Chilling Thoughts: AC usage - Dash versus Generator

[Nonnaof Two]

Good thinking, we did this a year ago and it works great. However instead of a tension rod we tuck two panel long curtains in the overhead bunk. It’s easy to get to the fridge or whatever...

[TallPaul]

Originally Posted by MN_Traveler

Just looking at the numbers, it has been surprising how often I concluded that if I relied on just the genny and rooftop AC I would max out that 150 hour limit and need to find a place along the way to get the genny oil changed (a pain, and time delay I have sought to avoid).

Why not try a high end, long life oil, such as Amsoil Signature Series synthetic? Should be able to extend the oil change interval significantly and avoid roadside changes.

[powerboatr]

i cant recall ever just running the dash ac to be cool....nope never.
maybe the heat,




we almost 99% of time run genny, both roof a/c units and dash ac...
i plan for 7 mpg and adjust fuel stops accordingly
i like to be cool as a cucumber driving, and have even been known to aim the vent at the seat area...


i like my hotel room on wheels to be chillin

[10EC]

Originally Posted by mn_traveler

funny ... Strange as it sounds, i did mot consider changing the oil myself (have not done it yet so did not consider that it is relatively straightforward). The thing that occurs to me is that i would guess most campgrounds would not appreciate your doing so on site. So ... Where do you pull in and stop to execute that change?

t/a truck stops do lot oil changes.
Napa / auto zone ask em who would be a good ole boy with garage to help you change oil & give him $ to supply drain pan plus dispose of used oil for you. Just a thought.
My gen oil runs at bout 285 deg f at 85/90 amb, oil starts to break down at bout 300f i would watch that more so that hrs.

[JimPeoria]

Many of the newer coaches specially the diesel pushers have diesel gen sets also. Mine was a 3 cylinder Kabota turning an onan gen set. Would run all day on a quart of diesel. We changed out fridge to a residential 110 Volt unit after the Nocold failed the second time so needed to have 110 volts available to keep the fridge cold. We would run the gen set after about an hour or so of driving and if hot would keep in on to run the heat pump. Not many coaches use heat pumps now days but our 2005 Winnabago Vectra did and if it was 100 outside the air inside was 80 as it was only capable of lowering the air temperature 20 degrees. I changed the oil in the gen set at the same time I changed the oil in the 400 hp Cummins which seemed to work out to be about 150 - 200 hrs on the gen set and 6000 miles on the coach. Always felt like I had to rob a bank to do an oil and filter change on that beast.

[Papaslick]

We have a different situation in that our dash A/C doesn’t work and the repair costs are extremely high, therefore we depend solely on the genset for roof a/c. We changed to AMSOIL synthetic and have tested the oil at 250 hours to find that it still retained 60% life. I now change air and fuel every 250 hours and oil and filter every 400 to 500 hours with excellent results. We have a 10K Onan Quiet Diesel genset. Air and oil changes are a breeze, fuel filter is a pain. Looking to relocate and change the fitment on the fuel filter.

[geordi]

Originally Posted by Papaslick

We have a different situation in that our dash A/C doesn’t work and the repair costs are extremely high, therefore we depend solely on the genset for roof a/c. We changed to AMSOIL synthetic and have tested the oil at 250 hours to find that it still retained 60% life. I now change air and fuel every 250 hours and oil and filter every 400 to 500 hours with excellent results. We have a 10K Onan Quiet Diesel genset. Air and oil changes are a breeze, fuel filter is a pain. Looking to relocate and change the fitment on the fuel filter.

Depending on the space you have up front, it should be quite easy to do what I did for the fuel filter. I have an Onan QD7500 on mine, and while I disagree that the oil filter is a "breeze" (it always seems to weld itself into place!) the dumb design for the fuel filter isn't too hard to fix.

You will need a fuel filter head to match your desired filters, since I'm looking for easy supply I chose the Luber-Finer filters that are available at truck stops. Those fit the filter heads like this:

https://www.amazon.com/dp/B000CSGT64...v_ov_lig_dp_it

Mount it to something solid in a convenient location and using the 1/2" NPT ports and nipples, I ran goodyear fuel rated 3/8" line under the generator and to the fuel filter door. I removed the fuel filter door - it just unscrews - and cut off the end of the hard tube from the fuel pump. This is (luckily) a pressurized fuel system, just shove the 3/8" line over that hard tube at least 1.5 inches and use 2 hose clamps for security. The other side is flexible, cut off the fitting and use a 3/8 double nipple and clamps... And you are done!

I would highly suggest pre-filling the filter with Diesel Kleen and then holding the prime switch for at least 10 seconds to try and purge the air. Even doing that, I still had it stumble on me a couple times, but after about 5 minutes idling with the breaker off, it has been great ever since.

[rcnuts]

Originally Posted by computerguy

Sounds like way too much thought being put into this. If changing the oil is a concern don't run the genset.
It takes all of 30 minutes to change mine. If 30 minutes across 150 hours of use is a problem please don't drive near me.
Life is way too short to sweat the small stuff.

I agree with this. My solution with our 93 Holiday Rambler was to replace the motor ac compressor with a larger unit. There was a significant increase in the EFFECTIVENESS of the cooling after that. Milage vs running the genny? Im sure Ill never know. When it gets very hot outside you bet we'll run the roof air. So far only had to do that a few times but would fire up the genny without hesitation before being uncomfortable. This subject has been over evaluated IMHO.
Harris

[frankmaps]

that is the most important fact, keeping the whole interior cool. you wouldn't cool just your living room in a house because you're not in the rest of it.

[Funding Fun]

I would run generator and roof top if needed but my dash unit keeps coach very comfortable. The overhead cap keeps sunlight off of the truck cab and windows so I don't have those issues. Depends on insulation upfront, how close you are sitting to your engine and how big of a fish bowl you drive in.

[MN_Traveler]

Originally Posted by computerguy

Sounds like way too much thought being put into this. If changing the oil is a concern don't run the genset.
It takes all of 30 minutes to change mine. If 30 minutes across 150 hours of use is a problem please don't drive near me.
Life is way too short to sweat the small stuff.

I have debated for a while whether to respond to this - and have obviously decided to do so.... Not all of us use our rigs the same way. Some have a lot of clock time available, some do not. In my case, my question was prompted by several cross-country trips defined by limited calendar days to make my miles, and the need to boondock frequently (Flying J, Walmart...). Across the south, that frequently means running the genny at night to power the AC. Doing the math, I could easily have exceeded the 150 hr run-time limit on my genny running it day and night. The location and limited time of my overnight stops, and limited calendar days made it difficult to find and "drop in" for an oil change somewhere. This does not translate into bad or dangerous driving - just limited available time. Please be nice: I think the question and ensuing discussion is reasonable.

I appreciate many of the comments made here - especially the awareness that a DIY genny oil change can be quicker than I might have thought. I still have concerns, with a quick-travel schedule, with where to do the change and how to dispose of the used oil while on the road, but I am sure these can be addressed.

[MN_Traveler]

Originally Posted by geordi

Color me confused... Jack stands? Under a diesel pusher?


1/2" full-port ball valve, threaded. (non full port is OK, b/c the hole is still usually about the same as the drain port)
1/2" MPT to 3/8" barb nipple - This will be the actual drain port now, you can add tubing if you want to make it super clean into your container.
1/2" MPT to 3/8" FPT threaded bushing
3/8" x 1.5 pipe nipple.
On the chance that your plug is smaller (mine was) also get these:
1/2" MPT to 1/4" FPT threaded bushing
1/4" x 1.5 pipe nipple

Geordi - I am intrigued. two questions, but first a comment:

Quite a number of previous threads re. doing under-carriage maintenance on a DP have raised the concern regarding unexpected failure of either or both of the air bags and hydraulic levelers while you are underneath the rig. The probability might be small - but the downside, if it occurs, is big. Roll your dice. I do occasionally get under the front of the rig, but only where there are spaces tall enough for me to survive should the thing suddenly drop.

I am intrigued by your plumbing suggestion. I get the general idea, but am confused about how the pieces would be connected (sorry if I am just being stupid). Can you please clarify either with a diagram or using words?

Question: my first thought is :what if the valve opens up on its own due to road vibration while driving? Do you have any concern/experience with that - or is there something you do to secure the valve in the closed position?

[pobstlmo]

My Winnebago Coach is built on a Freightliner truck chassis, I noticed the other day when the dash was apart that the only thing separating me from the front outside is a Single Metal Plate, No Insulation, therefore I insulated as much of that single metal plate as possible.

[geordi]

Originally Posted by MN_Traveler

Geordi - I am intrigued. two questions, but first a comment:

Quite a number of previous threads re. doing under-carriage maintenance on a DP have raised the concern regarding unexpected failure of either or both of the air bags and hydraulic levelers while you are underneath the rig. The probability might be small - but the downside, if it occurs, is big. Roll your dice. I do occasionally get under the front of the rig, but only where there are spaces tall enough for me to survive should the thing suddenly drop.

I am intrigued by your plumbing suggestion. I get the general idea, but am confused about how the pieces would be connected (sorry if I am just being stupid). Can you please clarify either with a diagram or using words?

Question: my first thought is :what if the valve opens up on its own due to road vibration while driving? Do you have any concern/experience with that - or is there something you do to secure the valve in the closed position?

On the airbags and hydraulics - The chances of a sudden failure of either of these systems is infinitesimally small. That said - I've seen my coach with the jacks retracted and the airbags deflated - it does this while in storage if the jacks aren't down, and the front end is still far off the ground. In your scenario of being on the road and having little available time for maintenance, the chance of the air suspension failing is near zero - you would know it was leaking before getting under it b/c you would see or hear it. I tend to think this is a fear in search of a problem.

The ball valve requires a fair bit of force to turn, I seriously doubt it would ever turn by itself - but you could always just unbolt the handle from the valve and keep that somewhere else in the coach - then there wouldn't be any counter-force on the ball valve at all.

As for the assembly, here's the connections: Drain plug socket>>> 1.5" pipe nipple>>> Bushing>>> Ball Valve>>> tubing barb>>> oil drain bucket.