How long can an engine sit dormant?

[gator67]

We've never stayed anywhere more than 31 days without moving the coach, because we arranged it that way. However, it appears that we will be staying where we are almost 8 weeks, and then in the spring, 12 weeks. How long is it safe to go without starting the coach and driving it a while? Is it best to go somewhere every month or so to warm up the engine and exercise the tires? What are your experiences with this?

[gator67]

We've never stayed anywhere more than 31 days without moving the coach, because we arranged it that way. However, it appears that we will be staying where we are almost 8 weeks, and then in the spring, 12 weeks. How long is it safe to go without starting the coach and driving it a while? Is it best to go somewhere every month or so to warm up the engine and exercise the tires? What are your experiences with this?

[Triangle Drifter]

You can leave a diesel a long long time. Look at all the equipment that sits in storage yards. I have a Cummins in my boat, The boat has been dry stored since August, LAST year. I try to run the engine every few weeks but for one reason or another the engine sat from March this year to just a few days ago. No trickle charge. Nothing till I turned on the charger last Friday. In 15 minutes the batterys were indicating full charge. I hit the starter. It was as if the piston was just about at the top of the compression stroke & was only running 1/2 hour ago. She fired right up.

Right now our Alpenlite is in storage. It won't be touched till next April. The batterys are disconnected. The trailer is jacked up so that most of the weight is off the tires. I've been doing this for the past 2 winters with no ill effect to batterys or tires.

[GaryKD]

Hi Jerry,
Millions of RV engines come to Florida and sit for 6 months or more, every year. For the times you are considering, I'd take this item and remove it from the list of things you need to worry about.

I'd worry more about the tires. Will they be covered? If on concrete, or ground (like dirt or grass) will the tires sit on a protective piece of plastic or some other inert material?

[gator67]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I'd worry more about the tires. Will they be covered? If on concrete, or ground (like dirt or grass) will the tires sit on a protective piece of plastic or some other inert material? </div></BLOCKQUOTE>

Thanks. I'm somewhat anal about that. If I am staying somewhere more than a week I always make sure the tires are on wood (if they need it for leveling) or plastic. And, I always cover them. I just put a couple of Michelin XZE2 tires on the front at $468 each... gonna take care of them!

[becks]

Is it also ok for a diesel to sit idle for six long months of a Minnesota winter? Or does it simply make no difference or do any harm whether warm or cold?

[Steve Rankin]

We started the engine on our DP when we needed to move the coach. If the coach didn't need to move, the engine remained off. That meant about 4 months during the winter. We did the same with our boat for 17 years, sometimes going 6 months to a year without running the engine. Just put some stabilizer in the fuel first.

[skp_member]

I would add one thing. Try and have the fuel tank full, as it will help prevent moisture accumulating, and if you are in a high humidity area, consider adding diesel bioside. It's available at most marine stores like Boat US, West Marine. Some auto parts stores. It will kill any growth of alge in the fuel.

We are in the Texas Hill country for winter and will sit for 2 months, then a 600 mile trip, sit for 3 months, then a 600 mile trip and sit most of the summer. All I'll do is have it full when we park.

Jim

[GaryKD]

Hi becks,
Go here and see which product will work best for you. This company has been in the diesel injector business a very long time.

I use the blue labeled product. Stanadyne Performance Formula. It works as advertised. I continue to buy and use the product.

[Algoma]

Like Gary I have been using Stanadyne Performance Formula for some while. I buy the case of 12x16oz bottles and add one to the tank every time I fill up, which is usually close to the 60 gallon mark.

I have always topped up my tank before the winter lay-up to reduce condensation but I have recently read that this doesn't make much difference.

[CJBROWN]

Yes, a diesel is easy to store. Gas goes bad without a stabilizer, from about 8 weeks on.

A good diesel additive is highly recommended as has been mentioned. Besides, they can all benefit from an additional lubricant as the ULSD has considerably less now. One of the best is FPPF, they have a bus and rv blend that's cheap and works great. Treats about a hundred gallons with one 16oz bottle. My duramax loves it, runs so quiet.

It is worse to start up a diesel and just idle it. You're better off not running it. When you start it plan to drive it somewhere, get it good and hot and burn off all the moisture in the crankcase and exhuast system.

Don't store it for long periods with old oil. Go with a recent oil change before storing for a long period. If you're in really cold and damp climate consider blocking the intake so less moisture gets in.

Taking the weight off tires it recommended, and keep them covered, not exposed to sun/UV.

[becks]

Gary KD.....Thanks for the tip. I was aware of the Standyne products, but had forgotten all about them. I think using them year round is probably money well spent.

[Old Rv'er]

Ok, here is how we do it.

Filled tank, added Stanadyne Fuel Conditioner.
We keep in a covered storage facility. I left the main circuit switches off. I fully charged batteries before putting away.

Drained fresh water tank and left open the valve. Left all low point drains open, and purged out the fresh water lines with low pressure air to clear them. All the water faucets, washer and dishwasher systems are open as well.

Added 1 gallon RV antifreeze to gray and black tanks to make sure they won’t freeze from waste which won’t drain and also added extra digester to black tank to hopefully eat up whatever is keeping tank from draining all the way.

Left batteries connected, but will plug in once a month to charge and check levels.

Tires on ground (gravel), but in shade, so not exposed to sunlight. All interior shades down so sunlight won’t get in to fade fabric/leathers.

Check about every two weeks, etc. Oil has about 3500 miles on it, so will have changed after first trip in spring along with me doing genset. I will also change air filter in spring as well.

Cannot think of anything else, but would have preferred to put RV antifreeze into plumbing system, but with APEX it’s difficult because Fresh water tank is main point of delivery.
Oh put in dry beads to absorb some moisture, but want a better solution.

[dgerstel]

Monty,

Try this, with an outside water source connected to the coach fill connection and on, set "auto fill" to off, turn off pump. Now see if you still have water available at faucets. If so then you have your main point of entry to add antifreeze into your system.

I was helping Lyle with finding where to install a check valve in the water system on his "06 Apex to eliminate a loop condition in the system. I found that his water system is what I would call unusual. I don't know if WRV changed this in later Apex's or not. WRV used two solenoid valves, one normally open, one normally closed, to create an electrically operated "three way valve." This is in place of the manual one for Water Tank Fill or City Water. When the Silver Leaf system auto fill is set to off or reached full, then the outside water source is always feeding the coach. (like city water setting on valve.)

My concern is for when staying in a RV park for a length of time with the city water left hooked up and the hose bib left on. Under these conditions if the auto fill setting is turned off or has reached full and the pump is on, city water will be mixed with RO water, depending on the city water pressure vs the pump pressure, and supplied to the coach faucets.

I am not sure what the Silver leaf does with the valves, I am assuming that they are powered at the same time.