The Roadtrek Generator

This is the third article in our series of Electricity in the Roadtrek and the second electrical system we are going to talk about. An electric generator is an option when ordering a Roadtrek. If you have a gasoline engine Roadtrek - the Chevy based Roadtreks - you will get a generator that runs on gasoline. If you have a diesel fuel engine Roadtrek - the Sprinter based Roadtreks (with the exception of the new ETrek) - you get a generator that runs on propane.

The generators that Roadtrek uses are made by Cummins/Onan and the gas generator model that is installed will generate 2800 watts* of 110/120 volt AC power. This is enough power to run just about everything electric in your Roadtrek at the same time - with the possible exception of running the air conditioner AND the microwave at the same time*. The generator in my Roadtrek 190 Popular is located under the chassis on the passenger side rear of the van. It is secured to the bottom of the chassis and has an exhaust pipe that runs to the rear driver's side corner of the fan just below the bumper and exhausts to the side. The gasoline generator gets its fuel from the van's gas tank and is connected to it's own gas line. The line* is positioned in the gas tank so that it prevent the generator from operating if your gas tank goes to 1/4 tank of less so that you cannot get stuck and not be able to drive away if you continue to run your generator to the point that there is no gas - you are prevented from doing this.

The generator is connected to the 110/120 volt* electric circuits in the Roadtrek and while the generator is running you can operate the 12 volt lights, all of the 110/120 volt outlets, all appliances, and also charge the coach and the engine batteries. While the 12 volt electrics will be drawing from the batterie(s), the batteries are being recharged at the same time. Be aware that not only is running the generator noisy, but the exhaust is deadly and the exhaust pipe must not be obstructed outside. It is extremely important that you know your Carbon Monoxide detector - located on the ceiling of your Roadtrek over the bed area - is working properly. This will save your life should exhaust somehow come inside the Roadtrek. Do not open the rear windows over the generator exhaust when running your generator.

Many campgrounds have rules about when you can run your generator because of the noise. If you are camping in a parking lot or field where there are other RVs be aware that your generator may disturb those around you. There are certain camping courtesies about this to be aware of.

Anyway - let's get you started using your generator. It is simple IF you follow these steps -

1) Turn on your Battery Switch. You need the battery power to start the generator.

2. Start your van engine. This will give the power to start your generator a little extra boost that will prove to work every time when you are having a hard time starting your generator. Just start your engine and let it run while you go to the next step.

3. Push the generator switch on the wall of your Roadtrek. Push the switch at the top.

 Hold the switch in until the generator motor kicks over and starts and keeps running. If you let go of the switch and the generator stops, push and hold the switch again. You may hear the sound of the motor pulse or rumble. It will catch and run steady.

Switch on the left - Meter on the right is how many hours your generator has run since installation.

4. Let the generator run for a couple of minutes before turning any appliance on. You will hear the sound change to a more steady run - and then you are ready to use your generator's power. If you try to start a large appliance like your air conditioner before the generator is ready, the air conditioner will not have enough power for the compressor to start properly. Just avoid this and give the generator a chance to come up to full power.

5. Once the generator is going - TURN OFF THE VAN ENGINE. Why waste gas?

Your generator is now running and you have full use of 110/120 volt generated power in your van. Simple. You use about 1/3 a gallon of gas in an hour. I am not sure how much propane the propane models use but I have heard that the propane generators are not as efficient as the gasoline generators are - and this seems to hold for generators in general (not specific to the Onan).

When you are ready to shut off the generator, first turn off all appliances using generator power - A/C, microwave, TV, etc. and then JUST PUSH THE BOTTOM OF THE GENERATOR SWITCH. The generator will come to a rumbling stop. If you don't need battery power for any reason, turn off the battery switch.

Simple, but the story does not end here, unfortunately. Having a generator means devoting time to it on a regular basis to keep it properly maintained and working so that it is always ready and working when you want it to be.

The generator must be "exercised" under load for two hours* every month. What this means is that you need to go out to your Roadtrek and start your generator and then put a load on it - half load is recommended which is either the air conditioner or the heat pump or a plug in electric heater - and leave it running for two hours. And you must do this every month. If you look in the Roadtrek manual it will talk about doing this for a half hour every month - BUT - the Onan manual says two hours and my dealer service told me that if there is a problem that requires warranty repair they have to tell Onan how many hours are on the meter - and if those hours don't at least show the exercise time for the age of the generator, they do not have to cover repairs under the warranty. But there is good reason to do this other than to make Onan happy. The generator really does need to be run this way. Some owners use the generator more exercising it this way than they do actually using it- me included.

The oil must be changed on the generator after the first 20 hours of use. After that the oil is changed after every 150 hours or at least once each year. See the manual for the type of oil to use. This varies by the outside temperature the generator is operated in. The most usual temperature range 10dF to 100dF should use 15W-40. Many change the oil themselves - it takes just one quart of oil. I have our dealer/service center change the oil. It is necessary to crawl under the Roadtrek to access the generator to do anything to it. This includes checking the oil and changing the oil and filter which should also be changed every 150 hours, There is a maintenance schedule in the manual. Here is a link if you don't have a manual.

You are supposed to check the oil every eight hours of use. This means crawl under, open the hatch on the generator and unscrew the oil cap and check the level. The van must be on level ground  (lots of luck). Unscrew the oil cap and pull out - the dipstick is attached. Wipe it off and then reinsert WITHOUT SCREWING IT IN. Pull out and read the level. If you need to add oil you must try to pour it in to that hole with a funnel or some other device. I found a pump that fits on the oil bottle and pumps the oil up into the hole through a hose. (I have not yet had to use it.)  IF THE OIL GOES BELOW HALF the generator will not operate. If you have a problem getting your generator to run or it just suddenly stops - CHECK THE OIL LEVEL.  You can find 15w-40 oil in Walmart or an auto store.

There is an adjustment to be made on the generator for high/low pressure changes - like going up into high mountains. See the manual about this. So far we have not been anywhere that would need this adjustment. 

Something else that is very important to know about your gasoline generator is that it cannot use Flex Fuel* so even though our Roadtrek can use Flex Fuel, we cannot put it in the tank because it would ruin the generator. The generator is fine with E10 ethanol. Some find it beneficial once a year to put a gasoline additive that will remove the clogging effects of ethanol on small engines into the van gas tank and run that treated gasoline through the generator. There are various gasoline additives that are available that will clean your engine and generator motor of ethanol deposits. There has been a discussion lately as to what is best and one product that several have used is under debate as to whether it does this properly or not. What you want to get is a gasoline additive specifically for ethanol treatment.  IF YOUR ROADTREK HAS A PROPANE GENERATOR YOU DO NOT DO THIS.

When you need the generator, all of this is well worth the effort - even though it often feels like a pain for the few time the generator is used. But when we needed the Roadtrek powered in a Blackout - the generator came to our aid! If considering buying a Roadtrek  - or any RV - you really do want a generator. The new ETrek Roadtrek has a completely different generator that runs off the van engine and will charge the batteries in a half hour. There are innovations coming!

 Here is a link to an excellent set of photos of the internals of the Onan Generator that is in our Roadtreks - Generator Photos 
Thanks to the site - Red Rover the Roadtrek.


*ADDENDUM:

Jim Hammill, President of Roadtrek, after reading this article suggested I add the following. Also, please note that my articles are not "Roadtrek Factory Authorized". They are based solely on my experience, observation, and learning from other Roadtrek and RV owners. 

1.Propane generator in Sprinter is a 2500 KW not 2800 KW. Gas Generator is 2800 KW. 
 
2.In many situations, the generator will run the microwave and the AC, and in many situations it will not. It depends on how hot it is outside, causing the AC compressor to draw more power, and how many other items are on in the van. 
 
3.The generator is not connected to the vans gas line. There is a special gas pickup tube installed on the GM gas tank, so the generator has its own fuel line.
 
4.We at Roadtrek guide consumers to run the generator under a small load for 45 minutes a month when using infrequently. 2 hours would be used when you don't do it every month. 2 hours is extreme and in our opinion, far more than needed for routine maintenance.**
 
5.Another option is to just run the generator out of fuel before you store it, by installing a fuel shutoff switch on the generator fuel line. of course, remember to turn it back on in the spring. 
 
6.There is no cut off switch that stops the generator from working when the tank reaches 1/4 full. The gas tank pick up tube is mounted higher than the vehicle pickup tube to ensure the generator runs out of gas first.
 
7.The generator is not connected to ALL the electric circuits in the unit, as it goes to the inverter/converter/charger, which simply charges the batteries, and creates 12 volt power. The batteries power the 12 volt circuit.
 
8. As a comment, just run mid grade gas or higher in your Roadtrek to avoid the E85 issue. Modern cars and trucks have fuel injectors that handle it. Carburetors on generators have small ports that gum up. This is not a big deal at all, and consumers should just use 87 octane or better.


**Because of how strongly my Roadtrek service center emphasized Onan's insistence that the generator be "exercised" for two hours each month or Onan can refuse to honor the warranty for any repairs, I will continue to run the generator each month under load for the two hours. This is something where Cummins-Onan and Roadtrek differ in opinion on and while I am sure Roadtrek has reason to feel that 45 minutes a month is sufficient, Onan is the company that the service center will have to go to for approval of any warranty work. Since I use my generator rarely when traveling, exercising it is the most use it gets.