would not have to worry about fuel going bad or stale in the line and causing problems for the mechanical guage.
JMO
Best Regards,
Ray @ Raylar
