4 safety stands

Topic: 4 safety stands (Read 785 times) previous topic - next topic

4 safety stands

October 21, 2021, 04:54:12 pm

I want to leave the coach on safety stands over the winter so the coach does not sit on the tires. I have 4 safety stands. Where should they be positioned in front of the front axles..behind? On the rear behind the tires or in front?

Re: 4 safety stands

Reply #1 – October 21, 2021, 05:16:15 pm

I would prefer to block it under the axles.

Re: 4 safety stands

Reply #2 – October 21, 2021, 05:21:53 pm

With only four stands use one in front of and one behind of the tires on both sides of either the front or the rear axle. I expect it is not a good idea to put the stands in front to the tires on the front axle and not behind and then let it settle.

You could just go get a chunk of Douglas fir or treated Southern Yellow Pine 4x4, (Douglas fir will have more compressive strength), measure how long you need at normal ride height and cut 8 blocks. They will be about 7" long. Cut them all the same length, maybe a bit less than ride height so they fit in without having to raise the coach up. When you start the coach and it goes to ride height they should be easy to get out. Put a big sign on the inside of the windshield to remind you to remove the blocks.

Technobabble ahead...

Douglas fir has about 7,200 psi compressive strength parallel to the grain. If the frame is 2" wide x 3.5" for a 4x4 that is about 50,000 lbs capacity per block. More than enough for this task.

Treated southern yellow pine has about 1,300 psi compressive strength parallel to the grain. So using this for posts for the same conditions above you would have about 9,000 lbs capacity per block. Sufficient for this task.

Re: 4 safety stands

Reply #3 – October 21, 2021, 05:40:51 pm

So I'm so confused. How would putting the safety stands get the weight off the tires? You need to jack and use 20k jack stands on a stable platform to unload the tires

Re: 4 safety stands

Reply #4 – October 21, 2021, 05:44:23 pm

Quote from: dsd – October 21, 2021, 05:40:51 pm

So I'm so confused.

I think Peter (the OP) means he doesn't want the air bags completely deflating and the coach setting down on the mechanical stops to where the tires touch the top of the wheel wells.

Re: 4 safety stands

Reply #5 – October 21, 2021, 05:51:26 pm

Dsd
I have air leaks. I can level it or leave it at ride height. Either way after about 4 days coach wheel wells are resting on the tires. Plan to have the entire coach gone over for air leaks in the spring but for now just want to keep the coach wheels off of the wheel wells. The AH exhaust is about 1/2 inch off ground when it rests that low as well

Am I thinking the right way on this?

Re: 4 safety stands

Reply #6 – October 21, 2021, 05:52:51 pm

Other than easy access I see no problem. Heck my coach sat at least 2007 to 2020 flat
Scott

Re: 4 safety stands

Reply #7 – October 21, 2021, 05:54:58 pm

Chuck
You are correct. Maybe I did not relay that correctly

Re: 4 safety stands

Reply #8 – October 21, 2021, 06:00:45 pm

I set one safety stand along side each air bag.

Re: 4 safety stands

Reply #9 – October 21, 2021, 06:11:27 pm

I thought you wanted to tires off the ground. To block the air bags you need
8 stands.

Re: 4 safety stands

Reply #10 – October 21, 2021, 06:47:06 pm

Aren't these coaches designed so that sitting on the wheel wells is fine?

Re: 4 safety stands

Reply #11 – October 21, 2021, 07:06:14 pm

Jeff, that is probably correct and perhaps if you lowered the coach to the stops on purpose it would be OK. But if your coach looses air at different rates from one corner to another then short blocks might prevent any unnecessary twisting.

Re: 4 safety stands

Reply #12 – October 22, 2021, 12:21:27 am

Quote from: Roger & Susan in Home2 – October 21, 2021, 07:06:14 pm

Jeff, that is probably correct and perhaps if you lowered the coach to the stops on purpose it would be OK. But if your coach looses air at different rates from one corner to another then short blocks might prevent any unnecessary twisting.

Lower the coach using the HWH control panel.

Re: 4 safety stands

Reply #13 – October 22, 2021, 09:51:42 am

dicksop, we have the torsion bars, so take this with a grain of salt.

As long as my tires hold air, I don't worry about my tires taking a set when sitting.
If you want that added level of protection against tire damage caused by a tire sitting without air, the jack stands need to be centered on the wheel or doubled up, one under each air bag.

FWIW I use a square of plywood between the jack stand and the garage floor, when I had a garage. Just to help spread the weight. It's amazing what 1/2" of plywood can do to help spread the load.

Re: 4 safety stands

Reply #14 – October 22, 2021, 10:05:08 am

Quote from: dicksop – October 21, 2021, 04:54:12 pm

I want to leave the coach on safety stands over the winter so the coach does not sit on the tires.

Once again - the OP doesn't want to keep his tires off the ground...he wants to keep the coach (top of wheel wells) off his tires. Different deal.

Always interesting (to a English major) how various readers can interpret a simple sentence in entirely different ways. One of the reasons (N American) English language is so difficult for foreigners to comprehend.

Re: 4 safety stands

Reply #15 – October 22, 2021, 10:18:22 am

When I arrive at a RV park and the site is level, I drop the coach down on the tires! No issues! Hope this helps!

Re: 4 safety stands

Reply #16 – October 22, 2021, 10:44:29 am

Expanding a bit on what Roger and TGordon and Joe said (above), excluding a blown air bag or other abrupt system failure, there are two ways a coach can end up lowered down on the mechanical stops:

1. The operator can uses the HWH control panel "LOWER" and/or "DUMP" buttons. The HWH brain will let the air bags deflate. If the coach sits on level ground, all 4 corners will be allowed to hit the mechanical stops, and the tires may touch the tops of the wheel wells. If the coach is parked on uneven ground, a safety protocol included in the HWH program goes into action. The intent is to prevent the coach frame from being twisted when one front tire sits on a higher (or lower) surface relative to the other. Excerpt below from HWH 600 Series Service Manual:

"The front manifold has a right and left air pressure switch. When the pressure in one front air bag drops to approximately 10 psi, the opposite side front air bags will be inhibited from exhausting any more air whether in automatic leveling, pushing a down arrow in manual leveling or pushing the "DUMP" button."

2. The coach may also end up all the way down on the mechanical stops due to gradual leakage of air pressure from the suspension system. If the HWH system is turned fully OFF (IE not left in AUTO LEVEL mode) then it has no control over the gradual sinking of the coach. Regardless of the parking surface, eventually the coach may end up all the way down on one or more of the corners. The danger here is possible twisting of the frame, which may result in windshield glass being displaced or fractured.

SO, If there is any question about the levelness of the parking surface, it behooves the owner to take steps to ensure the coach cannot assume a twisted stance. The easiest way to do this is to activate the HWH Auto Level function. If this is not possible or practical (due to battery drain) during long term storage, then it is suggested to use some kind of support stands or blocks - one placed next to each air bag.

Re: 4 safety stands

Reply #17 – October 22, 2021, 11:56:53 am

It is Incredible how much I learn from one question (although I presented it a bit wonky) thanks to all. Although my parking pad for the most part is very level ( there is a slight difference between the front and rear as the the front sits almost on the tires and the back with a little space between the wheel well) I think twisting of the frame would be extremely minimal so will just auto level and shut it off. Oh to have perfectly level cement pad..that would be so nice....some day!!!
Peter

Re: 4 safety stands

Reply #18 – October 22, 2021, 01:37:01 pm

Quote from: dicksop – October 22, 2021, 11:56:53 am

Although my parking pad for the most part is very level . .. .
Peter

Maybe the safest thing to do would be to make up some shim-pads to place underneath the low wheels so that all four wheels are level to one another for the off season. Jacking up each corner to insert the pads is easier on the frame than for it to sit slightly twisted for months on end.

Re: 4 safety stands

Reply #19 – October 22, 2021, 02:22:31 pm

Quote from: dicksop – October 21, 2021, 04:54:12 pm

I want to leave the coach on safety stands over the winter so the coach does not sit on the tires.

Okay Chuck you made me go back to double check my lack of education. In reading this there is absolutely no reason for the tires to clear the coach IMO, however when storing long term for me I want the tires off the ground to prevent flat spotting. I clearly see what you are saying and clearly overlooked what was being asked for. Sorry. Back to function over form.
Scott

Re: 4 safety stands

Reply #20 – October 22, 2021, 03:44:48 pm

Quote from: Old Toolmaker – October 22, 2021, 01:37:01 pm

Jacking up each corner to insert the pads is easier on the frame than for it to sit slightly twisted for months on end.

And, driving up on them is ever easier on everything.

Re: 4 safety stands

Reply #21 – October 22, 2021, 03:57:53 pm

If you level the coach with the auto-level function and leave it on any air malfunction at all will turn on the pump and it might run for days or weeks before you notice it. And Dick's small HWH pump will be toast. We are in cold country, when my coach is put away for the winter nothing is on except a smaller battery charger that maintains house and start batteries.

And Dick, inflate your tires to the max sidewall PSI while stored. Mine are at 120 psi. If you leave in the winter it is easier to let air out than to add air when it is cold. Higher pressure in the tires resists flat spots as well.

Re: 4 safety stands

Reply #22 – October 22, 2021, 04:10:07 pm

during covid time I have left the coach blocked up with my
11 inch steel pipes. I don't want the air bags squished and
I never let the tires touch the wheel wells. the fact that they can
touch the wheel wells in my mind is a design flaw.
plus, when it is blocked up I can scoot under it any time I feel
lucky enough to catch an elusive air leak

Re: 4 safety stands

Reply #23 – October 22, 2021, 05:41:35 pm

If the coach tires flat spotting is a real concern (it is not to me), they DO make so called "Tire Cradles" that are supposed to prevent this from happening. I have no knowledge of them. Pretty pricey, but I guess some owners might consider them worthwhile. Link to one example below, but they are also sold on Amazon, eBay, and other online outlets.

The Home Depot Logo

Re: 4 safety stands

Reply #24 – October 22, 2021, 06:32:26 pm

Quote from: wayne m – October 22, 2021, 04:10:07 pm

during covid time I have left the coach blocked up with my
11 inch steel pipes. I don't want the air bags squished and
I never let the tires touch the wheel wells. the fact that they can
touch the wheel wells in my mind is a design flaw.
plus, when it is blocked up I can scoot under it any time I feel
lucky enough to catch an elusive air leak

Foretravel did it for a reason when they went from jacks to air leveling. It is engineered that way.

Affiliate Notice