How Often to Exercise Engine?

[Jwl_Atlanta]

We are out of town this winter 4-weeks per location. How often should we run the the diesel to make sure it is ready to go when it sits for 4-weeks at a time? Thoughts?

 

[BGMAC]

When any engine sits for a length of time there are at least 3 things to consider.
1. Humidity. Engines do circulate air in the oil system. As the engine cools from running any moisture in the air condenses and this water all be it so small rest on exposed internal components. Now these components usually will have oil on them until The engine sits for a period of time where it will eventually drain into the oil pan. After that corrosion could occur. This could cause part failure or oil contamination.

2. Unnecessary bearing wear. As stated above over time all the oil will drain into the oil pan Leaving the bearing dry. Starting the engine the next time the bearings would be metal to metal for a short period of time causing a bit of wear.

3. Corrosion/ dryness of cylinder walls for the same reason stated above. This could cause excessive piston ring wear reducing combustion or smoke out of the exhaust.

Now motor homes sit for long periods of time. The one thing I would recommend and do is put an oil additive in that “clings” itself to parts or use a synthetic/synthetic blend of oil. Now I’m not talking about the old STP type additives that looks like honey when going in. I’m talking about something like Slick 50 where there formulated to adhere to parts without gumming things up. I combat this very same issue with my aircraft engine using a synthetic blend oil and an additive called AVBlend which is a “Slick 50” type additive approved for aircraft.

i also use Marvel Mystery Oil periodically to remove any varnish in the system.

One more thing and I am taking it from the aircraft side of the house. If the engine is not used for 4-6 months the oil should be changed.

So use additives, change oil on schedule or earlier, and exercise the engine as often as you can Running up to operation temperatures before shutting down.

Sorry for the long post, but for these same reasons I lost an engine on my first plane that I bought not knowing it sat for so long without being used. The engine blew up in flight.

 

[lostinfla]

Good writeup BGMAC. Glad to see you made it out of the plane ok. I usually run our coach at least every month, and since I have flooded batteries, I top them off at the same time.

 

[TJ&LadyDi]

Ours goes to the gym about once a month. Uhhh...well...at least, it gets started and run for a few minutes monthly. Same with the generator.

TJ

 

[Jim]

The engine blew up in flight.

Pretty impressive landing if you ask me.

 

[RKins]

Most of you are seasoned diesel owners and know that you don't and shouldn't just start the engine once a month. It won't get up to normal temp just sitting. When you start it, you should drive it around and allow it to get up to temp to get rid of the moisture you just created by starting it. You don't have to start them. Let them sit and make sure you maintain the batteries.
It is true that the genny manual states that it should be run once a month under load.

 

[BGMAC]

Most of you are seasoned diesel owners and know that you don't and shouldn't just start the engine once a month. It won't get up to normal temp just sitting. When you start it, you should drive it around and allow it to get up to temp to get rid of the moisture you just created by starting it. You don't have to start them. Let them sit and make sure you maintain the batteries.
It is true that the genny manual states that it should be run once a month under load.

Sorry, but you can’t create moisture by starting an engine. What you are doing is taking condense water that is in the engine and warming it up to create water vapor. Then you need to keep the engine running long enough and hot enough to expel the vapor out the breather.

As stated above if you have an additive that coats the interior of the engine will help prevent damage from water, but does not eliminate it.

If you really wanted to be pro active there are air drying devices for engines, and a couple of dyi ways of keeping things dry.