Why you should run your DP periodically in storage.

[Cooperhawk]

Our DP has been in storage since Oct. It's stored in an unheated building and all I've been doing is starting and running the genset once a month. Yesterday I started it up to take it to a shop for routine maintenance and had a problem.

The engine heater was plugged in and she fired right up, however, I could not get the air bags to inflate nor could I get enough air pressure in the front tank to release the brakes. The reason was there was ice in the lines.

Our Winter has been one of those where one day it's 35 degrees, and the next below zero. I'm guessing that all that heating and cooling put condensation in the lines, and because I wasn't running the engine, it built up and froze blocking air ports. If I had run the engine once a month the dryer should have eliminated it.

I finally got it thawed out by starting it, warming it up, and shutting it off to let the heat radiate through the system. About three in the afternoon I finally said enough and called the shop and told them I wouldn't be coming after all. Of course I tried it one more time, and Lo and Behold, it aired up.

From now on I will start it once a month just to keep it dried out.

Let the wisdom begin.

[twinboat]

The water ( moisture ) was already past the air dryer if it blocked the lines. The system is sealed from the atmosphere, while sitting.

The air dryer is the first thing the air goes thru after the compressor.

You need to have the air dryer serviced and drain your tanks of any water.

[Cooperhawk]

Well first they have to be thawed out.

[Cooperhawk]

Originally Posted by twinboat

The system is sealed from the atmosphere, while sitting.

Not sealed from condensation however.

[Grower15]

Not sure what chassis you have, but our chassis is a Spartan and they recommend moving the coach once a month (25’ forward and backwards) to keep the wheel bearings lubricated.

[twinboat]

Originally Posted by Cooperhawk

Not sealed from condensation however.

How is that ?

The only way outside air can get in the tanks is thru the compressor inlet then thru the air dryer and past a few check valves. There is no vent like gas and fuel tanks.

[Chargerman]

Starting the coach once a month without driving it to bring everything up to full operating temp is not a good thing to go. Getting things luke warm then shutting down causes condensation to accumulate in the engine and trans. I agree with the statement that condensation cannot accumulate in the air system if the dryer is functioning properly and the tanks have been drained occasionally

[Crasher]

We used to park our bulk farm trucks from Oct till April or May without starting them. Never found it to be a problem. Don't know why a motorhome would be any different. It's still just a diesel engine, transmission, air bags, and tires sitting on a steel frame.

edit: Preventative maintenance such as using an airline/antifreeze product would take care of any potential air system freeze ups.

[lonfu]

Lets put you in a cold room for 3 months and see how fast you are moving when you get up....

Newmar's are not really set up for cold weather. Inside storage or not, the more I work on repairing my barn find the more I realize this. 7 years sitting in storage has not been kind to this one....

Ok, so I also have the block heater. Exactly what is this? Is the heating element in the fuel tank to turn the diesel back to liguid when it gels or is it in the oil pan or is it actually in the block as the little sticker says? Looks like it runs off 110v so you must be plugged in to shore power for it to work? I can't seem to find any info on this.

this is a little off subject, I have leaking threaded air fittings at the bags, clearly the teflon tape is failing. Clearly the white teflon tape was not designed to handle the pressure and heat for this location. Any suggestions?

[Mac99]

The advice from the OP is not correct, based on everything I
have been told by Cummins, Allison, Freightliner and my
local shop that does all my work. Post #7 is completely
correct. Posts 2,6,8 are spot on as well. The OP has a
failed air dryer, and this raises questions for his air brake
system as well !

[BRex45]

I changed the title to what it should read.

[OLYLEN]

Have you purged the air system(drained the water out)? Have you serviced the Air Dryer at least every three years. Others above are correct Compressing air introduces water into the system, next stop is the air dryer, gets most of the water out. Then the storage tanks where again water can condense(on most RV's if the dryer is serviced no water). Starting you DP and not driving 30-60 minutes will not get the trans or coolant to operating temp. Idling a diesel does not even get near warm and can wash the cylinders.

LEN

[ElvistheKing]

Originally Posted by BRex45

I changed the title to what it should read.

Guess it depends if your definition of "run" includes a 1/2 hour drive or not ;-)

[JFXG]

Originally Posted by Cooperhawk

..... From now on I will start it once a month just to keep it dried out.

Let the wisdom begin.

Jim...
I don't know if monthly starts are necessary, but here's another reason for periodic starts.

(NOTE: readers, please don't rehash the old "don't start it without driving it" debate. I'm talking about specific circumstances.)

Jim, I note that you have an '02 vintage Cat 3126. Same as I have. That means your fuel system also includes a HEUI pump, a marvelous little piece of engineering that also (because of the way it operates) happens to be very sensitive to clean engine oil.

I've parked many times for 2-4 months with no problems at all, but once I parked for 5-1/2 months and my HEUI became very unhappy. Long story short, it all worked itself out, but it could have-- and damn near did-- cost me $4G to replace it.

This drove me to do some research and learn a bit about these little beasties. Now I start it after a couple months or so.