School Bus 101, long technical post

[Elliot]

This picture is from three months ago, and I'm still in love with the mural on the bus in the background. I want something like that on Millicent.

[Nipple]

as MDF said. Really want a bus, and seeing those roof decks just makes me want one more!

Every time I go to the airport I'm oogling the shuttle busses and thinking of the dirty, dirty things I would do if I were to get my hands on one.

[MyDearFriend]

Got my textbook in the mail yesterday and have progressed as far as Chapter 7: Engine Powertrain Components.

My goal is to understand Elliot's advice on How To Buy A Bus.



Oh and Grai I have already figured out that we should top our bus with that paint FIGJAM used on his playapod: Henry's Elastomeric Roof Coating.

[FIGJAM]

It's cheap!

Do the whole thing.

It will make a great canvas for whatever masterpiece you chose!

[Elliot]

I just read thru my original post and found little I would change.
Newer Allison automatic transmissions have four-digit designations like 3060. They are all good.
An "activity bus" is a school bus that was built for field trips. These often have advantages like big engine, more cargo space, and taller ceiling (for high school senior sports teams going to away games).

[MyDearFriend]

Activity Bus, yes that's what we want. Planning lots of activities.

Figjam, I don't know how that elastomeric stuff would take additional paint layers. But I guess we could slap some on a metal surface and find out!

Back to my reading: Engine Cooling Systems.

[Captain Goddammit]

I've forgotten if Elliot mentioned this, but ONLY buy a bus with an International DT466 engine or a Cummins 5.9 or 8.3.
Otherwise you'll very, very likely be very, very sorry. These two are proven super reliable and parts availability is great.
You can buy a gas-engine bus a lot cheaper, for good reason - it'll swallow fuel and be really slow-going. But, I think it's worth considering IF the Burning Man trip is the only thing you're gonna do with it and you AREN'T going to put much money or effort into a full RV conversion. If you go that route and it's a Chevy, try to get one with a 427 rather than a 366. Both are fine but the 366 will be REALLY slow.
But you really want a diesel. Especially a DT466. Ask any truck mechanic. They'll pretty much universally tell you that's the most reliable medium-duty truck motor ever built.

[ygmir]

I've forgotten if Elliot mentioned this, but ONLY buy a bus with an International DT466 engine or a Cummins 5.9 or 8.3.
Otherwise you'll very, very likely be very, very sorry. These two are proven super reliable and parts availability is great.
You can buy a gas-engine bus a lot cheaper, for good reason - it'll swallow fuel and be really slow-going. But, I think it's worth considering IF the Burning Man trip is the only thing you're gonna do with it and you AREN'T going to put much money or effort into a full RV conversion. If you go that route and it's a Chevy, try to get one with a 427 rather than a 366. Both are fine but the 366 will be REALLY slow.
But you really want a diesel. Especially a DT466. Ask any truck mechanic. They'll pretty much universally tell you that's the most reliable medium-duty truck motor ever built.

how about the CAT 3208? a friend has one.....fairly slow but seems to run ok.......NA.....and seems to run a little hot? Though I"m not sure I agree. He begins to panic at about 210.......I'm thinking it'd take 230 ok?

[Elliot]

Yes, I recommended precisely those three engines in my original post; International DT466, Cummins 5.9, and Cummins 8,3. (For new readers... the first post of this thread is PACKED with information, even if I say so myself.)

The Cummins 5,9 is rather small. It is powerful for its size, but there are hills where my bus with this engine drops to 25 MPH. When they first came out many years ago they had a serious mechanical "Achilles heel", but I doubt there are many of those left on the road. They are the most common engine in school buses.

If I had it to do over, I would look real hard for a Cummins 8,3 or an International DT466 to avoid losing so much speed on up-hills.

There are some engines you absolutely must not buy. The Detroit 8.2 is at the top of that list.

The Caterpillar 3208 is also on the list I would avoid. While the Caterpillar brand is generally famous for durability, the 3208 is the black sheep of the family. It was designed as a throw-away engine. I imagine some marketing genius dreamed it up -- maybe the same guy who decided to sell Yugo cars in the US.
Now, of course, I'll hear from hundreds of you who are having great success with 3208s, but as always... Your Mileage May Vary!

[Elliot]

It just dawned on me that this business of different brands of engines can be confusing to "civilians". After all, when you buy a Toyota or BMW or Chevrolet, you can pretty much expect it will have an engine of the same brand. Not so with buses and trucks. These large commercial vehicles tend to be assembled from components which are made by independent manufacturers, and the buyer can choose his preferred components.

For example, I used to work in trucking. When my employer ordered 20 new Kenworth trucks, he would choose between Detroit, Cummins or Caterpillar engines, and between different sizes of those brands. It's kind'a like having a house built; you can choose the appliances to be installed. You want a super-large bay window with blue glass? All you have to do is tell the architect and he'll make it happen. Same with trucks and buses.
Brand of engine generally depends on cost-effectiveness. A trucking company that replaces its trucks every two years might buy cheap engines, while a company that keeps its trucks ten years would probably do better to invest in the most durable engines.

And a school district in mountainous Colorado might tend to order larger engines than a school district in flat Illinois.

So when you shop for a used school bus, you will encounter all sorts of combinations. That's why we discuss brands of engines and other features as separate items.

[MyDearFriend]

It just dawned on me that this business of different brands of engines can be confusing to "civilians". After all, when you buy a Toyota or BMW or Chevrolet, you can pretty much expect it will have an engine of the same brand. Not so with buses and trucks. These large commercial vehicles tend to be assembled from components which are made by independent manufacturers, and the buyer can choose his preferred components.

For example, I used to work in trucking. When my employer ordered 20 new Kenworth trucks, he would choose between Detroit, Cummins or Caterpillar engines, and between different sizes of those brands. It's kind'a like having a house built; you can choose the appliances to be installed. You want a super-large bay window with blue glass? All you have to do is tell the architect and he'll make it happen. Same with trucks and buses.
Brand of engine generally depends on cost-effectiveness. A trucking company that replaces its trucks every two years might buy cheap engines, while a company that keeps its trucks ten years would probably do better to invest in the most durable engines.

And a school district in mountainous Colorado might tend to order larger engines than a school district in flat Illinois.

So when you shop for a used school bus, you will encounter all sorts of combinations. That's why we discuss brands of engines and other features as separate items.

And that is why I am reading up on what all these things mean.

mdfstudyingbus.jpg

(Additional illustration by Elorrum)

[graidawg]

full RV conversion.

sort of anyway. MDF will probably veto any ideas i have if they conflict with hers and she is the one with the book.

[MyDearFriend]

full RV conversion.

sort of anyway. MDF will probably veto any ideas i have if they conflict with hers and she is the one with the book.

Bwahahahahahahahaha, the person with the tallest pile of paper always wins, eh? Dunno how much veto power I really have if you are doing the actual work.

[theCryptofishist]

Oh dear. And all this time I thought it was he who payed the piper who got to call the shots on the conversion...

[Elliot]

There is one concern I may not have mentioned, because of the "out of sight, out of mind" phenomenon. Rust. Not much of it here in Northern California, and I've been thinking in those terms. But the majority of the US population lives in "rust country".

Some pointers....
There is a big dealer of used school buses in Florida. Good reputation so far as the paperwork of transactions go. But he gets most of his inventory from "rust country".
As with all used vehicles, the best place to get them is in the dry and mild southwest. No, I'm not volunteering as an agent! But you may want to keep this in mind.
Blue Bird buses have good rust protection in the form of galvanizing of the steel. Their "All American" models, which is their "deluxe" line, may have the most galvanizing. Other brands may have galvanizing also, but I don't know. When I look at First Student's listing of used buses, I see many noted as rusty.

[knowmad]

I'd like to throw my two pence in here...Gawd, as if you are not over whelmed enough! (also Kudos to you for doing the home work!)

I've forgotten if Elliot mentioned this, but ONLY buy a bus with an International DT466 engine or a Cummins 5.9 or 8.3.
Otherwise you'll very, very likely be very, very sorry. These two are proven super reliable and parts availability is great.
You can buy a gas-engine bus a lot cheaper, for good reason - it'll swallow fuel and be really slow-going. But, I think it's worth considering IF the Burning Man trip is the only thing you're gonna do with it and you AREN'T going to put much money or effort into a full RV conversion. If you go that route and it's a Chevy, try to get one with a 427 rather than a 366. Both are fine but the 366 will be REALLY slow.
But you really want a diesel. Especially a DT466. Ask any truck mechanic. They'll pretty much universally tell you that's the most reliable medium-duty truck motor ever built.

Betsy Duck was a 366 Chevy Up Front, She was slow (when loaded down), She was horrid on gas (when loadded) but also Predictable (read; Dependable provided you were prepared)
The 366 and 427 Chevy/GM Bigblock is a simple machine. Basically the same Gas motor that has been in use from the late 50's on. Spark, Fuel, Air. Provided you have good Tires, Breaks (don't get me started) and some one that understands the gasoline internal combustible engine you are practically good to go.
with one exception; the one that understands the gasoline internal combustible engine Should also be the one that understand the concepts of driving a Stick (manual) Transmission.
They'd also be the ones that will be able to talk to any one that may want to help you during a "Break Down".

In my experience working with Gas engines works better for me because the other mechanics I will meet on the way speak my language. and there are Parts on Every Chevy Slut out there.
yes I know that there are tons of DT466 mechanics out there and lots opf parts, bvut remember this those guys make thier bread and butter off of fixing Fleet Diesels not helping FuckedBusses get by.
let me ask one more thing; Why would you want to "do; Full RV conversion" if the (one or three time) use is East coast to BRC?
My bottem line is Diesel, for long term running-value; provided you kow about maitnence and logistics, and Automatic Transmissions is hella more reliable(?) provided you wana (can) throw $ out front.
The other Idea is you look at a cheep Gas Sled, buy cheep parts and be ready to work.
I have lived and worked a bus that made 4,500 miles a year, BM 2X, and hauled avg_1.25k ton/mile.
I often wish I had mechanical skills like Elliot or Yigy, and even if I did; I don't have the tools. I only need 10 tools to work on a Chevy. To fix a Diesel I would need a workshop.

Please remind me if I don't answer this thread. this debate is somehow important to me.

[Tiahaar]

My bus made it to the playa and back again, 10 trips and counting. Its a 40 foot GM 5301 former transit bus, 1960, with a 6V71 Detroit Diesel powerplant. Supercharged with a gear driven blower. 2-speed Allison automatic. Still runs great. Did my best road fix yet when the transmission direct drive solenoid died and swapped it for the neutral solenoid (they happen to be the same on this tranny). Don't need neutral anyways heheh. Best advice for a bus buyer I could give is get the mechanic manuals for your coach (body, electrical, axles, etc) & engine & transmission and carry them with you at all times. I'd of had a rough time completing that repair without them and the support of my trusty camping companions Rustie and Kisho, first time burners this year, and JK the guy on the left here. That's his Infinity Scanner project in front.

Camp Starship Palomino

Oh, CapSmashy thnks for the roof plank offer! I have a hay rack I may adapt for my bus top deck.

[MyDearFriend]

Tiahaar, that is totally awesome. Yes indeed I hear you on the mechanic manuals!

[BAS]

This bus is pretty much what I want. It has the following stats:
1995 International Amtran Genesis - 14 row - 83 passengers
DT466 (mechanical injection - no electronics) - 230 hp
Allison MT643 with locking torque converter
AIR BRAKES
Belly storage on both sides in the rear
AIR HORN
Side exit door
Roof hatches
6 emergency push-out side window exits
Heated mirrors
Tinted glass
AIR RIDE DRIVER SEAT
White roof
10 MPG coming to FL
SUPERB tubeless radial rubber on 10 hole Budds
Automatic tire chains, too!

Unfortunately, someone else has dibs on this one. I need to get the money, workspace, and other resources together. (I have just now realized I am not certain what a locking torque converter is, or if this bus has highway gearing. Some things I may want to know if/when I get serious about a purchase.)

I need to find where I put the graph paper notebook which has my sketches for what I want to do to, er, how I want to do the conversion.

[gyre]

Do your research before using a lockup.
Won't hurt to have it, except for past abuse.

Most of the southeast, though not all, is low rust.
Even most of florida is.
Not as rust free as desert country, but mostly predictable.

Temperature?
I'm not up on diesels, but sounds low to me.
I know that low temps can kill diesel mileage.
True on gas, but not nearly as bad.
They make some exotic cooling control systems for diesel pickups for this reason.

Most tuned gas engines run as hot as is safe, for efficiency.
The limit on my big engine is the cylinder head.
The engine could run much hotter otherwise.
But it is hot.
A friend found 10% more power running oil at 260 degrees.
He uses very precise controls on both cooling systems to run this warm.

[Elliot]

My thread is still alive!

First, let me respond to Gyre's post: Balderdash.

A torque converter is a part of an automatic transmission. It is the first part of the transmission right behind the engine. It controls the flow of power from the engine to the rest of the transmission. And a lockup torque converter is the way to go. All modern vehicles with automatic transmission have it.
The lockup feature works kind'a like the clutch in a stick-shift. It locks the engine and transmission solidly together so there is no slippage and thus no waste of energy.
Why do automatic transmissions not lock up otherwise? Think about it; with an automatic you can sit still while the engine is running, and the transmission is in Drive, such as at a traffic light. That's 100 percent slippage. Then, the more the engine speeds up the more the torque converter hooks up, kind'a like how you have to ease the clutch out smoothly when driving away from a standstill -- only, with the automatic torque converter this slippage goes on much longer.

And with an old-fashioned automatic, this slippage never ends. Even at full speed, there is some slippage -- maybe 5 percent. That translates roughly to a 5 percent loss of energy = fuel mileage. It also contributes to wearing out the transmission faster, and it is specially bad when carrying heavy loads and climbing hills, because slippage generates heat and heat is the most serious enemy of transmission survival.

So the lockup feature was invented. It is essentially a manual clutch inside the torque converter. It is pretty much the best automotive invention since rubber tires. It works completely automatically.
All MT600-series Allison transmissions have it. The AT500-series does not.

From all my reading on the skoolie.net forum I have learned that Florida Church Bus -- a man named Greg -- has a good reputation for friendly and helpful service. But as he says right near the top of his web page, he buys buses all over the country -- and that very much includes the most rust-prone states. So you should bring a skilled man to inspect any bus there (which is of course a good idea for any bus anywhere).

That bus sounds fabulous -- with one exception. The engine is in front, next to the driver. You can tell by the fact that it has a front grille. My Millicent has the same layout, and it is a beeeeeeetch to work on the engine. There is also heat and noise, although the engine cover is remarkably well sealed and insulated. So unless you absolutely must have a toy-hauler tailgate like Millicent, I suggest you by a pusher -- a bus with the engine in the rear. These are now quite common.

[gyre]

Balderdash what?

[BAS]

I actually would like to have a rear tailgate, since I would like to use the bus for heading for a location, parking it somewhere, and then exploring in an easier to maneuver vehicle. (A friend of mine suggested parking a Smart car inside. It'd be something small, but I would like to find a Diesel rather than something which runs on premium.) Also, for events like Burning Man, a big door in the rear would be easier for unloading camp material, especially if it is heavy. (If it isn't heavy, well, I want to put a full deck on the roof.)

At one point Florida Church Bus told me it was harder to get parts for a pusher, although that was about six years ago.

Maybe I could convert the "doghouse" into a nice large snack tray for long road trips or something.


Now if only I could figure out what I did with my notebook! I wanna play around with the design, especially since I don't seem ready to get back to sleep.

[Elliot]

At one point Florida Church Bus told me it was harder to get parts for a pusher, although that was about six years ago.

Maybe I could convert the "doghouse" into a nice large snack tray for long road trips or something.

The flat-nose front-engine (technically "forward control") buses like Millicent and the one you show a picture of have been going out of fashion for some years now. So pushers are entering the used-bus marketplace in growing numbers.

In Millicent, the doghouse (engine cover) definitely serves as a table for feeding the driver.
At other times it serves as a seat. People seem to prefer congregating up front with the driver rather than sit in the dinette and other seats behind.

[BAS]

Well, I may have a lead on a place to work on a school bus. While at the community bike shop I visited tonight, I found out someone in the same complex had apparently done a bus conversion more or less right outside the bike shop. Evidently the complex the shop is in has (aside from a metal recycling outfit) a lot of places where people pursue all kinds of projects. So, maybe, I have found somewhere where I could do some of the projects I have wanted to pursue for some time now.

[BAS]

The school bus I would like to get is no longer listed as being on reserve. If I can somehow get $9,000 before someone else buys it, and a work location comes through, two major hurdles would be out of the way.

[Tiahaar]

if one were to go to a certain e-auction site and search for 'gm' 'stainless' 'bus' one might find an interesting bus rv conversion project shell in S. Cal, if the elements haven't been too unkind to it. looks like someone got a good start, reskinning and adding new front/rear caps to a 5303 fishbowl, even started on the interior plywood and subfloor water systems...then aborted the project. good deal only if the running gear is in decent shape. ymmv and all that...

I hafta find a couple shift solenoids off of an Allison VH tranny for my bus...anybody have some?

[Elliot]

Great find, Tiahaar!

Let's see what I can tell from the eBay listing....

That's a fine bus in concept, although the price is awful high for an abandoned hulk. And because it is an abandoned hulk, I would call it a project "for advanced users only".

It was never a school bus, but was either a public transit bus or a long-haul bus.

He lists inside dimensions as 40' x 8', but this must be the outside measurements.

Bad: It has apparently been sitting outdoors with no windshield for four years, which means there could be rain damage to all the electrical equipment in and under the instrument panel. (Yes, it does rain once in a while in Southern California.)

Good: By the license plate, it is already titled as a motor home -- no special driver license needed.

Bad: The seller gives the brand name of the bus around four times, but offers no information about the condition of vital components like engine and transmission. (I'm guessing this may be an "abandoned property" sale by the storage yard.) This engine and transmission could be horribly expensive to overhaul. This is the old two-stroke "Screamin' Demon", rather obsolete now. Some owners of such buses upgrade to a modern four-stroke engine -- not cheap.
Repeat: Utterly unknown condition of engine and transmission. "Ran in 2009" means nothing -- it may have been driven 20 feet in a huge cloud of terminal smoke.

Good: All stainless steel structure. This is a unibody type bus; it has no frame -- the body serves as the frame. This is a perfectly good way to build a bus. And the body is all stainless steel, which is entirely rust-proof.
Cracks can occur and would require fancy welding, but this is a low risk. Stainless is very hard and thus difficult to drill holes in. It can be polished to a mirror shine and will stay that way quite well.

Not for beginners, but could become quite fabulous with enough skill and money.

[Tiahaar]

:D
Not for beginners, but could become quite fabulous with enough skill and money.

Yups! Its a later model of my 5301, a transit style rig, but with a lot of reskinning. I emailed the sellers, they are just looking to unload a project that got cancelled. New wheels and tires, good running gear, but some water damage inside which is a shame. If I had the room....2 busses!

[Elliot]

Six new tires would cost $2,000 to $3,000. And if they have realistic knowledge that the engine and transmission are truly in good condition, then this could be a good deal at $4,500. Still not for beginners, and I would expect to spend quite a lot on electrical repair. But yeah, this could be a worthy project for the right guy.
http://cgi.ebay.com/ebaymotors/GM-built ... 257af6aa14