Tip Starting the engine before raising the jacks

[Neal]

The engine will start, no question there. The question with our setup was whether or not we could air up with jacks down (obviously engine running) and I don't think we can with our setup. The shuttle valve won't allow air to the bags I don't think, you can hear air hissing as well IIRC. My setup is different now with HWH Active Air but I was just making a point that not everyone can air up with jacks down as recommended in this discussion by others.

 

[RandyB]

Alright. I got back to the coach and here’s what I found out.

with Equalizer leveling system:
With jacks deployed and air bags deflated.
Started engine and no inflation of the air bags.

Retracted jacks while the engine was running. The moment the jacks got to the stowed position, air bag inflation began.

So, relative to the original post, starting the engine while the jacks are down would provide no real advantage other than filling the tanks (as stated in post #1). In the experiment above, with tanks at full pressure, the rise to ride height was quite slow, in my opinion. Apparently the valves have really small orifices.

 

[skychs]

Last weekend I did a little experiment. I started the engine with the jacks down and let it run at "low idle" for two minutes. At two minutes I retracted the jacks. Once the jacks were up the coach started to rise immediately. I didn't set the timer again but by the time I walked around the coach the air bags were full and the relief valve was releasing pressure. Over the next couple of trips Im going to shorten the engine run time to see how it effects filling the tanks and raising the coach. HWH system.

 

[Old-RV'er]

It's been so long since we used the coach I don't remember what I do! I think we do it this way.
Park in spot, allow coach to get to ride height, put out slides, lower jacks. Auto Level is a joke, so I manually level coach using buttons, once finished. Engine is ON for ride height achievement, then shutdown, key in ACC or ON position, extend slides, then jacks down as stated.

To leave park, key to ACC or ON, raise jacks, start engine to achieve ride height. Once RH achieved, put in slides. If engine is warm, shut down, dump tanks, flush tanks, put stuff away, do walk around, make sure antenna is down, start engine and leave site. If available area to hook up toad, get on highway for next place.

 

[bobnjill410]

Ditto to Old-Rv’er. Our pattern exactly.
( but our 2016 DSDP, will air up the bags with jacks down and engine running of course.)

 

[Joe Dutchstar]

Interesting here at The Mothership the tech started the engine prior to (edit) retracting the jacks. When I discussed the air bags popping when settling into position after coming off jacks, he said that is why he starts the engine before lowering the jacks.
Starting the engine and letting the airbags inflate some keeps the airbags from popping.

 

[team bradfield]

I'm confused on the sequence, if I put my jacks down it auto dumps the air, so I can't put slides out a ride height, what am I missing? I've always put slides out, then jacks down

 

[J&JD]

If you put the jacks down manually the bags will not dump unless you manually dump the bags. If you choose auto level the bags will dump prior to jacks going down.

 

[DennisT]

Is it maybe start before raising the jacks and not start before lowering?

 

[Joe Dutchstar]

My mistake for the confusion. Edit statement to say retracting jacks.
With the bags fully deflated the bags are bunched up. In this configuration the mounting plate maybe slightly askew.
Hence when they finally take a set, many times it is with a sharp pop or crack noise. Sounds like a rifle shot to me. Very alarming.
The techs comment is when this happens in the shop with all its hard surfaces, it is quite loud.

 

[Wemustrv]

While I was on the phone with Freightliner the subject of when to raise the jacks came up. We have discussed the sequence of slides to jacks but not engine. They suggested starting the engine before raising the jacks. His explanation ... by starting the engine first ... it fills up the air tanks. With the air tanks filled, when the jacks come up the air bags/suspension will fill up faster. I have started to do that and Im really surprised how much faster it is.

I can run my levelers without the engine both on extend and retract. The leveler system lowers airbags prior to leveling. I have always felt that the jacks should be down and rig level prior to running out any slides. Just my reasoning and how I do it. I am no saying others are wrong by any means. This reduces the amount of available twist on the chassis as it takes the suspension out of it. Also very hard on the leveling system to have the slides our and then run the levelers.

 

[Richpatty]

Interesting... I start the engine and almost immediate pull up the jacks, but have not heard any noises. I know if I wait too long to pull the jacks up, I will start to hear the air escaping from the system as lets the air out of the bags even as it is trying to fill them up....so I feel I need to pull the jacks up pretty quickly otherwise the bags will never fill. Pulling them up "closes" up the dump valves so the bags can be filled. At least on my unit..

Or am I missing something?

 

[Roadglide117]

Wow. For once, a no-brainer to answer. ?

You absolute are best to start the engine while/before raising the jacks. The engine runs the compressor which WILL replenish the tanks at the same time the bags are filling!

You’ll hear the pop-off/dryer valves vent and you know you’re topped off, and “on the bags”.

“On the bags” at “drive height” is the Perry much THE standard recommendation prior to moving slides; whether in...or out.

Wouldn't be so bad if the loud alarm wasn't going off to wake neighbor campers

 

[Roadglide117]

I can run my levelers without the engine both on extend and retract. The leveler system lowers airbags prior to leveling. I have always felt that the jacks should be down and rig level prior to running out any slides. Just my reasoning and how I do it. I am no saying others are wrong by any means. This reduces the amount of available twist on the chassis as it takes the suspension out of it. Also very hard on the leveling system to have the slides our and then run the levelers.

That's my thinking too..level is level..at newmar everything is level..easy to say to extend slides the way the system was built...not all campgrounds are level...I look to see if all corners on all slides have a gap before i extend any slide. Sometimes jacks go down 1st

 

[Joe Dutchstar]

Tried to level at KOA South Louisville. Systems was having problems. Racked the chassis so badly the doors would not open. Ended up stowing the jacks and tried our best to position the coach to a better position.
And the alarm when the engine is running and jacks deployed is annoying.