Onan Propane Instead Of Gas.........

MaxOwner

Active Member
Hey all.

We are spening the money to get an Onan installed into our Landmark Key Largo.

Due to not being able to find a gas tank that I feel "safe" with, we are getting a propane Onan installed. Not happy about this but the fuel supply should work.

The propane generator has a 6500 watt rating instead of 7,000.

Is there anything I need to know about propane?

After reading in another post, I am springing for 2 separate tanks to be installed beside gen set and tied into the generator exclusivley.
 

Urban350

Well-known member
You will be happy with the gen, other then the propane as it burns cleaner and you never have to worry about bad fuel or with running your generator once a month like you should with a gas one. Also no fuel filter.
 

lwmcguir

Well-known member
We have ran the off road ranch flat beds for years on straight propane. Years ago we had the conversion kits. No problems at all with our propane generators or trucks. Just a little bit unhandy to re-fill. Since there are less BTU's per gallon you will burn more and that is the only drawback we have ever ran into. Oil stays cleaner so oil changes are 300 hours/annually on our equipment just because. You could go 500 hours or annually easily on oil changes for normal operation.
 

danemayer

Well-known member
You might want to review the "Average Fuel Consumption" at different loads. It's expressed in gallons/hour and may range from .5 to 1.2 gal/hr. A 40# propane tank holds about 9 gallons. The spec sheet links are on this page.
 

MaxOwner

Active Member
I was thinking about using 2x 40 pounders untill I took one out from the trailer supply and stuck it in the front storage cabinet. Was awkward getting it in and out without the generator in there.

Turns out the propane gen will be 4 weeks getting here. I am now leaning towards the gas gen again. Going to contact Heartland and see if they can get a proper fuel tank and I guess a base for the generator.

For some reason I am stuck on a gas generator.
 

danemayer

Well-known member
Fuel choice might come down to how you plan to use the generator.

We use the 2 x 40# LP tanks that are standard on the rig to power the generator. Mostly it's for backup when there's a power outage. Last winter the town we were in lost power for about 6 hours. I think temps were in the 10-20 degree range, and the genny let us run the furnace without running down the batteries. Probably used a bit less than 1/2 a tank.

For that type of intermittent use, I think LP is probably the first choice. No worries about stale fuel or gummed up fuel lines, etc. Even when using the LP tanks to run the furnace, there's enough to spare for the generator.

If we were using it for boondocking on a regular basis, I might prefer gas since propane might not be available near the boondocking site, whereas gas is more likely to be available.
 

TomMar

Retired Texas-South Chapter Leader
Fuel choice might come down to how you plan to use the generator.

We use the 2 x 40# LP tanks that are standard on the rig to power the generator. Mostly it's for backup when there's a power outage. Last winter the town we were in lost power for about 6 hours. I think temps were in the 10-20 degree range, and the genny let us run the furnace without running down the batteries. Probably used a bit less than 1/2 a tank.

For that type of intermittent use, I think LP is probably the first choice. No worries about stale fuel or gummed up fuel lines, etc. Even when using the LP tanks to run the furnace, there's enough to spare for the generator.

If we were using it for boondocking on a regular basis, I might prefer gas since propane might not be available near the boondocking site, whereas gas is more likely to be available.

I agree with danemayer. The positives of using propane out weigh the negatives. With the two 40# bottles already on the KL you should have plenty to share with the generator. If it becomes necessary for extra propane I would strap an extra 40# bottle in the bed of the truck and swap it out when I had to switch tanks. - JMO
 

MaxOwner

Active Member
Ugh! Not sure which way to go.

Looking at the fuel consumption rates, we would get a little less than 9 hours on a tank of propane.

Thanx for the replies, guys. Gotta stew about this.
 

danemayer

Well-known member
we would get a little less than 9 hours on a tank of propane.
If you're running 2 air conditioners, microwave, coffee pot, fireplace, TV and a hairdryer all at the same time, maybe 9 hours. We've run 12 hours on a bit less than 1 tank with one A/C running the whole time.

Gas consumption is only slightly less than LP. So if 18 gallons of LP isn't enough for what you plan to do, you'll need to figure out how to carry enough gas - 30 or 40 gallons perhaps? That's a pretty big tank. I don't know where it would fit our Rushmore.
Maybe the truck bed? But then you'd always have to have the truck next to the rig to use the genny. Basement? But then you'd give up most of your storage area.

Tradeoffs are difficult, but I think it comes down to how much you plan to use the generator and in what circumstances.
 

ZNK

Well-known member
I think it is important to consider how much gas prices are fluctuating as well...unless this is a diesel generator. Propane in my neck of the woods is MUCH cheaper than gas.
 

gasman

Camp Socializer
According to an Onan service tech, it is necessary to install a fuel filter on LP units. The filter's job is to remove the oil that is in the propane. Your appliances simply burn off the oil but with the genny, the oil will compromise the injector nozzles. Also the LP gen sets are a little bit noisier than the gasoline breed.
 

porthole

Retired
Too bad you can't just install a Cyclone fuel tank, they hold about 25 gallons. That gallonage offers a good amount of run time.
 

MaxOwner

Active Member
Hoping Heartland will get back to me a bout a gas tank that can mount beside the generator in the front cabinet.

Thanx guys.

Plan B will be a propane Onan.
 

danemayer

Well-known member
Hoping Heartland will get back to me a bout a gas tank that can mount beside the generator in the front cabinet.
Looks like you've already covered this in your other thread.
 

MaxOwner

Active Member
As an update, the trailer has been in for 2 weeks (taken allot longer than told.....) and we had a 6500 watt LP Onan installed.

We found out that we got a bum transfer switch so it will be another few days.

What do I need to know about this thing? Looked on the Onan site at the owners manual. But it is different from the actual generator installed in the trailer. We get the trailer (with the paper manual) back Thursday and we hit the road Friday morning.
 

RollingHome

Well-known member
Since you have a brand new Onan you only have to do the basic checks (oil, leaks, etc.) the dealer should cover these with you when you take delivery. Then of course, scheduled proper maintenance as Onan dictates. I hope your Onan has an hour meter, if not, have one installed ASAP. Keep a log book for warranty and memory issues. You may want to find a local COMPETANT Onan certified (or not) technician for when/if you have repair needs – before – the needs arise. You could ask boaters in your area who they use for their Onans.

Happy RVing !
 

danemayer

Well-known member
Maxowner,

Oil change once a year whether you've run it a lot or a little. I think you want to "exercise" it periodically - run for an hour each month.

Be aware that the generator may be the most demanding on LP feed being correct. It LP hoses or regulators aren't delivering 11 water column inches of pressure, failures will likely show up on the genny first where it shuts down with an error code. LP pressure may not show up as a problem when tanks are full - only after they get down to 1/2 full.

Also be aware that starting it depends on having a battery charge. The catch 22 is that while you can charge the battery by running the genny, you have to have enough charge on the battery to start the genny. If not, you can probably charge up the battery from your truck in 20-30 minutes at a high idle.
 

MaxOwner

Active Member
Thanx guys.

Sounds like the information from the online manual is good. But the drawings are different then what I saw first hand on our generator.

We have 2 separate tanks installed in the front cabinet. If this becomes a hassle, will re route the hoses to the trailer propane supply.

Pressure supply.....? Hope we got this right. We had a place that deals with industrial generator installs and repairs. But the local RV dealerships use these guys to do installs for customers of new bought trailers.

Will try and post a picture when I get the trailer back. Maybe tomorrow if things go well......
 
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