Ok. Here we go. My mom bought a 1995 four winds class a motor home. It's in fair shape, but I have generator problems. I tried to start it, But it wouldn't fire, it would turn over, but wouldn't fire. So I didn't touch it for a while and apparently my hillbilly uncle was going to fix it. So he yanked the whole thing out, and took it , to his house. He told her it needed a new starter which I knew she didn't cause it cranked fine, but she didn't believe me. Needless to say he couldn't get it running. So he sent it to some other hillbilly shop that said they worked on them. After 6 months of sitting in their corner I decided to pick it up. I brought it home and was wondering why he said it needed a new starter. I hooked it up to a battery to make sure it cranks and it won't. All I hear is what I think is the plunger moving back and forth on the carb. I may have ruined it because the 1st time I messed with it I plugged power up to it and my mom told me there is a switch to go from gen power to ac power and when I plugged it in I fried it.. But she knows as much as I do about it. I know if I can get the engine running I can figure out the rest. I ha tee e to throw a new control board on it if there is something else.
onan generator help.. please!!!
- Thread starter grimmjj
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Ok. Today I finally got my meter. I'm producing 14.4 volts when it sits. As soon as I push the start button, it drops to 6.2 volts. That's the assumption to why it won't start. I'm getting a new battery today and seeing if it will turn over. I'm guessing it will. I still h ave this engine sitting on the ground. Do you think it's possible to get this thing running without being hooked up to the motorhome? I hear people say that the engine won't run unless there is a quarter of tank of gas. Is there a way to trick it into thinking there is a,quarter of a tank? Hook up some sort of gravity take n k to it from a lawn mower or something? I'm thinking I want to get it fixed right,before I put it back in there. It could be a number of things, but I know if I can get it to crank, spray starting fluid and get it to fire than its a fuel delivery system problem. I mean when I 1st looked at it I scratched my head. The more I look at it the simpler it really is. Any person with a little electrical knowledge should easily be able to figure it out. I'll keep you posted. Also please let me know any suggestions that could help me.
carson
Well-known member
Interesting, the first SOLO post I have ever seen with questions and answers.
How can we help. I hope we can
How can we help. I hope we can
Bobtop46
Well-known member
Don't know where you should start. Yes it needs 1\4 tank of gas if it is installed, it also needs a good ground. I would install it, hook everything back up. Ensure the gas is good, good ground, 2 well charged house batteries, start the RV, adjust the altitude setting and then try to start it and see what happens. If you are lucky it will turn over or at least give you a fault code. From there you can fix it based on codes, short of that good luck.
HueyPilotVN
Well-known member
You can use a fuel can with a gas line to your generator if you do not have enough fuel in your main tank. This will also eliminate the issuse of a fuel tank or line and pickup problems.
MT4Runner
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It's an internal combustion engine.
Suck-squeeze-bang-blow...but first it has to turn before it can fire!
It's kind of hard to understand from your post. If you have 14.4V, is the motorhome engine running? That's too high of voltage for a battery at rest. You then mention 6.2V when hitting the start button. The starter will pull a lot of amps, but I can't see it dropping the battery that low. I also can't see the mechanical fuel pump moving without the engine turning over. Is the starter turning it over or not?
The fuel pickup is 1/4 the way up the fuel tank in the motorhome. If the motorhome has less than 1/4 tank of fuel, the generator sucks air--that way it doesn't run you out of fuel and strand you. If the motorhome has more than 1/4 tank of fuel per the gas gauge, that's probably not it. Once you turn it over, it only takes 10 or so seconds of cranking for the generator's fuel pump to prime an empty hose and suck fuel to the carb.
If the generator engine isn't running, it's an engine problem, not an electrical problem!
Suck-squeeze-bang-blow...but first it has to turn before it can fire!
It's kind of hard to understand from your post. If you have 14.4V, is the motorhome engine running? That's too high of voltage for a battery at rest. You then mention 6.2V when hitting the start button. The starter will pull a lot of amps, but I can't see it dropping the battery that low. I also can't see the mechanical fuel pump moving without the engine turning over. Is the starter turning it over or not?
The fuel pickup is 1/4 the way up the fuel tank in the motorhome. If the motorhome has less than 1/4 tank of fuel, the generator sucks air--that way it doesn't run you out of fuel and strand you. If the motorhome has more than 1/4 tank of fuel per the gas gauge, that's probably not it. Once you turn it over, it only takes 10 or so seconds of cranking for the generator's fuel pump to prime an empty hose and suck fuel to the carb.
If the generator engine isn't running, it's an engine problem, not an electrical problem!
Lou Schneider
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Here's a link to a very good troubleshooting guide for Onan generators. Flight Systems makes good replacement control boards if it comes down to that, but follow the troubleshooting list first:
http://www.flightsystems.com/pdf/onan-rv-troubleshooing-guide.pdf
The first thing to do is get the engine to crank over. This means having a charged battery and good cables running from it to the generator. While it's cranking, check for spark. Fuel is delivered via a 12 volt fuel pump, so you can use a line from an outboard motor tank connected to the pump's input or a tube shoved into a gas can.
Once the engine starts to run, if it dies when you release the start switch you are either missing voltage from the generator, low oil level or low oil pressure. The control board has to see these to let the engine keep running when you release the start switch.
All of this is covered in the Troubleshooting Guide. Start with "Getting the engine running" and proceed from there.
http://www.flightsystems.com/pdf/onan-rv-troubleshooing-guide.pdf
The first thing to do is get the engine to crank over. This means having a charged battery and good cables running from it to the generator. While it's cranking, check for spark. Fuel is delivered via a 12 volt fuel pump, so you can use a line from an outboard motor tank connected to the pump's input or a tube shoved into a gas can.
Once the engine starts to run, if it dies when you release the start switch you are either missing voltage from the generator, low oil level or low oil pressure. The control board has to see these to let the engine keep running when you release the start switch.
All of this is covered in the Troubleshooting Guide. Start with "Getting the engine running" and proceed from there.
Well. Perhaps I fibbed a bit at the battery. The battery was a battery charger 12v 6 amp charger. The 6 amps aren't enough cranking amps to allow the engine to run. I'm getting a new battery this evening and hooking it up. Please help me a little on the fuel delivery side since I'm not really good at knowing small engines. The engine appears to have 2 fuel filters? 1 is a huge reservoir maybe the size of a cup (8oz) that the fuel goes into from the main tank. Then it travels from there under and appears to come up the front into another small fuel filter about double the size of a sewing thimble. Also I took the top off today and I noticed there is what appears to be some kind of square box that looks like a limit switch attached to a rod that connects to the carb. I'm guessing that's the governer? Well the rod popped off that box so I'm wondering if that was a reason it wouldn't start. Please let me know if I'm right with my thinking. That reservoir is what I'm worried about its clear in the back and if that's a filter I'll have to drop the whole generator again to replace it. What a pain that looks like.
Also since my mom bought this thing is there anything I have to worry about like a switch to switch the power from ac plug in powers to generator power? Or if I get the generator running and all hooked up there's an automatic switch in case I'm plugged in and have the generator on by accident sometime it won't overload circuits. I'm sorry to ask such a silly question, but I'm new to thos and so is my family. I seen relays on the control board when I looked at it today and was wondering if that helps me in case,I or someone would do something like that.
Also
Also
MT4Runner
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Yes, you're going to want a real battery. One thing at a time. Get the starter turning the engine over, then worry about other problems if it doesn't fire.
If her '95 Four Winds is like my '92 Four Winds, the generator powers a 30A jack in the very back of the coach on the outside driver's side. It's in the same compartment as the shore power cable.
You can either plug the shore power cable into that 30A jack, or plug the shore power cable into grid power, but not both. No automatic transfer switch, just a manual choice.
If her '95 Four Winds is like my '92 Four Winds, the generator powers a 30A jack in the very back of the coach on the outside driver's side. It's in the same compartment as the shore power cable.
You can either plug the shore power cable into that 30A jack, or plug the shore power cable into grid power, but not both. No automatic transfer switch, just a manual choice.
So is it possible to run both at the same time or do you switch from 1 or the other? I just want to make sure it's not possible for me to fry this thing. I mean really with all the fuses on the generator I don't see how I could fry much beyond the control power board which is a pretty simple looking thing. Appears to be e seperate relays, a couple capacitors, and a few resistors. I can't tell the path of flow, but I'm guessing all relays switch closed when I hit the start and the starter relay opens to disengage the starter once it's running. Also does Tha t sound right about the governed. I'll take some pics tomorrow. It rained here most of the day and I'm on swing shift and just had my 1st midnight last night. It always takes me a day or 2 to get on nights schedule.
Ok. I got her to crank. It cranks wonderfully and that's all it does. It doesn't pump fuel. I spray starting fluid into the carburetor and it pops and spits the fluid along with a bunch of smoke out of the carburetor back out at me. So after that I tried to put a little gas into the spark plug holes to see , if it will fire and it pops once in a while. I know there is a fuel delivery supply problem, but before I deal with that I have a major issue with the engine itself. Squirting a little starting fluid into the carb.
PCarillon
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Most motorhomes need to be over 1/4 tank of fuel for the generator to run just a away for them to make it so you dont run out of gas and cant drive anywhere to get some
That's the least of my problems. If I took the fuel line and put it into a tank of gas if the fuel pump was pumping the gas would get sucked in. The 1/4 of tank of gas is void at the moment. I put some gas in the carburetor to see it I could get it to fire. Thinking maybe the starting fluid wasn't enough. Yeah. It caught fire. Luckily I got,it put out quickly before everything burned up.lol.
Well the frustration is set in. Dad is thinking maybe it's out of timing. Anyone with small engine knowledge please help. Am I going to be tearing this whole thing down? I'm not opposed to it. But I would rather not if I don't have to.
Well the frustration is set in. Dad is thinking maybe it's out of timing. Anyone with small engine knowledge please help. Am I going to be tearing this whole thing down? I'm not opposed to it. But I would rather not if I don't have to.
gwcowgill
Well-known member
From what you are saying, it sounds as though the valves may be stuck in the open position. Remove plugs and do a compression test.
catblaster
Well-known member
The chance of it being out of time is not likely. It has a gear driven camshaft and the breaker points (if it still has them) are operated from a pin riding on the camshaft. Not like an auto where a distributor can be knocked out of time or chain driven cam which can jump a tooth.
Like cwcowgill said ....check for compression, also it is not uncommon for a carburetor to catch fire when gasoline is poured into it from the top. Especially if a valve or two is stuck open. Usually when they do catch fire just keep on cranking and the motor sucks the flame in.
If yours is like the BGA I have on the shop floor it has an electric fuel pump, check to see if you have current routed to it and see if it pumps fuel thru without the carb hooked up. It also had two stuck valves last week when I got it.
Like cwcowgill said ....check for compression, also it is not uncommon for a carburetor to catch fire when gasoline is poured into it from the top. Especially if a valve or two is stuck open. Usually when they do catch fire just keep on cranking and the motor sucks the flame in.
If yours is like the BGA I have on the shop floor it has an electric fuel pump, check to see if you have current routed to it and see if it pumps fuel thru without the carb hooked up. It also had two stuck valves last week when I got it.
Thanks.. from here I'm going to need help. I have no idea what compression needs to be. This will take a couple days. I'll have to get a compression tester from some of my red neck friends. They all have them I'm sure. If I have low compression am I screwed?
The fuel pump I believe is the little thing right after the what looks like a cup where the fuel line hooks up to. It has 2 wires hooked up to it. Its much smaller than I expected :/ it to be. I'll take a picture of it tomorrow and post it here just to make sure I'm looking at the fuel pump.
The fuel pump I believe is the little thing right after the what looks like a cup where the fuel line hooks up to. It has 2 wires hooked up to it. Its much smaller than I expected :/ it to be. I'll take a picture of it tomorrow and post it here just to make sure I'm looking at the fuel pump.
Charlie 5320
Well-known member
Don't take this the wrong way, but you need to take this to someone that has some experience with generators. You may end up screwing it up, and it'll cost you more after you do that. It's probably just a fouled carb. You can run a 12v wire direct to the fuel pump to get fuel. .
I won't take it the wrong way. However that being said I'm an industrial electrician. I may not know much about the engine side of the generator, but I'm positive I know everything past the engine running. I completely understand the generator past the engine. I've taken enough things apart in my day to understand it once it it's explained to me. I've been through 4 Years of electrical school and am positive once I get this thing running I will not ask another question. I know what the relays on the control board do, I understand how the router works, I see the rectifier and understand all the wiring behind it. This is something I can do with a little direction. And if you all can't help me I'm guessing I can find someone who can.
