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B Bob 09-22-2011 09:21 AM

What is hard about motor homes sitting for months at a time is

1. Very hard on tires to sit in same position for months.
2. Internal engine components can rust when oil not circulated for months.
3. Hoses can rot.
4. Seals like to be used.
5. Batteries like to be charged and used.
6. Mice and other creatures like to explore and build homes in motor homes sitting for long periods. This one esspecially has been a problem for me.

For sure my motor home takes about 3-4 days into a long trip before she seems to run the best.

Bob Affinity 42'

Journey 4 09-22-2011 09:45 AM

Somewhat stumped
 
Hello, I am in the process of purchasing a 2006 Mountain Aire. (13,000 miles). We were also interested in a 2008 AC Tradition which was $70,000 more. Get a call late last night and they came down $50,000. Any thoughts between the two coaches; better purchase for maintenance, quality of construction etc.
Thank you.

Mekanic 09-22-2011 10:01 AM

Quote:

Originally Posted by mikron (Post 962433)
Been looking at DPs on ebay and notice most diesels for sale that are 4 to 8 years old have less then 20,000 miles on them. I was told by more then one diesel repair shop that is bad for a diesel. Average use should be 15,000 or more each year. So to all the DP owners whats up.

Short trips are bad but only IF your engine oil and coolant do not get up to operating temp for about 30 min.
My 1994 Ford diesel I bought had only 107K on it when I bought it last fall. For a truck of that age that is also low miles.
It had sat for a couple of years.
All fluids and filters got changed as well as the fan belt. that and some new tires and it drives and runs like new.

Pairajays 09-22-2011 12:10 PM

Quote:

Originally Posted by B Bob (Post 964949)
What is hard about motor homes sitting for months at a time is

1. Very hard on tires to sit in same position for months.
2. Internal engine components can rust when oil not circulated for months.
3. Hoses can rot.
4. Seals like to be used.
5. Batteries like to be charged and used.
6. Mice and other creatures like to explore and build homes in motor homes sitting for long periods. This one esspecially has been a problem for me.

For sure my motor home takes about 3-4 days into a long trip before she seems to run the best.

Bob Affinity 42'

Well, let's see. Tires sitting for long periods can result in flat spots. I've never had a problem with flat spots on my tires when properly inflated. Deploying leveling jacks could solve that. Rusting engine components. i just don't understand that. Oil does not evaporate, if it was oily when you shut down, it's going to be oily when you start up. Even parked in high humidity areas, I doubt enough moisture could get to your engine components that would cause rusting. What causes hoses to rot when parked and not when running? I don't know what seals you are talking about. I know some seals stop doing the job, but it takes more than 5 or 6 months for this to happen. I don't understand what you mean when you say batteries like to be charged and used. Most, if not all, MHs have charging systems to keep them charged while parked. What harm will result if a battery is not used? I do agree you might have a mice problem unless your RV is well insulated against them.

What about farm equipment? They sometimes sit idle for 8 or 9 months. Do all the things you sited happen to them? What about new or used MHs sitting on dealer lots for months? I'm not implying i'm an expert on this subject, just going by my experience and using common sense as I see it. It is not unusual for folks to pass along information given to them by others with no details provided. An example would be someone, living in a New England state, leaving their RV parked uncovered during the winter months. I don't doubt the might have problems come summer.


Jim E

Full.Monte 09-22-2011 11:26 PM

Quote:

Originally Posted by Pairajays (Post 965075)
Well, let's see. Tires sitting for long periods can result in flat spots. I've never had a problem with flat spots on my tires when properly inflated. Deploying leveling jacks could solve that. Rusting engine components. i just don't understand that. Oil does not evaporate, if it was oily when you shut down, it's going to be oily when you start up. Even parked in high humidity areas, I doubt enough moisture could get to your engine components that would cause rusting. What causes hoses to rot when parked and not when running? I don't know what seals you are talking about. I know some seals stop doing the job, but it takes more than 5 or 6 months for this to happen. I don't understand what you mean when you say batteries like to be charged and used. Most, if not all, MHs have charging systems to keep them charged while parked. What harm will result if a battery is not used? I do agree you might have a mice problem unless your RV is well insulated against them.

What about farm equipment? They sometimes sit idle for 8 or 9 months. Do all the things you sited happen to them? What about new or used MHs sitting on dealer lots for months? I'm not implying i'm an expert on this subject, just going by my experience and using common sense as I see it. It is not unusual for folks to pass along information given to them by others with no details provided. An example would be someone, living in a New England state, leaving their RV parked uncovered during the winter months. I don't doubt the might have problems come summer.


Jim E

Jim,
You are lucky to live in a low humidity area. It helps you avoid some of the problems discussed. I own 3 vehicles with diesels. The problem with
leaving engine oil for long periods in an engine in non-operating status is that it collects water. Where does the water come from? It comes from the air that is above your engine sump. When the temperature drops from high to low during the 24 hour cycle, any moisture in the air condenses on the cold motor parts and exposed oil pan surfaces. It's the same phenomenon that makes your grass appear damp in the morning even though you haven't run the sprinklers. The water droplets thus formed slide down into the oil sump. Water, being heavier than oil, collects in the bottom of the sump and starts rusting your oil pan. I rusted out an oil pan from the inside this way once. Pin holes open up and the pan starts leaking. When you operate the engine frequently, the water gets heated up and comes out of the tailpipe as steam, reducing the amount of water in the sump and the damage it causes. That's why they recommend oil changes based on number of miles driven (because of oil lubrication breakdown) OR number of months (because of water contamination), whichever comes first.

You are also incorrect about battery maintenance, but that's a whole different subject.

Pairajays 09-23-2011 10:08 AM

Quote:

Originally Posted by Full.Monte (Post 965552)
Jim,
You are lucky to live in a low humidity area. It helps you avoid some of the problems discussed. I own 3 vehicles with diesels. The problem with
leaving engine oil for long periods in an engine in non-operating status is that it collects water. Where does the water come from? It comes from the air that is above your engine sump. When the temperature drops from high to low during the 24 hour cycle, any moisture in the air condenses on the cold motor parts and exposed oil pan surfaces. It's the same phenomenon that makes your grass appear damp in the morning even though you haven't run the sprinklers. The water droplets thus formed slide down into the oil sump. Water, being heavier than oil, collects in the bottom of the sump and starts rusting your oil pan. I rusted out an oil pan from the inside this way once. Pin holes open up and the pan starts leaking. When you operate the engine frequently, the water gets heated up and comes out of the tailpipe as steam, reducing the amount of water in the sump and the damage it causes. That's why they recommend oil changes based on number of miles driven (because of oil lubrication breakdown) OR number of months (because of water contamination), whichever comes first.

You are also incorrect about battery maintenance, but that's a whole different subject.

I understand the humidity and condensations process. The engine and associated oil sump are a sealed unit. I doubt any outside air can get inside the sump. The humidity of the air that is initially inside the sump would therefore remain constant because it is never exchanged.

Jim E

mikron 09-23-2011 10:22 AM

I am reading all the replys and find most think sitting not good. Living in Florida we can travle year round mostley (90%) in Florida unit always working. I get from the replys do maintenance as required no mater miles travled and I should be ok. I run my gas unit and always have every 30 to 45 days for 30 miles or so and change the oil every 6 months. With a DP it looks like I don't have to change the oil that often.

HD4Mark 09-23-2011 03:09 PM

Quote:

Originally Posted by mikron (Post 965828)
I run my gas unit and always have every 30 to 45 days for 30 miles or so and change the oil every 6 months. With a DP it looks like I don't have to change the oil that often.

Yes but your gas unit will take 7 quarts max for a 6 month change while a DP can go 10,000 the one year change period will use 3 times as many quarts and a much more expensive filter. So even though the diesel can go further and longer it is no cheaper.

mikron 09-23-2011 03:29 PM

I did understand that, but not much more for the diesel for the better ride and steady power is ok by us. I don't hate my gas coach just reading all the postings and replys how the deisel rides and handles better. Will have to up grade my lic. so I can test drive a diesel.

mikron 09-24-2011 06:56 AM

Quote:

Originally Posted by mikron (Post 966055)
I did understand that, but not much more for the diesel for the better ride and steady power is ok by us. I don't hate my gas coach just reading all the postings and replys how the deisel rides and handles better. Will have to up grade my lic. so I can test drive a diesel.

Checked Florida Lic. law, don't need any different class Lic. from driving a car (class E) up to a 45' rig for RVs only. Scarry, I feel ok drove heavy equipment trucking in service including Fargo & Brill busses.

Full.Monte 09-25-2011 07:41 AM

Quote:

Originally Posted by Pairajays (Post 965809)
I understand the humidity and condensations process. The engine and associated oil sump are a sealed unit. I doubt any outside air can get inside the sump. The humidity of the air that is initially inside the sump would therefore remain constant because it is never exchanged.

Jim E

Jim,

This is from Wikipedia:

Air ventilation

Main article: crankcase ventilation system
During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by".[7] If these gases had no controlled escape mechanism, the gasketed joints would leak (as they "found their own way out"); also, if the gases remained in the crankcase and condensed, the oil would become diluted and chemically degraded over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust.[8] To counter this, a crankcase ventilation system exists. In all modern vehicles, this consists of a channel to expel the gases out of the crankcase, through an oil-separating baffle, to the PCV valve, into the intake manifold. In a non-turbo engine, the intake manifold is at a lower pressure than the crankcase, providing the suction to keep the ventilation system going. A turbo engine usually has a check valve somewhere in the tubing to avoid pressurizing the crankcase when the turbo produces boost.
If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced.[7] Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick,[9] or out the PCV valve. In rare cases of serious piston or ring damage, the oil filter housing's sheet metal can even burst at its seam.
------------------------------------------------



So, the crankcase is not sealed. Therefore, condensation inside the crankcase can deposit water into the oil and start corroding the oil pan.
If you've ever seen an old car or truck sitting out in a farmer's field for a number of years, you might successfully wager that rust has formed in a lot of places inside the engine due to humidity and temperature changes, not just in the crankcase. That's why engines thus "stored" are often seized and unable to rotate.

Pairajays 09-25-2011 08:59 AM

Quote:

Originally Posted by Full.Monte (Post 967168)
Jim,

This is from Wikipedia:

Air ventilation

Main article: crankcase ventilation system
During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by".[7] If these gases had no controlled escape mechanism, the gasketed joints would leak (as they "found their own way out"); also, if the gases remained in the crankcase and condensed, the oil would become diluted and chemically degraded over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust.[8] To counter this, a crankcase ventilation system exists. In all modern vehicles, this consists of a channel to expel the gases out of the crankcase, through an oil-separating baffle, to the PCV valve, into the intake manifold. In a non-turbo engine, the intake manifold is at a lower pressure than the crankcase, providing the suction to keep the ventilation system going. A turbo engine usually has a check valve somewhere in the tubing to avoid pressurizing the crankcase when the turbo produces boost.
If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced.[7] Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick,[9] or out the PCV valve. In rare cases of serious piston or ring damage, the oil filter housing's sheet metal can even burst at its seam.
------------------------------------------------



So, the crankcase is not sealed. Therefore, condensation inside the crankcase can deposit water into the oil and start corroding the oil pan.
If you've ever seen an old car or truck sitting out in a farmer's field for a number of years, you might successfully wager that rust has formed in a lot of places inside the engine due to humidity and temperature changes, not just in the crankcase. That's why engines thus "stored" are often seized and unable to rotate.

The Wikipedia article is referring to an engine that is running, not stopped. Very little, if any, air exchange can take place through the crank case ventilation system when the engine is not running. "Old" cars and trucks had a much different ventilation system. I agree that internal engine components can get rusty after sitting for "years" but I don't think it is going to happen in 5 or 6 months, which is what this thread is about.

Jim E

Poptop 09-25-2011 08:20 PM

The odds of finding many motorhomes that have been driven 15,000 miles a year are better that me winning the lottery, but not very much better. The MH that has had religionous maintenance is probably going to be a safer bet. Having said that when reading the comments posted here consider your risk tolenance. Some people wear suspenders with belts to be safe, others are willing to be more adventureous. If the scheduled maintenance is specified to be three years and it doesn't get done until four years or so it probably won't be an issue unless you have a claim you want covered under warranty.

HD4Mark 09-26-2011 07:28 AM

Let's face it, anytime you purchase something pre-owned, commonly known as used, it is a crap shoot. High miles means the engine got lots of use. Might be better for the engine but perhaps not for everything else. Our '04 is the first used vehicle I have owned in about 30 years. Made me nervous but other than a few fixable problems it has worked out fine.

I will say that even if we may have paid a little more buying from an RV dealer, we were treated very well. A couple of problems with it were taken care of no questions asked. We were also able to trade in the old MH. Again we may have been able to get more for it or save some money with a "clean deal" but it not only saved the problems with selling it but saved 8.25% tax on the trade in amount that was taken off the purchase price. Just some of the differences between a dealer and private sale.

The dealer was Colton RV in Buffalo NY if anyone is interested. YMMV


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