Hello, kind of new to the board...I hope I get my terminology right.I ran my Onan gen 2 weeks ago, with zero trouble. Went to start it on Sunday, and it acted like it was going to start right up...seemed to run fine for about 1 beat, stopped. I tried starting it again, same result. After that, couldn't get it to do a thing. I can hear it trying, but never actually starts. So how can I tell where my problem is? I realize it can be any number of things...moisture in the lines, clogged fuel filter or pump, or I guess even a clog in the line.... The place I normally take can't get it in for a month, and I don't want to wait that long. And husband is not mechanically inclined in ANY way :) Not sure if it matters, generator is on the roof, fuel tank is in the rear tack. Thanks!
Posted 2012-02-15 12:33 PM (#141010 - in reply to #141005) Subject: RE: Generator Trouble
Regular
Posts: 66 Location: Western US
Okay...sounds good, but stupid question....how do I check them, and what am I looking for. I think I have two....I can see one in my rear tack, and I think there's another up in the Gen compartment.
Posted 2012-02-15 3:06 PM (#141016 - in reply to #141005) Subject: RE: Generator Trouble
Veteran
Posts: 155 Location: North Salem, IN
Do you have a switch to turn on power to the fuel pump or does it run automaticly when generator is switched on? Either way, you can disconnect the fuel line anywhere after the pump and switch it on and see if you have fuel. You would want to do this in a manner to allow the fuel coming from the pump to be captured. (put another hose on the line and capture in a drain pan or gas can) If your switch is in the living quarters, it would be a good idiea to have a friend help you since you can't be in 2 places at once. If the pump doesn't run, make sure the fuse is good and you have power to the pump. Also check to be sure it is grounded well. There should be a fuel filter in the line as well. You'll want check it aslo to be sure it isn't clogged up.
Posted 2012-02-15 11:29 PM (#141042 - in reply to #141005) Subject: RE: Generator Trouble
Regular
Posts: 66 Location: Western US
Okay....test results: Took off fuel filter, which is up by generator...no fuel comes through line when I prime or try to start. Then disconnected fuel line from fuel pump, which is just above the tank in the tack room; left all the wiring alone. Still no fuel when primed or started. So can the pump be clogged, and if so, is there a way to unclog it, without replacing it? The pump and filter were replaced almost two years ago, and the lines cleared out as well. Thanks for the hand-holding!
Posted 2012-02-16 12:27 AM (#141044 - in reply to #141005) Subject: RE: Generator Trouble
Veteran
Posts: 155 Location: North Salem, IN
I wouldn't know were the fuse is located but I would guess it would be near the switch. Can you check with a test light to see if you have power to the fuel pump? That would eliminate looking for the fuse. If no power, make sure you have power to the switch. If you do have power at the pump, make sure the ground wire is making good contact. If it is, then more than likely you have a bad fuel pump.
Posted 2012-02-16 10:31 AM (#141068 - in reply to #141044) Subject: RE: Generator Trouble
Regular
Posts: 66 Location: Western US
This may have gone beyond my skill level, but I'll give it a shot.....I'm assuming there is power to the switch, because the light on it blinks, if I prime it, I can hear a sound that I normally always hear when I prime it.So next step is to test the power to the pump itself. Can I test that with the little tool you can test your trailer plug with, or do I need a more powerful tester? There are two wires that come out of the top of the pump, one black, one white. These connect with some kind of little connector to the wires coming from the trailer. I would imagine I "unplug" those, and test them?Thanks...
Posted 2012-02-16 2:54 PM (#141091 - in reply to #141005) Subject: RE: Generator Trouble
Veteran
Posts: 155 Location: North Salem, IN
You can test it with a simple test light that looks like an ice pick with a light in the handle and wire with a ground clamp on the end of it. You don't need any fancy tools.
Posted 2012-02-16 3:57 PM (#141097 - in reply to #141005) Subject: RE: Generator Trouble
Expert
Posts: 2957 Location: North Carolina
Looking at your pic... I see the wire seems to be discolored. Is that true? And it looks like the inlet side of the pump was sealed with teflon tape. Improper use of teflon tape to seal threads might cause your pump to get clogged. Always leave the first full thread clear of tape. Otherwise, the mating thread will cut the tape loose to clog something.
Posted 2012-02-16 4:35 PM (#141099 - in reply to #141097) Subject: RE: Generator Trouble
Regular
Posts: 66 Location: Western US
There's a black and a white wire exiting the pump...I think the semi-clear connector that is connecting the white wire to the red wire is making it look discolored. But in looking at it closer to answer your question, there seems to be three different splices between the pump, and the wires that seem to be coming from the trailer. So I guess there could be a problem at any of those junctions as well. I'm in the process of trying to get the "butt-connectors" off so I can test the wires...but either I'm just not strong enough, or you need a special tool. Though about just cutting the wire, but I should probably disconnect the batteries if I'm going to do that, right?
It looks like both in, and out sides have the teflon tape....when you say leave the first full thread clear...is that the first thread that goes in (so now you can't see it), or do you mean the last thread, the one you'd see first if you started unscrewing it?
Also thinking that if there are three splices, maybe I should eliminate those when I put the new pump on, so that there is only one connection....
Posted 2012-02-16 10:34 PM (#141112 - in reply to #141005) Subject: RE: Generator Trouble
Regular
Posts: 66 Location: Western US
Was able to determine I'm definitely getting power to the fuel pump. Didn't get the right pump today so going back in the morning to try a different one. The one that is being replaced isn't made any more. Thanks so much for all the help so far, at least I've been able to troubleshoot things enough to get to this point! :)
Posted 2012-02-16 10:55 PM (#141113 - in reply to #141099) Subject: RE: Generator Trouble
Expert
Posts: 2957 Location: North Carolina
Originally written by AJS on 2012-02-16 1:35 PM
It looks like both in, and out sides have the teflon tape....when you say leave the first full thread clear...is that the first thread that goes in (so now you can't see it), or do you mean the last thread, the one you'd see first if you started unscrewing it?
The first thread of the male portion going into (so now you can't see it), the female portion should be clear of the tape. As the fittings are screwed together, any tape over the fitting end will be cut free to clog the pump internals. or anything else ! ! Always do this when using tape... no matter which direction of flow in the fitting. You don't want pieces of tape in any system.
Posted 2012-02-16 11:31 PM (#141115 - in reply to #141113) Subject: RE: Generator Trouble
Regular
Posts: 66 Location: Western US
Good info, thank you!....do I need to use it at all? I was going to, just because someone had already done it...is one of those cases where less is more?
Posted 2012-02-17 12:44 AM (#141116 - in reply to #141005) Subject: RE: Generator Trouble
Expert
Posts: 3853 Location: Vermont
Originally written by AJS on 2012-02-15 12:04 PM
Hello, kind of new to the board...I hope I get my terminology right.I ran my Onan gen 2 weeks ago, with zero trouble. Went to start it on Sunday, and it acted like it was going to start right up...seemed to run fine for about 1 beat, stopped. I tried starting it again, same result. After that, couldn't get it to do a thing. I can hear it trying, but never actually starts. So how can I tell where my problem is? I realize it can be any number of things...moisture in the lines, clogged fuel filter or pump, or I guess even a clog in the line.... The place I normally take can't get it in for a month, and I don't want to wait that long. And husband is not mechanically inclined in ANY way :) Not sure if it matters, generator is on the roof, fuel tank is in the rear tack. Thanks!
Which Onan generator do you have?
Which model carter fuel pump do you have?
Depending on which carter fuel pump...does your system have a pressure regulator involved?
What is the actual lift height that the pump is having to deal with?
Posted 2012-02-17 10:27 AM (#141130 - in reply to #141116) Subject: RE: Generator Trouble
Regular
Posts: 66 Location: Western US
I have the Onan MicroQuiet 4000. The fuel pump WAS a Carter P61145S. It's 90" from the floor (where the bottom of the tank rests) to the ceiling. The pump is positioned 34" up from the floor. Once the fuel gets to the roof, it makes a turn, and travels roughly 8' to the gen itself. I don't know of a pressure regulator on the system...
Posted 2012-02-17 10:40 AM (#141131 - in reply to #141005) Subject: RE: Generator Trouble
Regular
Posts: 56 Location: Shawnee, Oklahoma
This may not apply to you, but we have encountered a lot of generator problems with customers who use gas with ethanol. We only use pure gas in everything.
Posted 2012-02-18 11:54 PM (#141202 - in reply to #141130) Subject: RE: Generator Trouble
Expert
Posts: 3853 Location: Vermont
Originally written by AJS on 2012-02-17 10:27 AM<BR><BR>I have the Onan MicroQuiet 4000. The fuel pump WAS a Carter P61145S. It's 90" from the floor (where the bottom of the tank rests) to the ceiling. The pump is positioned 34" up from the floor. Once the fuel gets to the roof, it makes a turn, and travels roughly 8' to the gen itself. I don't know of a pressure regulator on the system...
Well that pump should be pumping at least 4psi...if it isn't then lift could be an issue...I'm assuming you have checked your fuel filter and it is NOT gunked up.Finally if you are using ethanol-laced gas...make sure you are using Marine Formula Sta-bil,it seems to their best for ethanol
Generator Trouble
