I am looking for some suggestions on a problem with my fuel supply. My inspection bowl under the primary fuel pump had lots of water in it today. I drained it off then tried to purge the air out of the system by opening the bleeder valve and turning on the key on. Fuel filled the bowl quickly but the fuel pump kept going crazy and wouldn't slow down. I kept working on it but couldn't get things to work. I tried to run the engine but it died shortly after starting as if not getting any fuel. I pulled the "out" hose from the pump and there was nothing coming out. The fliter was changed recently but I have been seperating a fair bit of water this season (another story regarding the fill cap). So I am trying to figure out if the pump is dead. It still clicks loudly as usual bit much faster......does this mean it's ok or could it be done? Is it being starved for fuel by a plugged filter of something else? Could there be some sort of airlock in the pump and it can't prime itself? I have tried to research the board quickly but I am on the run time wise and I was hoping that with all the wisdom on the board I could get some trouble shooting thoughts and ideas. The fuel gauge reads just under a half and I read with interest that it should be able to run without a pump. I plan on going out to the boat tomorrow to get it ready for a 4 day weekend with my family so time is an issue...
Thanks for any thoughts!
I have pulled the screen in the past, the fuel looks clear (no growth), I was hoping to get through this next 2 weekends then I don't mind pulling the tank etc. etc.
With the pump ticking that way, it sounds (from here!) like a bleeding problem. If the filter underneath the pump is clear and you don't have fuel flow then fuel isn't getting to the engine. Hard to tell if the pump has died, it could be based on your description, but have you removed the hose TO the pump to see if fuel is flowing? Is the valve to the tank open (happened to me!)? Only answers I can think of so far given your symptoms.
I didn't have a lot of time. I didn't check the fuel to the pump yet but I will now that I read that it should siphon on it's own. I'm also getting more suspicious about the filter although it should be good for another 50 hours???
Unless I have a better idea I might have to do the whole enchilada...pull the tank, check all the hoses, polish the fuel and change the filter, blah, blah, blah.
I just didn't want to have to do that yet. A few more weekends and our season will come to an end so I would have lots of time for all this..........
A short easy solution would be great for just now!
I agree with Stu. It is likely that you have air in your system that needs to be bled. Try opening and closing (for a few minutes) the "knurled knob" near the injectors (see many posts on this site) while the pump is on. You may be able to bleed all the air out in this way. I doubt that your pump is dysfunctional but it is possible. The rattle you describe is consistent with air in the system. If you fill your tank up, fuel should gravity feed anyway -hence if you get the air out of the system your engine will run even if the pump is bad.
Good luck,
Ken
I did have the "knurled knob" open. In fact I have been running with it cracked open all season to help polish and seperate water from the fuel. It just keeps ticking very quickly.
Jeff,
Is the priming knob on the top of the Racor screwed tight? That could cause loss of prime. Also, the gravity flow doesn't work for me; when my pump ground wire got loose and the pump stopped, so did the engine. So I wouldn't assume that's gospel.
Are you sure you have enough fuel in the tank? Many of us have eventually had problems with the sender. It may read 1/2 full but it could be much different.
Sorry for the basic question, but is the fuel shut off at the tank open?
And yes, the pump could be gone. Test it too before pulling the tank.
Ed
The priming knob has always been seized. I've never been able to move it. I have replaced the sender a couplpe times, but nit for 5 or 6 years, so maybe a problem but there should be lots of fuel. I will find out when I pull the tank I guess. I have never closed the fuel shut off so I am sure that it is open. How do I check the pump....it clicks like crazy. I am thinking that it is being starved of fuel. Clogged filter? Pick up tube problem? I don't know yet.
Try checking the pump by disconnecting the "in" hose and replacing with a section of hose leading from a container of diesel (glass bottle, jerry can, etc). Disconnect the "out" hose and replace with a short section of hose leading into an empty container. Also check the filter that is in the pump. If your fuel line goes into the Racor first, as it should, that filter should be clean, but you never know. Give it a check.
Key the ignition to "on", but not "start" and see if it flows. Be sure to turn off the fuel valve at the tank first.
If it flows, your problem is airlock. If it doesn't, the pump is gone.
Good luck,
Ed
Good idea. I'll start with that!
Another thought, since you've had water in your fuel, that is the perfect breeding ground for algae growth in the tank, so your filter could be clogged from that.
I would see if you get a gravity flow of fuel directly off the tank from the first hose connection, whether it be at the filter or the pump. If you get a flow, then you know it's something down stream(the filter of the pump). If you don't get a flow, then your tank is low on fuel or there is a clog somewhere. Some folks have "temporarily" cleared these clogs by blowing air back towards the tank.
Make pulling the tank your last option.
Mike
Mike beat me to it. Use your dingy pump to ensure the line between the Racor and your tank is not plugged. You should be able to hear the air bubbling as you back blow. If you have been treating with extra biocide because of the water leak, it could also be a filter restriction.
Jeff : You mentioned "I've pulled the screen in the past..." Are you talking about the screen on the fuel pump or the screen on the fuel pickup tube? Yours sounds like a classic clogged screen on the pickup tube screen - which should be removed !!
To check fuel output remove the fuel hose (to the engine) from the fuel pump output and attach a length of 3/8" fuel hose. Turn ON the key switch (activating the lift pump) and see if fuel comes out.
If not remove the hose from the fuel tank to the Racor and see if you can syphon any fuel from that line? Fuel lines do not normally clog, but the can get a kink.
A few thoughts
Thanks for all your thoughts guys.
I went to the boat at noon today and spent the afternoon proving Murphy Law true a few times.
The first thing I did was to disconnect the fuel line and blow into it. Yes I heard bubbles. Not empty so fuel gauge ok. Then I managed to get the line out and low enough that I could suck on the hose and draw enough fuel that it began to siphon into a clean bucket and watched for crud. Pick up not clogged and hose not kinked. Then I hooked up a couple of hoses to the fuel pump and put one into the new fuel I just drained off and the other into a different bucket. Then I turned on the power and watched the fuel pump move fuel from one bucket to the other. Fuel pump works. Then I used the fuel pump to empty the tank into two new large pails. I had planned on polishing the fuel with the old filter then using it again after pulling the tank and sloshing it about with a gallon of acetone but the diesel was all murky and just didn't look good, so I dumped it. Bad fuel. Unfortunately the marina fuel station closed 5 minutes before I got there so I couldn't get fuel today. So I continued with the clean up and reinstalled the tank. I also pulled the fill fitting to replace with a new stainless fitting but it was too small in that the new screws would have caught the edge of the center hole for the old fitting. So I picked up another fitting on the way home, will get some diesel at a gas station and continue tomorrow after work. I will change out both fuel filters, install the new fitting, hook up the fill hose, add fuel and additives and hope that I will be good to go for a Wednesday night departure. I am thinking that the problem was a clogged filter. Even though it was only about 20 hours old and I had used lots of biocide it seems that it was starving the pump. Wish me luck! I won't post again unless things don't work out as they should.
While you're doing all this, you may want to concider replacing the fuel line hoses.
Good luck. Looks like you're making progress.
Mike
Word of Caution !!! You can overdose using too much Biobore JR.(that's powerful stuff) I believe that is what crazed the smooth machined parts in my old injection pump!! A thought
I have finished changing out the VCG and the timing belt along with the tensioner. Everything was working great then my feul pump seemed to go bad. I am not gettting any fuel to the engine and so I am trying to check the relay but I can not find it. Does anyone know were it is located. Thanks
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review this heating install (http://www.www-heatingrepair.com/)
M25XP? There is no relay. The pump goes on when the ignition switch is turned on.
Check the wiring, I've found the ground wire at a butt connector disconnected on one boat I worked on, underneath the head sink on the way to the fuel tank.
Franky : If you look at the (-) ground wire, I also installed another gnd wire to the screw down brack for a double gnd by joining them together. A thought