Lifting & Supporting the Bus

[Jim Blackwood]

Couldn't agree more. Too much weight involved to be taking chances with it. If that axle tips even a little bit that jack can shoot out of there like a rocket.

Jim

[luvrbus]

I wouldn't do with just the bottle jack with the standard round head but they sell a kit to use a bottle jack in the middle of a axle for the better brand of jacks for balancing the axle I have one for my Blackhawk 20 ton owned it for many years 

[GnarlyBus]

Ok. I'll setup one jack on each side (was already gonna do this on the drive axle) and go slow. Thanks for the answer.

I was thinking that the jack points near the wheels were for a flare tire or when only one area needed lifting. But it isn't really stable to lift on the axle with a bottle jack's limited grip.

[buswarrior]

Oh yeah, did we forget to tell you?

It doesn't happen in one shot...

Lift, crib, lower to cribbing, crib the jack, lift, crib, lower to cribbing, crib the jack some more, etc...

A jack squat enough to perform under the jacking points at low tide needs 2 shots at it.

And then the wheels are seized to the drum... and down it all comes... again and again...

Happy coaching!
Buswarrior

[GnarlyBus]

Updating this thread now to show what we ended up doing. I try to finish threads I start.Hopefully it helps someone who reads this down the road.

We got the jacks, ramps and stands out to grease up the rear end of the bus yesterday. This was our first time lifting the back of the bus up and it went very well. I flipped the dash switch to drain the tag axle air then flipped the valves in the engine compartment to finish draining the tag airbags. Then I backed over two 2x12s and chained up the tag axles. I don't think the chains I've put together were the right size (none came with the bus) as they weren't tight when the bus was up.

We ran up on 2x12 treated ramps. Those were made from an 8' on each side. We normally a board of two for leveling when we're parked. Then we used two 20-ton HF air jacks to lift the bus using the jacking points. We placed the jacks on 12"x12" squares of 1/4" steel channel we'd painted blue with tractor paint to keep them from rusting. (they have 1" lips on two sides and are often used for stair tread in industrial applications but we found them in the steel yard scrap bin. These steel squares were on top of 16x24ish 3/4" plywood to help spread the weight because we were on asphalt. Once we got it up high enough we let the axle down on the ramps and the body rested on the 22-ton jack stands (I love those things). We kept most of the axle weight on the jacks. So we had a some redundancy in case one should fail.

[GM Junky]

Yah I'm all for safety but it's starting to sound more like we're trying to bridge concrete with steel and park the bus on it. I really think the asphalt I'm gonna be on will be fine with the 11x11 foot pads of the jack stands. I
figure I'll add some 3/4" ply to spread out the weight a bit.

The drive tires are about a 12"x24" footprint on each side. Seems like getting close to that would be sufficient.

I'll crib up under the frame as a secondary security.

I do appreciate the input. Reading old threads on this topic people have a tendency to "one up" on each other on safety until someone suggests a pit! Nobody mention railroad ties either or all heck will break loose!

    I know it's an older post, but whatever you do, never work under the bus or any vehicle with airbags unless you shore up the suspension between the body and running gear. Never trust those airbags or rely on them to hold the vehicle while physically under it.

[HB of CJ]

Fancy way of saying safety first and always.  Dirt can compact.  Concrete can be too thin and crack badly then collapse.  Wood can compress then fail.  Even suspect cheapo foreign HD jack stands can suddenly fail.

What this all means is be very careful raising your Bus Conversion for ongoing fun easy doable maybe non expensive maintenance.  I enjoy doing such.  Others do not.  Consider HD redundant supports systems.  Be paranoid.

Do not forget to employ a dead level area.  Gravity has a way of sucking over time.  Have fun.

[windtrader]

Fancy way of saying safety first and always.  Dirt can compact.  Concrete can be too thin and crack badly then collapse.  Wood can compress then fail.  Even suspect cheapo foreign HD jack stands can suddenly fail.

What this all means is be very careful raising your Bus Conversion for ongoing fun easy doable maybe non expensive maintenance.  I enjoy doing such.  Others do not.  Consider HD redundant supports systems.  Be paranoid.

Do not forget to employ a dead level area.  Gravity has a way of sucking over time.  Have fun.

It seems like extreme comments about safety and not keeping it all top of mind. Nothing like a close call first hand to internalize just how different a bus is than a car. The weight and mass differences make all these considerations that one never encounters when working on autos and light trucks. I seen it up close and far better to be scared and caution rather than unaware of the lurking danger.

[GnarlyBus]

Yah be safe people. Here's a few sketchy videos I've seen on youtube.

This guy has a cool scenicruiser that he was out there removing the engine by himself! I set the video to start about 20 seconds before it falls off the bottle jacks he was alternating from underneath to try to lift the bus.

https://youtu.be/LKUOl_I1Abc?t=2381

Here's another one from Bus Grease Monkey. I love Scott's videos. I'm pretty sure I've seen all of them. They keep getting better and better quality. I've learned a lot from them. This video is crazy though. I set it to start a minute before the bus tips to the side (for the first time!). Watch the whole thing or move to the 31 minute mark for more jacking and blocking. Scott pulls off some crazy stuff that I didn't even know was possible. At the end of the video he says it would've probably been easier to just pull the whole engine/trans combo.

https://youtu.be/le06HE3caGw?t=1482

These links are not meant to bash the content creators. Let's not start a shame party. They're examples of how quickly a bus can come down if you don't use the proper equipment. Be mindful of these when you plan how you'll lift your bus.

[Jim Blackwood]

OK, consider this: If you had all the weight of the bus (40K lbs in this example) concentrated in one spot, a mere 1 degree angle in your jack off the vertical (in reference to gravity) would generate 700lbs of directional force. Half that is still 350 lbs.

So it's pretty safe to say that any time you jack the bus you are going to have hundreds of pounds of force trying to push it off your supports. If it moves any at all the angle will increase and the force will increase geometrically. If you look at a sine table that's pretty obvious.

Now then. Is your jacking point absolutely flat? Well it won't be once you start to lift the bus. Once again, that will generate side thrust.

Lifting heavy vehicles is all about controlling those side thrusts and they can't be taken lightly. (ha) That's why you chock the tires and build a wide base with your cribbing. It's not about the tire contact patch size, it's about controlling any and all lateral movement.

Jim

[Jim Blackwood]

Years ago I built a pit to service our bulldozer. You know those concrete barricades you see at construction sites, the square ones that stack? Yeah, I bought three of those. Had to bring them home one at a time since they weigh 3,000lbs each. Used a spot where there was a drop off and used the dozer to cut a trench, position the blocks in a "U" shape, and then fill in around them so the approach was level. I was a little concerned about the blocks tipping in but it worked great and has been stable now for many years. Awhile back I poured a concrete floor in it and I had already put a steel plate to hold the dirt from falling away so I didn't even need a form.

Unfortunately I have an out-building in the way so getting the bus on it would be an adventure, not that it couldn't be done. I'd have to cut down the wild cherry trees on each side of it though. (btw the dozer is long gone) It is constructed so I could use the lower approach as a loading dock if I had to.

Jim

[windtrader]

Jim,
Thanks for finding and posting a physics formula computation. From personal experience, there is a lasting image burned into my mind at the awesomeness and power of off center heavy weight in action. The bus was up on a bottle jack and being lowered. For some reason (no chock block and raised off ground on a very slight incline) the bus starting moving laterally forward. As it got off center hardly at all, it looked as if the bus literally jumped off the jack and lunged forward.

Off center 1, then 2, then 3 degrees, the lateral force increased so the jack became a lever and launched the bus off. It really did accelerate off, not a graceful slow tilt and drop.
Hoping not kicking a dead horse but just communicating a real wakeup call for those having plenty of passenger auto experience and now working on super heavy vehicles like buses.

[Jim Blackwood]

Yeah, all that heavy stuff acts that way. Actually the light stuff does too but it's just not as scary. If your bumper jack starts to go you can grab it and pull it back. If you try that with your bus it won't make any difference and it could kill you.

In that video did you notice that the guy at one point had two blocks against each other about half way up his stack? It would have been just as easy to have spread them apart. He was creating multiple opportunities for the bus to move, and move it did. He's just lucky it didn't move with him under it. It seriously reminded me of those Third World videos where a guy has a truck tilted over and held up with a 2x4, working underneath it.
You guys called him Scott, I hope I'm not offending anyone on this board, but often there are only small differences between dangerous and safe and if you don't know what those are, then you are probably risking your life to try this.

Jim