dickandlois

The subject of GFI issues keeps popping up, So give credit to the author of this information. It is well done and to just take snippets out of the article would not do the subject justice. The original web link is provided at the top of the PDF file to explore the issue in detail. The attached PDF file is just a small portion, but for most Coach and home owners offers the basics. Rich. Ground Fault interrupter Physic.pdf

Carl, the charts I have posted regarding the power loose at altitude are excellent as a relative reference. When one wants to know the drop in HP at elevation = A little lower output in KW, but the voltage is steady at 120 volts in most cases. Condition of the filters and carburetor or inches of LP settings being off can cause surging - that issue will change frequency and frequency has a direct affect on voltage when the generator speed drops. Be it 1,800 for a 4 pole or below 3,600 for a 2 pole system. Diesel generators are not affected to the same, but they do loose KW per 1000 ft. changes. When running they Tend to be more frequency stable , but one has to remember that diesel powered units have more HP to start with. Clear as modded water . Your background and sight work most likely exposed you to some interesting challenges. The coach is protected with a surge protector, but when there is a storm in the area , I just disconnect from the riser and run the inverter if necessary. Very seldom been where we needed to run the generator. Major grid damage an it has run for a few hrs . Rich. Carl, was it your model year that had the recall on the power panel circuit breakers ?

xrvfczm4, Welcome to the FMCA Forum ! You mentioned that trouble shooting is not one of your shill sets, How about working with 120 volt / 50 amp power circuits? The most common item that causes GIF to trip is a abnormal resistance between the Neutral and Ground buses in the AC power panels, Connections at the ATS, in the 4 in. square "J" connecting the generator output to the wiring going to the ATS and Loose connections caused by the Connections at the ends of the shore power cables. They tend to loosen as we drive the coaches down the road or the plugs ans sockets from use. Many coach owners have a yearly check list that includes tightening all the neutral and ground terminals located around the coach. If you are not sure of working to tightening them - have a service tech go through all of them. No power to the coach from the generator, shore riser or inverter(inverter turned off). Rich.

Afordeck, When you get time from taking care of your corn and coon issue. Could you post the millage on your coach, the year(thinking 2002 to 04) and if the lift pump had been changed before this power issue came up. No Noise on the thread for a couple of days - thinking you are still roiling or have gotten home. Rich.

The real issue is the regulator is sealed / potted in a silicon type compound and it is not the easiest stuff to remove with out causing peripheral damage.. What reading did you get on the slip rings and brush resistance of the winding's listed on page 6 lower right hand corner??? Rich.

Mike, There is a standard parts replacement when doing the repair on the 7.5 / 8 KW units at the 1000 hr. mark. Replace the air filter, fuel filter, fuel pump, the water pump drive belt,(Water pump?) check the glow plugs(They often just replace them because of the labor involved in dropping them) check injectors and check the system control board. The oil filter and oil is replaced. The unit should be then tested before being reinstalled !!! So ask questions - as a general practice take a picture of the connection in the 4 in. square "J" box where the generator output interfaces with the Coach wiring going to the ATS. There are a number of items that need to be removed to allow the unit to clear the opening. Go over the process with the shop shop job writer. In your case add coolant and radiator. What coolant do you run in the coach engine? will it work for the generator. Same coolants means one less item to carry. Rich. Cumming Onan Texas. 39. Cummins Rocky Mountain 14333 Gateway West El Paso, TX 79928 Toll free: 800-800-4240 40. Cummins Southern Plains 7045 N. Loop East Houston, TX 77028 Toll free: 800-474-7421 Oklahoma 34. Cummins Southern Plains 16525 E. Skelly Dr. Tulsa, OK 74116 Toll Free: 800-722-2743

Glad you are back on the road ! The fuel supply, pressure and or flow rates are not monitored by the Engine ECM. When you get home and have a little time could you offer information on any Error Codes the where found. No power and no codes should indicate that problem is before the injection pump. First test for no power in this case would be to every thing from the injector pump back to the fuel tank. As a side note Cummings has had issues with school buses and RV fuel supply lift pumps using the ISB series engines. One can install a simple In line pressure switch that turns on a LED light when the pressure drops below 5 psi. When it lights you are getting warning of an issue(s) in the lift pump plumbing. The pump is failing, there is a restriction in the fuel filters or the is a connection or small hole in the fuel line between the lift pump input and the fuel tank. One can also install a fuel pressure gauge line from the output of the lift pump and plumb it to a dash area pressure gauge. A more costly way to go, but one knows the fuel line pressure at any given moment. Next time look at installing an after market lift pump and keep in mind that the OEM pumps tend to fail at 25,000 miles give or take a few thousand. Safe Travels Home ! Rich.

Carl, Surprisingly Exide sells a number of Seconds - that have been refurbished. Rich.

Frustrating , but an easy fix. The EMS system reading should have indicated an issue indicating the missing L1 or L2 source. Thanks for posting the information on the cause ! Rich.

A fordeck, Have Read the entire thread and a few items are missing !!! What is the Model Year of your coach? How many miles on the coach? OEM lift pump or has it been replaced? What is the fuel pressure at the input to the injector pump? What type injector pump is the engine using ? Bosh VP-44 or a High pressure common Rail type injector pump? The Engine is a Cummings ISB, IF it is a ISB-02 series there is a third fuel filter in the fuel supply line between the fuel / water separator filter and the lift pump. In line fuel filter used on the Cummings ISB-02 series engines installed in Freightliner Chassis. Fuel Filter part number Inline ISB-02 Series. RAI 025RAC10 Rich. PDF file that shows the location. NOTE ! They have been found in slightly different locations in the RV chassis. One popular location is in the drivers side frame rail just behind the rear Axle. Tight spot and vary hard to find. Know of one the was in the area of the Right frame rail. Cummings ISB-02 series engine - it is in the fuel supply line. A number of trucks have it located in a clip mount . In-line_fuel_strainer_for_ISB02.pdf Check the fuel flow - No flow, Low flow or low pressure - this is what you are looking for, the unknown item for many shops !! You might want to look at this thread - that offers some information on Cummings Fuel lift pump issues.

DD69, Did the control arm bushing lack grease fittings ? Rick.

Very Good point! I have run across batteries with water in one of the cells.(No Acid at all) When buying wet celled batteries - have the installer check them BEFORE installing them is a good proactive move. Rich.

Thanks for the information. The fact that there was a loose connection at the rear of the coach, that would cause issues. The tech mentioned a loose connection, very well could mean the main 12 volt bus connection was at the rear of the coach. This circuit often has a sealed 100 to 150 amp fuse that feeds power to a common 12 volt terminal up front near the drivers side area. where the other fuse box terminals get 12 volt power form branch lines connection to this main power source. (You did mention that the solenoid was changed 2 mounts earlier if I'm interpreting you information correctly) The solenoid very well could have failed, due to damaged high current contacts. The other circuit numbers are sub feeds from the solenoid and the terminal lugs where redone and sealed. (Makes sense-one does not want to have a coach comeback for the same issue, fuses where replaced - Just replace them - a constant on and off issue can cause a domino affect down stream from the primary supply point.) I would almost put money on the fact that some of the time was looking at electrical drawings - that enabled the tech to trace the wiring. They did print out a an OK list of the work and parts used. The connection at the rear that powers the solenoid, start and run circuits and everything off the fuse panel is one standard method to power the drivers station. Rich. Note - Think you might want to ask for the Chassis wiring PDF file to have on hand. You do have one family member that works in a field with a number of items that require DC Power. They build a house on wheels and we shake and rattle them down the road. SO many of the electrical issues are the result of thing loosening up !!!!

The last squeak issue I needed to address was caused by fuel and vent lines rubbing against locations on the frame and chassis. Wrapped the lines locations that where rubbing with neoprene. Noise gone. The hardest part is finding the item(S) that are moving . Rich.

Pippins, Thanks for the update, glad things are working. I think you should ask for a brake down of the 9 hrs. Labor, Traced from what bulkhead(location) Down to the bus circuit breaker(Breaker location and number) and the location of the relay / Solenoid. What part of the solenoid failed ? Contacts or activation coil? The circuit numbers that the ECH ST85 solenoid supplied power to and is the coil powered from the ignition switch or sub circuit. Rich.

Peter, this is the Meritor PDF file that covers the parts layout a contact number and what information is needed to match up items. The catalog is extensive, but is broken down into the different parts by chapter / sections. Think looking for a kingpin kit might be the best way to get all the parts needed to do a good repair! I have not succeeded in finding a good cross index number using the information offered, the age of the parts and the likely hood of them not being entered into the current computer data base is a possibility . Think you can find what is needed. Rich. Meritor_front_axle_parts_PB8951_Eje_Frontal.pdf This link might help as a contact for information. https://www.meritor.com/Contact/default.aspx

ronivera55. Welcome to the Forum! From your post it sounds like there is air valve not closing or a leak that is more pronounced when traveling. You best move would be to have the air ride system looked at. Rich.

The Module is a sealed unit and with no information on the armature winding or wiring for the unit. I doubt that there is a pot to set. I must admit that I have not been a fan of some of the control systems used. They know that there is a heat issue and heat kills electronics. I know that your aware of the one alternative for the module, that is in a metal case. personally I might try one and see if it can be mounted to a heat sink that allows for more airflow. Thing is - is there enough room to mount one and still install the covers? Note! Ask if you buy a new module and that does not remedy the problem. Can it be returned. Although it might be best just to have a shop run some diagnostics before going ahead with any more investment. Rich.

There is no reference to resistance information you offered. This is a PDF file that I put together - in hopes that it will explain the dynamics of how the regulator works in this specific case. The Voltage to frequency chart did get clipped on the right side, but 80% is displayed and should be enough to understand the regulator interaction to speed and current in the armature winding to maintain a constant 120 volts at 60 cycles in this case. The voltage to frequency chart IS US-FULL if only the RPM's are low. The rest is a Z number generated inside the regulator to keep things set at 120 Volts. Rich. Onan Voltage Regulator_model-305-manual.pdf The Last page 6 Bottom right corner offers some resistance tests and information covering the Generator field coil resistance and information on cleaning the slip rings and brushes. My Bad. Totally missed this information. Concentrated to much on your resistance reading. Getting to the slip rings and brushes might require removing the generator from the coach and if you attempt this - please take a number of pictures so reassemble is possible. GENERATOR Checking the rotor DC resistance is particularly important before installing a new regulator. This is your chance to find out if there is a problem that possibly caused the last regulator to fail. Unplug regulator. Measure the resistance between pins 9 and 10 on the connector that plugs into the regulator. It should be between 23 and 28 ohms. A reading much lower than 23 ohms indicates a partial short in the rotor. A reading much higher than 28 ohms indicates a problem with the brushes, slip rings or a bad connection. The most likely cause will be dirty or oxidized slip rings so check them first and clean if necessary (See Slick Stick, Pg. 9). If the resistance is still high, check the brushes and connections. If possible, check the stators for grounds (See G-MAN, pg. 9). Make sure that the field flash voltage is reaching the regulator by measuring 12 VDC on pin 7 to frame ground during cranking. No voltage indicates a control board or wiring problem.

Bingo !!!!! A little piece of cheese !!! Can you list the fuse's that do not have power - then I can try to trace the power back to its source > Think the drawings I chose are real close to how your fuse panel might be wired. There is a strong possibility that the main 12 volt power feeder is loose at the supply point or the wire connected to the feeder buss has opened or somehow disconnected. Good work !!! Rich.

Sure sounds like and issue with the front Harness. All the front lights - turn signals, head lights(both high and Low) Do you have any Marker lights (exterior) Dash lights, Do the Wipers work when the Ignition switch is set in Accessory position ? Does the heater blower motor run? Could be a bad ignition switch wiring harness - those connections have been known to fail do to heat. Reaching for straws at this point and items that are easily check . There are sections of the fuse box panel that are powered on different 12 volt feeds going to the fuse box(s) The Engine starts and that circuit is power by one of those primary 12 volt heavy gauge wires. Rich The wiper and driving light circuits are split out of the harness so they can be connected to the different locations at the drivers set.

Rod, I had to replace the radiator in my coach, Second owner shortly after purchase - covered under a warranty. My issue was caused because the previous owner took the coach to Alaska and did not clean the bottom of the coach to remove the calcium chloride. That made a mess of everything, but a good dealing chip for us. Living in a state that uses tons of salt and other chemicals to melt snow, requires one to make cleaning the radiator and underside a TOP priority. As a side note ! In the spring driving the coach does not happen until a very good rain has washed the dust off the road surface. Rich.

Ross, I have placed a 1-1/2 in. hole in the left bottom corner. Starting with a pilot hole in the proper location, makes the job easier Started with a pilot hole a little smaller then the a hole saw center drill. The very corner is tapered or curved ! To place the hole as close to the corner as possible. Then use a engine spray cleaning wand that draws the extreme mixture out of a bottle and held in place so I do not spill the bottle - keep the tube in the bottle with a hole just big enough to keep the end at the bottom of the bottle. Air Pressure set at 100 psi and the wand fits easily into the opening, allowing we to thoroughly clean the left side, corner and bottom of the CAC and Radiator. The Right side is much easier because of the fan blade pitch from inside . Rich.

gpippins, Sounds like you have a connection point that is disconnected. The simple answer. Does your coach have a Smart Wheel ? That item can change the way things are connected, Smart Wheel have an added control module - so one can control items mentioned right from the steering wheel ! Need to Know A number of the items are in what one refers to as the front run harness ! This harness connects to the items listed and the connection is most often located behind the dash and close to the harness that runs down the steering column. Pass on some information on how and where these item are controlled. Instrument panel and or Console. Information is key to knowing where to start looking for the needed harness information. Rich.

Herman, I know you are informed about axle weight, but when was the last time you where weighed ? When was the last time the ride height was checked ? The REV Group height control valve looks just like this. and this is the Freightliner ride height PDF File. Your chassis is made by ? ,but could be the same or slightly different Rich ride height adj.pdf One needs to read the information as the air pressure is remover per instructions to adjust - not the safest place to work