Sojourner

[eyedeal.ink]

Originally Posted by sojourner

Hey Nat,
I'm not going all the way back. Gonna make a turn and go out just ahead of the rear wheel (eliminate some really weird unnatural bends). I know Diesels aren't quite as loud as gassers either especially with bigger pipes (mine looks to be 3-1/2"). I want to keep things as simple and trouble free as I can and that huge muffler is heavy and just in my way.

I was thinking of doing the same, only I wonder if exhaust at the back windows would be an issue? Have to make sure they're up when you're driving?

[jazty]

Originally Posted by eyedeal.ink

I was thinking of doing the same, only I wonder if exhaust at the back windows would be an issue? Have to make sure they're up when you're driving?

Good point. I remember reading about exhaust gas exit requirements in the MTO (Ontario's DMV) documents that the exhaust must exit behind any opening that goes into the cabin. Pickups can dump the exhaust before the rear wheels, box trucks can dump exhaust underneath the vehicle behind the cab, etc. I don't remember all the details. Hell, I don't even remember if they were requirements or simply recommendations, actually Something to think about, anyhow. Nobody wants a cloud of diesel exhaust pouring in a window while stopped at an intersection.

[sojourner]

I have even considered running the pipe up through the cabin and out the top. We used to do "dry stacks" like that on some commercial boats instead of water cooling the exhaust. Ceramic blankets make this possible. Not sure I want to go to all the trouble though (unless I get caught up in the whole deep fording thing ).

As far as the windows and fumes, we're taking out all the school bus windows and replacing with RV types from our donor travel trailer in the locations we want. There'll only be one window aft of the exhaust outlet (bedroom) and that one will be closed while traveling.

[opus]

This is quite satisfactory, 2nd best to a stack but I've yet to see a good looking stack on a bus. Yarded the muffler off a long time ago too.

[sojourner]

Cool exhaust exit in the rear bumper. I can see that being pretty easy on a rear engine. If (big "IF") I do the stack it will be through some sort of cabinet with a good amount of ceramic thermal blanket filling the whole area floor to ceiling. I'll probably just exit in front of the rear wheel. Very simple, shorter run and less bends = more efficient engine.

[Tango]

I'm looking at having mine exit in front of the driver side wheel also. No windows from there back, so that's a non-issue for me. Will go with the largest diameter I can stuff in and no muffler. Will likely transition from the stock 3" to 4" pipe (stainless, if I can afford it). Since the Cummins exits on the passenger side, getting it over to the driver side will probably be the trickiest part. Course...there all those tanks & things to weave around too.

Don't want it coming out on the passenger side cause that would dump the exhaust right where I hope to be sitting under an awning sipping rum drinks and there are times when running the engine while camped is a necessity. Also looking into a removable riser stack similar to what is avail for gennies that can be put in place while parked to get the fumes up higher.

Seen some nifty fixed stacks, just don't forget the "flapper". Not only keeps rain out, but I've heard of birds & critters moving into stacks if the unit sat for very long.

[sojourner]

I'm looking at having mine exit in front of the driver side wheel also.

I'm coming out the passenger side here. Can't honestly see why I'd have to run the engine much while boondocking (doing solar for power and wood for heat). As Nat stated getting the pipe out the other side will be problematic. The main issue will be going under the driveline. You'd be better off coming out at the rear of the axle and then making the crossover. Personally I'm planning on putting my water tank (55 gallon drum) just aft of the differential between the frame rails.

[Tango]

Actually, I,m looking at putting the crossover above the bell housing rather than under anything. Given the way the exhaust exits the turbo on mine, it looks like it might make for a cleaner arrangement.

But then, I haven't started bending any pipe yet either!

[sojourner]

Tango,
What model do you have? I'm assuming a front engine. You might be careful when considering that option. The highest heat you have is right out of the turbo. Running that close to the floor might cause a fire and even heat issues with the transmission. I don't think any of us relish the idea of a fellow skoolie "flaming out". There typically isn't that much room between the floor and bell housing for air circulation to cool the pipe. One thing's for sure, it's gonna be a tricky pipe bending job with the larger pipe bends. Probably a better option is to use close bends and weld the whole system together.

[ol trunt]

Hey Tango, Sojourner has a point about the heat load. My bus has a water cooled crossover behind the cyl head and above the torque converter and I had to go to all sorts of extremes to keep the heat out of the bus body. I think I'm going to cross my pipe over just under the center joint in my drive shaft and then terminate it where you plan to. With our short wheel bases I don't see any problem with high centering as even with a 4" pipe the pipe is still well above the body line at the center of the bus.

[Tango]

Howdy Sojourner --- My bus is a '46 Chevy that I'm putting a little Cummins 4BT into. And you are absolutely correct in that the header pipe coming off the turbo gets extremely hot. But because the engine & tranny are back a ways from the original 6 cylinder, I have already cut out the firewall and begun building an extended doghouse that will be very heavily insulated for both heat & sound. Still gonna be a tricky fit, but right now it looks like I can cross over behind the engine and above the trans without the bends getting too tight. The turbo and that part of the exhaust will also be either jacketed or treated with ceramic shielding or both. Keeping the heat in helps the turbo spool quicker with the added benefit of there being less radiated out into its' surroundings.

Will be a while before I can determine just how much room I have in there to work with, but I am in complete agreement with all your considerations. I've talked to a couple of folks who have stuffed the same engine into their Jeep CJ's (a really tight fit) and just about every one of them has issues with the amount of heat that gets transmitted. I'm hoping that I can resolve them on mine with the right combination of space & insulation.

[sojourner]

Hello gang,
Haven't had much to post for a while as I have been doing some other projects around here to clear the schedule so I can get back to work on Gimel (the name of our bus, Hebrew for camel). I've been building a very large aquaponics system and since I started construction over 3 years ago (been traveling the world helping others get theirs going) I really needed to get it out of the way before embarking on another large project, namely Gimel. I have had the chance to sneak over and do a couple things on it though that can be done quickly with a minimal amount of financial outlay. For one, I dropped the exhaust system and removed the muffler, cut up the pipe pieces as needed, welded them back together and straight piped it exiting just in front of the rear wheel. Yea, it's a little bit louder but after seeing the muffler, I'm glad I did. The muffler was rusting through around the bands that held it in place. I've been going over the whole thing removing whatever is not going to be needed for our purposes such as air supply to things like guard and stop sign mechanisms. I'll use the connection point and valve later for an air horn. I removed the power steering reservoir (very bad location) and pulled the hoses down and will make a new one that will fit in the side door compartment under the drivers side window where the electrical (most of which has been removed). A much better location as it's easier to check and fill and will get two less hoses running under the engine (who ever came up with that idea should be dealt with). I'll be re-purposing a dual oil filter remote bracket I have to filter the power steering oil. I know it's overkill but it's what I have on hand. Been eying the cooling system, namely the rear heater and it's related 365,000 ft. of hose (some of which are hanging down under the engine, arghhh), various valves and hardware running everywhere. I sure wish there was a flow chart available to help make sense of what they did designing this thing. Some of it, just doesn't make sense (once again the conflict between engineers in a cubicle and us service type guys working in the field). I do have one part though I'm trying to identity. It's a cylinder mounted just behind the right bumper that has coolant hoses coming in and out and a vent hose connected to the "tree" of hoses on the radiator fill neck. I'm attaching pics. Can anyone help me identify it and what it's purpose might be? I want to get rid of everything that's simply not needed and simplify this thing all around.

Looking through the tow hook cutout on the right side front bumper.


Looking up from the ground.


Looking up from the ground.

[sojourner]

Any ideas on what the tank under the front bumper is?

[sojourner]

Hey Nat,
That's what I thought when I first saw it but there's no other hoses running in or out The cooling hoses for the trans are running to and from the radiator. I have a MT643 (thankfully!!). Strange piece of equipment and I can't seem to get any information from International (they are no help with anything this age). I do know this, if I ever do come across some service information, I'm going to make it available to this group. I've worked on engines since I was a kid (and professionally for over 25 years). This one has me stumped. I want to eliminate what is not needed and this looks like a candidate as I suspect it's part of the ridiculous heater system I fully plan on reworking.

Thanks for the reply.

Trav.

[opus]

Do you have a transmission retarder?

[sojourner]

Hey opus,
Not sure and I doubt it. This bus came from Plainview, TX and I can't even imagine them ordering a bus with one since you can see across three counties in that part of the state. I see nothing other than what appears to be a standard tail shaft on the transmission. I might just have to pull it down to see just what the heck it is.

Thanks,
Trav.

[opus]

You'd have one of these handles if you did:

[sojourner]

No handle like that on the bus. I'm thinking it could be some sort of aux. expansion tank for the rear heater. There are no other hoses except for two 1" heater hoses, one running to the rear heater and the other to a housing on the right lower front of the engine that has 2 hose barbs. The other hose is attached to the upper one.

Trav.

[sojourner]

Hey Nat,
No ports closed off. It appears to be nothing more than a tank made from a pipe with a hose coming from the rear heater circuit and the other from the engine. A small bleed hose (3/8") comes from the top to a fitting on the fill neck next to the radiator. I suspect to bleed off any bubbles. It may be surge tank of sorts given the extra volume of coolant with the rear heater. Lot's of strange things on this cooling system. For instance, the overflow tank is mounted well below the top of the radiator and has an extension on it to fill from the side door.

Trav.

[sojourner]

Spent any available time the past couple days simplifying the wiring harness up front. What a mess of unused wiring!! It always bothers me when I see bundled wires with terminals on them that have never been used. My past career was as a yacht technician and I've done several custom builds from basically a hull and engines doing the DC wiring and all related engine systems from install to delivery. I've always had a "thang" for keeping things neat, tidy and SIMPLE!! The guys who developed the wiring on this bus seemed to go out of their way to make long runs just to drop a ground or something like that. I know being a line built thing there is a generic wiring harness that crosses several models but while it may be good for production, it just plain seems a waste. Needless to say, where possible, wiring runs are going to be a lot shorter. I was able to remove all the wiring from the side drivers door and when I replace the box it will have nothing but the relocated (custom built) power steering reservoir and a water separating fuel filter. This will make it much easier to access this for service in the future. I found the fuse panel under the dash to have a lot of extra capacity so the one I took out from the side panel will not be needed at all. Like I said, amazing how complicated they make these things. Either some engineer wanted to make sure he was needed or someone there had stock in the wiring supplier and was getting a healthy kickback. At some point I'll pull the dash panel and build a corvette style panel (like the older semi's) with full gauge compliment as I acquire the parts and materials. I already have the sheet stainless steel to have the panel made from. Just gonna have to figure out the woodwork and how to integrate it into the dash. Should be pulling down the cooling system and get the unneeded items out of there as well. I's so looking forward to making the chassis as simple as I possibly can. Much easier to work on. Another upside to all this is, while I don't have a wiring schematic, I am getting familiar with the color codes (totally different than any boat or truck I've ever worked on (who'd of thought white would be a color for a ground on a DC system)) which will make it easier when it comes time to finish up the DC electrical.