Tip Starting the engine before raising the jacks

[skychs]

@RandyB the issue you had above is the shuttle valve. At the end of the jacks being raised a 12V signal is sent by Equalizer to the chassis system to close the shuttle valve so it can air up. I had one that was sticking which they replaced under warranty, not a big deal, but I had times where I would not air up. The resolution to that is to cycle the jacks as you did and one other procedure that FL would tell you to do over the phone that I don't want to share here as it is to be done only when and as directed if you can't air up.

The shuttle valve setup in the Ventana is why I think we cannot air up with the jacks down.

Each coach and each model year seem to have very different setups, oddly. I don't think anyone can really say do this or do that in a broad sense. There are different systems and different cutouts Newmar and the Chassis vendors put in place which seems to be constantly changing.

I agree. Even though you may have the same model/year as someone else, they are all a little different. What works for you may not work for others.

 

[CaptainGizmo]

It's very interesting all of the opinions and techniques of when to extend the slides and now for the first time in four years I'm hearing techniques on how to extend or retract the slides. @CaptainGizmo you had my attention for something you said which was to have the engine running when running the jacks due to the electrical demand on the hydraulic pumps. Until now I thought yeah, that makes sense, I never have the engine running when I run jacks up or down. Today I realized that I'm always on shore power when running the jacks as that's after I've deployed or retracted the slides so I think that point is moot. It could be something of interest when boondocking but I think we're always on shore power when it's time to deal with jacks.

There are different jack systems and different requirements. Most of you I think have HWH jacks. I have Equalizer. I don't think I could air up with the jacks down, the shuttle valve is open and the air will escape, it will not fill the air tanks from what I recall. For my specific setup I have to have jacks up to air up (prior to installing HWH Active Air which completely changes the game for my procedures). But for a typical coach with an Equalizer jack system I don't think this is possible. For anyone out there (@RandyB - do you have equalizer) maybe you can clarify.

I've never had an issue airing up after raising the jacks, i.e. airbags empty. The compressor will inflate the bags and continue to run until the pop off valve indicates air tanks full. I don't understand how it matters if your air tanks are full at the start of airing up vs. not, for those that have this capability. I personally would rather have a slower fill to ensure the airbags are seated and positioned properly. Ever had one that had to reset itself, it sounds like a cannon going off! You think you blew an airbag.

Anywhoo, the thought just occurred to me on the power part of this discussion and that I'm personally always on shore power when it's time for leveling.

Neal,

The OPs question was why “Start the engine BEFORE raising the jacks.”

That’s the basis for my answers. Being on shoreline is fine to supplement the electric demand of the pump, for sure. But, if your bags are flat, and your air tanks are low (like after a long sitting), YOU MUST RUN THE ENGINE to get the bags inflated.

Granted, yes on shoreline, you “could” raise the jacks without the engine on...but you’ll still be sitting’ on the ground. ;-)

 

[RandyB]

@Neal
I had to move the coach today, so I experimented with the Equalizer and coach engine interface. So, FYI:

First, I lowered the jacks from fully stowed. All lights indicating all four jacks are not stowed. The engine started without issue.

Next, I thought I’d see what happened if I released the parking brake. The moment the brake was released, auto retraction of the jacks was initiated.

With brake reengaged, engine running, the jacks can be run up and down at ease.

 

[Neal]

Thanks @RandyB - I think the specific scenario for testing in "our config" is if you can air up with jacks down.

This thread obviously brings to light there are many different configurations, lockouts, etc. based on coach model, model year, components used for jack systems.

 

[RandyB]

Ahhhh. Starting the engine and actually airing up can be 2 discrete functions. I guess I’ll try that next. With jacks deployed, bags deflated. Start the engine. Do the air bags inflate while the jacks are deployed? Or only after retraction.

 

[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.)