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FS2020

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Posts posted by FS2020


  1. I think I solved the problem of the coach batteries not charging when on shore AC:

    The coach battery disconnect relay feeds into a ShortStop 40A circuit breaker. I just realized that there's a little black button that resets the Shortstop breaker. I pushed the reset and it started charging the coach batteries.

    I feel kinda dense for not noticing the Shortstop reset, but it is not marked and there are no directions. I'm an engineer but I have no experience with RV electrical systems. I basically had to figure out the entire battery disconnect and charging system. I have spent at least 50 hours on this problem. I took the RV to two RV repair shops around Pittsburgh and neither one of them would even try to diagnose the problem. They said they repair RV's but electrical systems are too complicated for them. I must agree.

    I tried to attach a photo of the Shortstop breaker for others, but it won't let me. A window pops up and asks for URL to the image. How do I attach a photo to my post?

    To see if the problem of parasitic drain had been solved, I disconnected shore AC and measured 12.58 V on the coach batteries. 18 hours later the coach batteries were at 12.49 V. Now that the batteries are being charged by shore AC, the 40A AC-DC converter should easily cover the parasitic load when on shore AC.

    We're going to sell this RV and buy a newer, smaller one -- and I'll be sure to buy a shop manual with it!!!

    Thanks everyone!

    Frank


  2. Frank,

    From your information regarding the voltage dropping to 2 volts from the coach batteries. One would think there is a defective Counter EMF diode in the wiring between the relay actuation 12 volt supply and the switch? A resistance reading between the fuse and the 12 volt connection at the battery (12 volt wire removed at the battery post )might give you the same reading both ways and a resistance of between 30 and 40 K ohms. Didoes are nice devices, but when they fail and there is no information regarding their presents, it can become a hair pulling experience.

    Do you measure 12+ volts at the rocker switch from the coach 12.5 volts?

    If not then the culprit could be between the fuse and the switch. You could read the voltage at the fuse coming from the battery, think you mentioned it was low in a previous post? In that case its in the main wiring harness between the coach batteries and the coach builders fuse.

    Thing is its working, but if the current solution causes some strange problems down the road you might consider adding a diode to the supply side of the switch. Needs to be installed in the proper orientation to work!

    My instincts tell me one thing and the math says something else,regarding the resistance reading I think you would get; so I will need to ponder the thought a little more.

    Rich.

    A resistance of 7 ohms, with a current of 1.5 amps would drop the voltage to 2 volts. So a bad connection / splice or corroded connection could be the culprit. That would mean a power drop of 15 watts. Something should be a little on the warm side!

    Each rocker switch is supposed to receive 12V. Then the switch sends + or - 12V to the disconnect relays to open/close the relay. The chassis rocker switch is receiving 12V. The coach rocker switch is receiving only 2.5V. I just connected the 12V supply from the chassis switch to the coach switch, and the coach switch now works.

    But I think you're right, I could have a short somewhere in the wiring to the coach rocker switch.


  3. Thanks to your expert advice, I have the battery disconnect relays working now. But power from the coach batteries is not being delivered to inside the RV. The chassis power works fine and the engine starts.

    The power from the coach disconnect relay goes through a "short stop" breaker that is labeled "Short Stop 24V D33 4OA." (I tried to attach a photo, but it asks for a URL. When I tried a URL is gave an error?)

    I jumped it with my multimeter and 1.5 A is flowing through it. That's only 18W at 12V. Is that too much for a normal drain from the coach with everything off?

    In any case, I'm going to replace it and see what happens.

    Thanks,

    Frank


  4. Update:

    I took apart the Power Distribution Panel and verified that the Intellitec Battery Disconnect Relays are working.

    Inside the door of the RV are two rocker switches that open/close the Battery Disconnect Relays. The switch for the coach batteries was only receiving about 2 V. It needs 12V to open/close the disconnect relays. So I jumped the 12V feed from the chassis switch into the coach switch, and it now the coach disconnect relay works.

    Also, the coach batteries are no longer being drained by a parasitic load.

    Some progress, slowly.

    Thanks,

    Frank


  5. Thanks so much for the service manual Rich! I had been trying to find it for a long time.

    I started it again and let it run for awhile and the engine speed gradually slowed down to normal. It ran for about 20 minutes then shut down.

    I'm hoping I've brought it back to life, with good advice from this forum.

    Thanks,

    Frank


  6. OK, I got the generator to start! But it sounds like it's running at full speed so I shut it down after a few seconds.

    I'm thinking the linkage that controls the carb is stuck? Any other thoughts?

    I agree completely with Kay: I need to run the generator on a regular basis to keep the brushes and carb clean.

    Thanks everyone!

    Frank


  7. I flushed the carb with concentrated fuel injector cleaner and let it sit for 24 hours. I've verified that it's getting gas and the fuel pump works, it's getting spark, it's getting 12.7 V from the batteries.

    I tried several times a day for several days to get it to start.

    So I've given up and scheduled an appt with Cummins Onan near Pittsburgh. It's a one hour drive each way. Last year it cost me $150 to fix this problem.

    I will post what the Cummins Onan tech's say was the problem.

    Thanks for trying to help!

    Frank


  8. Frank,

    Sounds like the needle valve in the Carburetor is stuck. happens when they set with no fuel / stable in the bowel.

    Fuel should try to work its way into the carburetor.

    Just let it set, then keep trying to get it to run. Once that happens, keep an eye on the carburetor for leaking fuel. stop the engine and let it set some more, things could just clean them selves with time.

    See if the problem will clear before getting into the carb.

    Rich.

    Thanks Rich, I just made a mixture of 8 oz of fuel injector cleaner (enough for 20 gallons of gas) and 8 oz of gas. I fed it through the fuel intake line. So the carb bowl is full of concentrated fuel injector cleaner and hopefully it will dissolve the gum. I will let it sit for a few hours and try it again. Thought I would try that before taking the carb off. That also verified that the fuel pump is working.

    Will let you know the results. Frank


  9. I added carb cleaner to the gas and sprayed carb cleaner into the carb, then let it sit for a few hours. I removed the air filter and sprayed starter fluid into the air intake.

    It sounds like it's firing when I hold the start button down, but as soon as I release the start button, it shuts down.

    I've tried to start it at least ten times, hoping the clog in the carb would clear out, but it hasn't (if it's a clogged carb).

    What next?

    Do I need to pull off the carb and soak it? I'll verify I'm getting gas and spark first.

    Thanks,

    Frank


  10. Frank, got to say that is strange, you mentioned removing the Body Builder fuse removed the parasitic load from the Coach batteries. Even thought the fuse is in a fuse box under the dash.

    1.5 amps is going somewhere! The fact that it is loading the coach batteries, would make one think something related to the coach circuits..

    Do you have power operated steps / and do the coach and chassis disconnect relays still work?

    Rich.

    Rich,

    Good call. You are right, even though the fuse is in the chassis fuse box, it is causing a 1.5A drain on the coach batteries.

    The Intellitec disconnect relay for the coach batteries is not working. I have ordered a new relay and new switch panel.

    Helps to have a second set of eyes!

    Thanks,

    Frank


  11. I have an Onan 4.8kw gasoline generator in my RV, Model 5BGEFA26100N, SN H973723191.

    It cranks and sounds like it's firing when I hold the crank button down, but when I release the button, the generator shuts down.

    Last spring I took it to an Onan/Cummins shop and they got it working. They said "the brushes needed cleaning" or something like that.

    We didn't use the RV last year, so the generator sat without being used for a year. Now it's doing the same thing, cranks and sounds like it firing when the start button is held down, but stops as soon as I release the start button.

    Thanks for any suggestions!

    Frank


  12. Frank,

    The fuse labeled "Body Builder Access Feed (run only)" Thinking it powers the monitoring system / the battery disconnect circuits and LP detector plus a few others.

    Looking for item(s) that do not operate. is one way too narrow it down.

    The other tool you could look into is a circuit tracer.

    They work well for finding where the wires run between too points.

    They come in a wide price range. The tone generator, puts a tone on the wire and the level needs to be adjusted lower to narrow down the exact wire; by using the receiver portion.

    Lowe's has them and you can search the web for circuit tracers to get an idea of the price range and even look at a user manual(s) on line (with Make and model)to find one you feel will work.

    It takes time and a learning curve, but one can get very good at finding circuits with practice.

    Rich.

    The fuse labeled "Body Builder Accessory Feed (Run Only)" is in the chassis fuse box under the dash. So the fuse is for a chassis accessory. I think Ford called it's electrical chassis system "Body Builder" for RV's. I cannot find anything that stops working when I start the RV and pull out the Body Builder Access fuse. The engine runs. The lights, AC, windshield wipers all work.

    What other chassis accessory could there be that is only turned on when the engine is running?

    Thanks,

    Frank


  13. Have you looked for a battery isolater, maybe diode based, or relay operative. Most coaches have one, and yours may have gone bad. Just a thought, since you have now tested using a known good battery charger.

    There is an Intellic relay based battery disconnect system. Just inside the door are two rocker switches that activate battery disconnect relays. Is that what you're referring to?


  14. A bit more info about my coach batteries not being charged when I'm plugged into shore AC.

    I took the DC output leads off of my PowerSource PC 50 converter, and connected the leads to a high current 12V battery charger.

    But still no power reached the coach batteries. So the link between the AC-to-DC converter and the coach batteries is broken somewhere...

    Thanks,

    Frank


  15. YES! Thanks to the advice from this forum, I found the parasitic load that was draining my coach batteries!

    I removed the negative cable from the coach batteries, then connected my multimeter between the negative cable and the negative terminal of a coach battery. It showed that 1.5 A was being drained from the coach batteries.

    I then measured the voltage drop across each fuse. One fuse had a 200 mV drop across it!. I removed that fuse, and that completely stopped the parasitic current drain from the coach batteries. The fuse is labeled "Body Builder Access Feed (run only)" Does anyone know what that is???

    Now I just need to get the coach batteries to be charged when I'm connected to shore AC. When connected to shore AC, no charging power is delivered to the coach batteries.

    vielen veilen Danke!!!

    Frank :)


  16. Frank, welcome to the new owners learning curve !

    Good post regarding the location of the fuse panels !

    Could you post the chassis make and I will see if I have some fuse panel info.

    The one on the firewall / dash is for fusing the chassis items, lights, dash AC and heater motor ext.

    The ones in the engine compartment are the primary panels for the engine and the fuel pump, ignition, ECM, Most likely the entry power steps, ext.

    The one under the bed , slide out power, leveling jacks and holding tank monitor power, and power for activating the relay(s) in question.

    The one next to the AC breaker panel would power all the 12volt lights, roof fans, water pump, plus.

    I was thinking of suggesting removing the fuses to find the phantom loads this A M before I opened your post. Pull one fuse at a time from the panel. then use a test light across the fuse gap. if it lights that circuit is drawing power.

    The charging voltage, should be present on one side chassis and coach relay. reading from ground to all the large terminals of the relays. That voltage should be close to the same from both the engine alternator and shore powered convertor.

    Rich.

    All,

    My RV is a 1998 Thor Four Winds Windsport. The metal sticker under the dash says the vehicle ID number is 3FCMF53G4VJA22935 and the Model Number is WA04698.

    I had AutoZone test my batteries today. All are at 12.5 V and producing 550 CCA. They are rated at 875 CCA. So they are somewhat weakened. I am pretty sure there is a large parasitic load. The parasitic load drained the batteries a few times. That's probably why they are weakened. I need to find the parasitic load before I replace the batteries.

    This evening I will put a volt meter across each fuse to try to detect the parasitic load. I have a good multimeter that should detect small millivolt drops across a fuse.

    I think i should also replace the Powersource PC50 converter. It's output is rated at 12VDC at up to 50A. This converter is no longer made. Can anyone suggest a good replacement?

    Thanks to everyone for the excellent advice!

    Frank


  17. Frank, look in your AC circuit breaker panel and see if you have a tripped 15 Amp breaker.

    From the information I have, it looks like most of if not all the convertors are fuse at 15 amps AC.

    Regarding the Charging from shore power it should read very close to the same reading you are getting from the alternator.

    You should have a 12 volt fuse box that is power from the batteries and the convertor when things are working properly.

    How many fuses does your panel have and what is the total amperage when you add the fuse size numbers up?

    If the relays are always drawing current, that will be part of the load always present, if they are latching relays then that load is only temporary, until the relays latch in the on or off position..

    The switches on the inside control panel, look like rocker switchs.

    Rich.

    Rich,

    There are more fuses and breakers in this RV than I can shake a stick at! There's a fuse box under the rear bed, a fuse box under the dash, a fuse box inside the power dist box, and two more high amp breaker boxes in the engine compartment.

    I think I need to systematically remove fuses and see if the batteries stop draining, until I isolate the load that's draining the batteries.

    In addition, I need to understand why the coach batteries are not being charged.

    The Intellic disconnect switches are not always working, so I'll start by replacing them.

    I've helped to solve some national level crises, but this one has me pulling my hair out!

    Frank


  18. What size and how many batteries make up your house battery bank (in amp-hrs best)? Basically want to see how many amp-hrs "disappeared" in those couple of minutes. 13.2 shows a totally charged battery bank (actually 12.7 is a fully charged 12 volt battery-- anything over about 12.7 is just surface charge). 12.2 VDC is a 50% discharged battery bank.

    Guess my point is if you have 200 amp hrs of house battery bank and within a few minutes 100 amp-hrs went somewhere, that is a HUGE amount. As an example, a 1500 watt microwave would need to run for over 40 minutes on the battery (with inverter) to use that much power. Something is wrong here-- that is why I mentioned fully charging and then load testing the batteries.

    Wolfe10,

    I have one 12V auto battery for the engine/chassis and two 12V deep cycle batteries connected in parallel for the coach. I will get the specs for you later (it's cold and dark in Pittsburgh now), but they're typical 12V chassis and coach batteries.

    I am going to do some tests to try to find the large load that's draining the coach batteries. I will charge the coach batteries, then remove fuses from certain 12V circuits, and then connect the batteries. When the coach batteries stop draining, that should track down the load.

    However, I am still faced with the problem that my coach batteries are not being charged when shore AC is connected.

    Thanks,

    Frank


  19. Frank, thanks for the information.

    Looking at the pictures you posted, are they of your coach system? The right hand relay labeled Chassis. There is a copper link / strap with nothing connected. Below it looks like there might be 2 gray wires connected to it.

    That should be a ground.

    The coach batteries should be connected at this point, positive on the left

    The other relay labeled chassis has a red wire on the left and a black wire on the right. What is the voltage reading from ground to the 2 red wires on the left side of them?

    Get a reading when connected to shore power and when disconnect from shore power and post the readings.

    Rich.

    See you got a reading with the engine running. at the relays with the engine running and the engine stopped, what reading do you get?

    Rich,

    The photo is of the power dist box that has a disconnect relay for the coach batteries and a disconnect relay for the chassis battery. Power from the batteries enters through the two copper bars in the center (see red arrows pointing up). The cables labled S and I are from the rocker switches inside the RV that activate the disconnect relays. When activated, the relays connect coach and chassis power to the RV.

    The voltage in and out of each relay was 12.3V, the same with and without shore power.

    I'm still trying to figure out why the coach batteries are not being charged by shore AC. That might solve the problem, even if there's a large load on the coach batteries.

    Thanks,

    Frank


  20. Wolfe10, Thanks again for helping me troubleshoot this!

    All of the batteries are new. They've been on a float charger and were at 13.3 V today before I connected them to the RV two hours ago.

    Now the batteries are at 12.4 V. Seems like something is drawing current from them. And they are not being recharged by shore AC.

    I will pull out the batteries and test them, but I doubt that they are bad. if they are bad, somethnig made a new battery go back very quickly.

    I'm starting to think that something is broken (a disconnect relay, heater element, etc) and is shorting to ground and draining the coach batteries. But no fuses are blown.

    I remain bemused.

    Thanks,

    Frank


  21. Thanks for the thoughts Wolfe10

    I measured voltage across both chassis and coach batteries with the engine off, and both are at 13.3 V. I started the engine and let it idle at ~900 rpm. The voltage across the chassis battery was 14.9 V. The voltage across the coach batteries dropped to 12.1 V.

    I'm perplexed. Why would the coach batteries drop from 13.3 V to 12.1 V when I start the engine? It's almost like a load is applied to the coach batteries when the engine is started.

    When the engine is off and I'm connected to shore power, there is no power applied to the coach batteries.

    Sorry about my confusion of invert/convert. The Powersource PC50 takes 120VAC and converts to 12VDC.

    Any thoughts appreciated.

    Frank


  22. Thanks Rich

    The Inverter is a PowerSource PC50 producing up to 50A at 12VDC.

    The alternator is charging the chassis battery just fine, and I've verified the output of the alternator. But I don't think the coach batteries are charged by the alternator... is that correct?

    Does anyone know if the Battery Disconnect system also disconnects the coach batteries from the PowerSource charger? I've had problems with the Battery Disconnect for the coach batteries.

    Thanks!

    Frank


  23. I have a 1999 Four Winds Windsport RV. The coach batteries are not being charged when I'm connected to shore power. I've verified this by measuring the voltage at the battery terminals when on shore power. There is no change in voltage when I connect to shore power.

    I have checked the 120VAC to 12VDC inverter that I assume is supposed to charge the coach batteries. It produces 13.5 VDC (with no load) and powers all of the 12V components in the RV.

    The RV uses an Intellitec battery disconnect system. Inside the door are two switches to disconnect the chassis and coach batteries (see photo below). Also below photos of the Intellic disconnect relays inside the power distribution box that's in the engine compartment.

    I'm an mechanical engineer and I have spent a huge amount of time trying to fix this. So I will be immensely grateful if anyone has suggestions.

    Best regards,

    Frank

    post-37376-0-14052100-1397581999_thumb.j

    post-37376-0-74249000-1397582010_thumb.j

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