Skoolies At Last!!!

[TheVermeulens08]

Hello everyone from the oldest town in Texas! Nacogdoches is our hometown and me and my wife and 3(soon to be 4) children just bought our first bus!
An 1989 7.3 IDI International bus with volunteer body. We drove 4 hours north to look at her and we broke two belts on the test drive and spent 2 hours tracking some replacements down and getting them installed(we just replaced all 5).
We made it home slowly and surely, think the max speed at hit was 63 on a downhill on the way home. On flat ground It would maintain 55-60 once we got some momentum, but boy did going up hills drop my speed down to high 40's or low 50's(Does anyone else have the same problem?). I plan to put it in the shop soon and get everything checked out.
I am aware of the cavitation issues they can have and plan to buy the pretreated fluids soon.
The bus was converted two owners ago into a livable skoolie, passed on to the next man who gutted it because he didn't like their floor plan and their carpentry work. He lost his job in the oil industry and sold it to us with all the supplies he bought to re-re-renovate it as well as everything he salvaged from scrapping it. So were down to an empty bus with only some flooring in it and the insulation was started.

My first question that someone could help me with is wether or not its imparative to have the foam sheet insulation under the flooring? The floors are done with a layer of tar paper and then plyboard/OSB. Will that work or are there major issues with that?

My family and I are very excited to start this life changing project and sharing it with all of you!

 

[sdwarf36]

Welcome.
As the saying goes-YMMV. What are your plans for it? Weekend camper-full time small house? Travel around the world?
If you are just camping-and much of your time is in Texas-I'd leave it. A month in Alaska? Well thats another story...

 

[claydbal]

howdy neighbor! just across the sabine river from yall. if planning on staying close, your floor wont get real cold. i have celotex 1/2in, then osb 1/2in. the floor is usually 10 degrees cooler than the ceiling and is easily heated. rust may be a different story however.

4 hours north? oklahoma?

 

[TheVermeulens08]

The plans

Yes we did drive to the shores of lake Texoma to look at it and decided to bring it home.
As of right now its just a camper project but as money is available it will be converted into a full time tiny house.With space for 4 kids bunks!Am I crazy!? rent and bills are just outrageous these days. Once we can live in it we plan to travel up northwest for seasonal summer jobs and find a place to settle down with weather that knows how to make up its mind!

 

[claydbal]

no, not crazy. thats my intent also. oops, we both are crazy!

 

[cowlitzcoach]

It would appear as if you have a pretty good foundation on which to build your tiny home.

In regards to your top speed and slowing down on the hills, it all is determined by which engine, transmission, and rear end gearing you have.

With a 190 HP engine it is going to struggle to go highway speed or go up any hill.

With a 4-speed Allison AT540 or MT640X transmission you have no overdrive so your top speed is limited by your rear gears.

Most school buses of that vintage with diesel engines have rear gearing to limit top speed to about 57 MPH.

Your options to change those parameters are only limited to how much $$$ you are willing to spend.

Most diesel engines have a little room to increase HP. If you have the T444 engine without a turbo the easiest way to increase is to get a Banks turbo kit. The engine is essentially the same as the 6.9/7.3L. Banks developed the turbo system that IHC ended up installing at the factory.

Whether your engine already has a turbo or not any HP increases will come from adjusting the timing and the pump. Again, a lot of information that applies to diesel engines in Ford light duty trucks will apply to your engine. It also may require changine injectors.

Increasing your HP will help on the hills but won't change your top speed. You can only change your top speed in two ways--increase your engine speed or change rear end ratios.

Increasing your engine speed by changing the governor setting is a good way in which to blow your engine up. So I would not suggest that as a good alternative.

There are two ways in which to change your rear end ratio. The easiest is to put taller tires on the rear. If you currently have 10R22.5 tires going to 11R22.5 or 12R22.5/11R24.5 will increase the height of your tires and change your rear end ratio.

The only other way is to actually change the gears in the rear end. Somewhere on the rear end there should be a little metal tag that will give you the rear end ratio. If that has disappeared you can raise one of the rear wheels and count how many times the drive shaft turns for each full revolution of the tire. At a guess you have gearing right around 5:1.

If you PM me your VIN and e-mail I might be able to get the build sheet for the chassis for your bus. It will tell you exactly what was built into the bus and sometimes even specifies which rear end ratio was used.

When my mother-in-law passed away very unexpectedly my wife had to go to Grand Rapids, MI to take care of everything. In order to get two of her mother's cats and a lot of "treasures" back to WA state we purchased a 1984 IHC/Thomas bus with a non-turbo, non-electronic T444 engine and Allison AT543 transmission. It was geared to a top speed of 65 MPH but quickly ran out of steam on any hill.

Drafting behind semi-trucks really showed how much wind resistance had an impact on how hard the engine had to work. While drafting it was easy to maintain 65 MPH with about 3/4-throttle. Once out of the draft it was pedal to the floor to maintain 65 MPH.

Changing gear ratios to get the engine speed down at a particular speed won't necessarily also result in lower fuel consumption. Speed and wind resistance are the two biggest fuel users in a bus. Reduce either and fuel consumption goes down remarkedly.

Changing gear ratios to get more speed without changing anything else will usually result in slower speeds up hills. Or at least require downshifting sooner.

Since you indicated you had to replace all of the belts before you headed home I would guess it has been quite a while since any other maintenance has been done. Clogged fuel and air filters will really slow you down as well. You won't notice it under 35 MPH unless they are really clogged. But at highway speeds or climbing hills when you need the maximum amount of air or fuel and you will discover even a little bit of clog will drop your speed on a hill noticeably.

Good luck and happy trails to you and your family.