Outdoor Adventure Bus Rig

[Buffalospiritgathering]

Hello there!
I'm James. I'm a musician and an adventurer, as well as a permaculturist.
I have a Corbeil 5 window School bus with a Chevy 6.5 naturally aspirated diesel motor with a 4L80E auto tranny and no dually.
I converted the bus to be warm and safe and hold everything I need for outdoor adventuring in any weather! I've got a cute little wood stove and a bed, water, storage, solar... It's cute!
I'm afraid that I made a mistake by purchasing the 6.5 motor. I've already had to change the flex plate and it's so damn slow, especially on hills.
Braking is underpowered as well, but this is easy to remedy with brake upgrades.
My mechanic says the injection pump is doomed at some point in the future and that replacing it will cost about as much as a motor swap. I've also got a blown heater core and (because it's a bus), the mechanic has to take it out to know how to replace it.
It's also turbo-less and all the parts are strange and not stock chevy parts because Corbail is defunct and the information isn't readily available about what parts they used.

What advice do you all have? The block is good, great compression, only leaks a little oil towards the back. It starts pretty easy, even in the cold.

I don't really want to ditch my beautiful project this far in if the injector pump fails. I am planning on taking it to the west coast, but I may have to do 15mph on the hills in the Rockies.

I just don't have the skill to do the big stuff. I can swap out parts, but my technical knowledge is limited.

I replaced the PMD and put in a heavy duty lift pump. What could I do that's efficient? Worth the money?

I honestly want a manual tranny and dually, maybe 4wd with a Lift, but I could just buy a pickup, you know?

Thanks everyone. Grateful for these forums.

 

[red]

Most mechanics nowadays can't diagnose issues if they can't plug into a computer and have it fairly accurately tell them whats wrong. Older engines don't do that (even the early electronic ones such as the 6.5). Essentially the usual statement is "It's too expensive to fix regardless of what the problem is."

Getting a turbo on that engine will be a massive improvement with power, but might require some sheetmetal work to make it fit in the bus. Should fit, but pics are needed to find out.

 

[Will L.]

Welcome to the forum James.

IF you keep 6.5- there are investments to make. Otherwise finding a duramax or cummins is in your future. Not cheaper to do a swap than install a new ip (injection pump) - that is a false. Otherwise most every older truck would have new cummins/dmax in them now.

A 6.5 with a ds4 injection pump (the kind that requires a pmd) without a turbo is about the dumbest thing I ever heard of in the 6.5 world.

Your local emissions standards might come into play. The ds4 ip (injection pump) was created so the computer can monitor fuel demand vs fuel delivery; to be able to shut down one cylinder at a time for diagnostics; and a couple other things that dont actually help lower emissions output. I just mentioned on another thread today kf the testing we did comparing tail pipe emissions output on same engine using a ds4 vs db2 all mechanical ip. The db2 wins EVERY category. Cleaner emissions, better mpg, more power, longer component life, lower cost of maintenance.
When the ip fails, rejoice and convert it to db2.

Meanwhile get a turbo on there. ATT, hx40, something in that range. The gm turbos are too small. You will see lower ect climbing hills, better mpg, and better power. The only downside is cost of purchasing/installing. My hummer is non turbo with turbo added now for instance. This isn’t theory talking, it’s experience. If you aren’t diy, more expense, but would be worth it to pay your mechanic to learn on this forum to save you money long term. I was factory trained on6.2/6.5 and much of that is simply wrong. More accurate info is here. Read the @WarWagon write up of getting a proper sized turbo vs gm tiny one and money saved from it.

ABOVE ALL, heat is #1 killer of this engine. 200 ok, 210 stare at gauge more than road, 220 pull over. That doesn’t mean hit 220 more than twice a year. Think of 220f engine temp as hundred dollar bills flying out the window.

There is a ton of info we can, and enjoy teaching here. But if you are going to swap to different engine, make that decision early.
budget for parts is primary point. Labor budget is debatable. But my current 6.5 is a hummer, and most wealthy hummer owners have taken to diy to avoid the pitfalls of paying someone to wrench on a 6.5.

When set up properly, a 6.5 is lower long term cost than duramax or cummins. If you want big power- wrong choice. If you are interested in alternative fuels, best possible choice.

 

[WarWagon]

Price the injector pump. A 100% new one is less than $2000. You can't get a good engine for that.

You can get some power out of a 6.5 to at least get out of it's own dammed way. Many on here have gotten some power out of these econo engines to make them livable with. This takes a good turbo as mentioned. You are limited by the NA precups you have. At the end of the day the reliability of the engine is not that great. So plan what you want to do: mod your engine or do a swap now. A new Optimizer 6.5 longblock with better reliability is available noting you may have "van" heads in the bus with a different intake angle.

Take it to the west coast via The Rockies ... You will think you died and gone to HELL if you try it without a turbo! I have bad memories of a NA 6.2 wound up in a 1988 Suburban in The Rockies aka through the Eisenhower Tunnel. I would have killed for a turbo to keep the smoke down and get some power in the upper RPM where GM automatics put things when the throttle is on the floor. What a miserable engine not far behind the gutless 454's that have no power in the upper RPM's either.

I happen to have so go fast parts for sale and videos that prove the 6.5TD can get out of it's own way. Not as well as some other choices, but, night and day over a NA, Naturally Aspirated, diesel. Bluntly my modified 6.2 Turbo'd would wax the floor with the gutless same year 1993 2500 454 gas pickup I am using at this time. Same precups you have and same low output NA IP.

Again you may be limited to a centermount turbo or crazy remote turbo mods like some van owners have done on here due to the "VAN" configuration of heads and no room on the passenger side of the engine bay. A GMx turbo is better than no turbo. That said I would swap the engine for something else because the GMx isn't that great in the engine ass kicking grades of The Rockies...

Here is GM turbo's vs. a big turbo that would apply to your heavy brick for aerodynamics bus:

The 6.5L Diesel Factory Equipped Asthma Attack

Online Diesel Community featuring news and articles on 6.2L, 6.5L and Duramax GM diesel engines, Ford Powerstroke, Chevy Cruise, lubrication and more.

www.maxxtorque.com

 

[ak diesel driver]

what year bus? if newer than 2000 you may already have the optimiser engine

 

[Buffalospiritgathering]

Well, from what I'm determining here...

1) It won't make it over the Rockies, because it barely made it through upstate NY. It overheated multiple times on a 10 mile steep mountain climb and smoked so badly that the people behind me couldn't see and the police came. It didn't have the capability to run with my foot on the floor without quickly overheating. This was about 1000lbs under maximum capacity with some windows open.
2) It has basically no room anywhere near the passenger side, so it would require custom sheetmetal to mount a turbo. I'd also need a different computer, a better cooling system and/or exhaust manifold improvements and may as well get the injector pump done and my heater core if we're going this far. How much would this run me? Any way that I could save moneys here?
3) People commonly swap in the newer Duramax, Cummins 6bt or get the $$$$$$ Optimizer engine setup for the 6.5. If I'm doing this, I don't see why I don't just get a pickup truck with a duramax or a cummins, because it'll have 4wd and hopefully a manual and probably cost about the same? Is this an accurate assumption? My only loss on this vehicle would be the $4000 I already put into it in repairs, plus the flooring, insulation, curtains and bedframe and mattress... about another $1500. Who think they'd buy a half completed bus project? Right, I think I may have to scrap the Buffalo bus? I definitely feel like I made a mistake, here. :/

 

[btfarm]

A Cummins swap is about the only thing I can think is reasonable to keep your project. Anything else is likely throwing good money after bad...

 

[Will L.]

you mentioned duals - that isn’t crucial for operation except stability in the wind. Doesn’t help the power levels one bit.

If you want a bus instead of a truck- personal opinion on use. Add pics of engine, engine compartment, under carriage,etc. there are vans, corvettes, etc that have a turbo mounted underneath and plumbing moves the no air. So a turbo not fitting in the engine compartment isnt a deal breaker.
price- labor is often way more than parts. You play your own music, and if I understand wiki correctly grow your own food(?). Might consider turning your own wrenches If you have a different car that is you daily driver for work and the bus is like an rv i take it- step by step we could walk you through most work on it.

overheating that bad- your mechanic should have done some testing to determine if you have a major problem going on, which it sounds like it.

Yes if you do an engine swap, often people buy a good running pickuo that has been crashed or rusted so the galue is lower and use that engine. If rusty just be aware engine bolts and parts might have rust damage also.

I have seen people get $60,000 into rv projects before they throw in the towel. The 6.5 is not a well known engine by most shops. IF a person makes ALL the proper upgrades it can last a long time and provide enough power and do it without burning a ton of diesel fuel. Like I mentioned also highly desirable for people that make their own bio fuel or run waste motor oil as fuel. It is a fuel efficiency designed engine which inreal world terms means not super powerful. But without a turbo they are just stupid slow.
Any new diesel engine worth buying or building is in the $8,000-10,000 range. You might find a smokin deal on Craigslist or a junkyard, but be realistic in cost when planning and maybe you get lucky and save some.

As much a 6.5 fan as I am, I can’t imagine if your engine is blown, putting another 6.5 in it. Same investment you could have a descent cummins or duramax. But because you will be paying labor if not diy - that can be insane cost. Hummer conversion, suburban conversions each customer would be ecstatic to only pay $15,000-$20,000 in labor. $60,000 for a complete swap isnot unheard of. Of you cant diy- finding an out of work knowledgeable person to do it with you might be your best answer.

i have concearn for you because you were upset over cost on flywheel- that is a cheap part. Diesels are not cheap. Most of us here do all the workon them ourselves not because we like turning wrenches but because we can’t afford to pay someone else to do it.
Seriously make videos and post to YouTube so we can hear/see it run. How it drives under load, so video from behing where we can see smoker and speed related. Post pics - although the decor might be cool- not important- engine bay, steering suspension.

Understand there are things we can tell you that are going to improve power and reliability- but I doubt two items will be under $20. What your budget is becomes a HUGE factor. How much labor is on it you have to discuss with your mechanic. We can let you know ifhis price sounds unfair most of the time- but bus and rv the labor is often ridiculous high because the way they stuff the engine in there. I had an rv that if the engine had same repair needed in a pickup would have been $200 but in the rv was over $10,000- no joke.

As to the ip - I wasn’t clear and should have been- it was the most commonly replaced item as being bad when it isn’t bad. So mechanics that don’t REALLY know this particular engine will replace them because that seems to be the issue frequently.

By your description, I can’t imagine not needing 2,000 in parts. You NEED a turbo which will involve exhaust and intake plumbing altering. Labor again will be way more than the parts if not diy- hoping to drive this point home. Your non working heater might be a huge part of overheating problem. Pics of how the heater hoses are ran to begin with can help. If they bypassed the heater core by plugging off the hoses- you have a simple fix there. On an rv that broke down herein vegas a month ago, he didn’t have a heater and was trying to get home to northern Idaho. His radiator was half shot. I helped him plumb lines and mounted a second radiator that looked stupid but bought him time, and at same junkyard we got a tiny radiator with electric fan and rigged it inside to keep him warm. It is some hack lookin stuff but will last him until he can afford to fix everything this coming summer and got him home. There is always options, well except no shop would ever accept liability of doing that so diy is as only option for him.

So-
1.post up them pics so we can see what space there is and id what you really have to work with.
2. Post video of it if possible.
3. Budget and time constraints.
4. Biggest money saving is labor.

 

[Jaryd]

What year is the bus

 

[Stoney]

Out of curiosity are you still in Ny? Just curious what hills you were on. The 6.5 ain't a power house by any mean..but if you can live with the lower power, there a hell of a lot cheaper to work on and keep running. Granted I'd love to put a 6bt in my dually but not in budget.. injection pump is a poa. But less than 2k to replace if you you wrench yourself..as said before, alot of us don't really like wrenching ourselves but saves a fortune..just my opinion but 6.5s are fairly easy to work on. Duramaxs are a little harder. And there's a lot of how to videos on youtube which I use alot. And guys on here are awesome about walking you through something..and this site is like the encyclopedia of 6.5 knowledge..plus there's almost always some one one line here you can message if needed.. without them my truck would be in a scrap yard already... Not trying to talk you into keeping the 6.5 by any means. But sounds like you run on a limited budget so doubt a swap is in the cards right now anyhow. I swapped in a set of 170 degree thermostats to get engine temps lower in hills. There's a bunch of simple mods you should do that are seriously cheap that help.. I know you mentioned that you swapped the PMD.. but did you remote locate it away from the engine.. such as down in the bumper it seriously helps.. and just because you have a new one doesn't mean it works good. always keep an extra cuz they will go bad without notice sometimes they'll last 5 years sometimes they last 5 days... If you're going to replace parts they're electronic especially make sure they say AC Delco on them cuz if they don't that engine will spit them out.

 

[WarWagon]

It overheated multiple times

It hasn't been asked, but, what exactly do you expect out of this project? Is it a Daily driver, RV, tour bus, home on wheels? I am confused as to why a pickup could replace it unless it's pulling an RV maybe? This could help you and us look at your goals and recommend some ideas like engine swaps, repairs, something else. It's not a loss of money at this point. It's a good project or saving you money IF you write it off and do something else. Depends on what you want to do and cost of something else vs. getting this going. Remember be Frugal not cheap.

What do you mean "overheated" exactly? Going over 210 on the temp gauge, spitting out coolant on the ground, temp in the red zone?

I am concerned that the engine has a cracked head, blown head gasket, cracked cylinder, or other source of combustion pressure getting into the cooling system. Is the coolant level low and the hoses get hard immediately after engine start when cold?

6.2 NA engines smoke some, however, they shouldn't be rolling coal to where the police come. There is a subjective fine line of how much smoke that's not clear here and too much black smoke can be an indication of a problem. All Smoke Matters! Is it white smoke, blue smoke, or black smoke?

Smoke show from one of my projects with major problems: https://www.thetruckstop.us/forum/threads/1992-6-5td-rescue.44332/

We do need the year as it's relevant to cooling system upgrades.

 

[Will L.]

Well, cant go by just year. AM General was 2-4 years behind pickups depending what parts your talking about.
I have seen 6.5 rv made in 1995 that had a factory n/a 6.2. Generators are even worse.
Many detailed Pictures are the same ly way we can see what is really there.

This wouldn’t be the first n/a ds4 I have seen, but would be the first in a bus.
I have seen shops tell customers they installed a pmd because that pops up frequently online, and met the owner at that shop to find a db2 on the rv. Hilariously they did mount a pmd on a heat sink and have extension cable to the db2- just no where to plug it in obviously. That one was fun- they had a $6,000 bill built up and by time I left with him that shop paid to have it towed to a different shop and sign off nothing owed.
RV/ Bus/ generators are way worse than pickups for getting a good shop to wrench on a diesel.

 

[Buffalospiritgathering]

The bus is a 2000.
The alternative fuels aspect and fuel efficiency is definitely one reason why I bought the motor.
I have had mixed success and failure with this project.
The heater core is plugged with bolts on both ends of the hoses. The AC system in the bus was completely shot and when I removed it, my friend who worked on military vehicles (not well, apparently) removed the fluid hoses and plugged them... yikes.
So on hills, it hit 220 once, but after that once it hit 210, I pulled it over. Only happened once, but I was doing 26mph on major highways uphill after that. No bueno.

If I attached the hoses, would it run again or is the heater core shot?
Anyways, back to the point, I've been struggling to find a mechanic who wants to work with me on this project. Almost everywhere I go, they treat this like a throwaway item. Very few people want to do work on this bus!
I'm capable enough that I can pull bolts and follow instructions, but I need CLEAR instructions. Diesel manuals so far have been off little clarity. I'm completely 100% capable of brakes, calipers, bleeding, changing filters, hoses & could probably do an alternator, but I haven't tried yet. Most of my work is with gassers and small cars... to give you an idea of where I'm at!

Here are some pictures. Engine bay from the front with coolant reservoir moved slightly and no airbox...
Alternator is basically up against the firewall.

Here's the link to my cold start video. No hard hoses!

Thank for the advice, y'all. Let's see what I can do here

 

[Buffalospiritgathering]

 

[Buffalospiritgathering]

 

[ak diesel driver]

Sure looks like the centermount turbo to me. Also the only hose your concerned with getting hard right away is the upper radiator hose. If your getting lots of smoke I'd suspect a turbo issue assuming you have a clean air filter

 

[Will L.]

good news on upper hose not getting hard.

Yup, that is a center mount turbo either gm6 or gm7- probably not working right, most common is lost vacuum to wastegate or waste gate solenoid, or stuck wastegate . That metal cover on the back top part of the engine is the turbo heat shield.

ENGINE OFF, Pull that cover off and grab the rod to see if you can move it by hand. The red arrow points to the vacuum wastegate controller. The metal rod opposite the side where the vacuum hose connects is what you want to move.

On the heater core- buy some heater hose and have it loop bypassing the bad heater core so he coolant flows from one point to the other. Blocking off flow on that greatly disrupts the flow and can contribute to overheating, but I think you’re engine is running WAY underpowered from no turbo and that is why so weak and so much smoke.

By the description you gave of what mechanical work you can do, you will do fine on this engine for 90% of the stuff to do.

 

[WarWagon]

Good videos and pictures!!!

As noted you do have a turbo and this explains a lot. GM made 3 versions of this engine in 1992-1993 the turbo being a HO, High Output, option. (1992-1993 was 6.2 NA, 6.5 NA, 6.5TD and after they dropped the 6.2.) So when someone says they got a NA engine we believe em.

So if you have black smoke, no power, and it acts like it's got no turbo: you are correct. Likely the vacuum system has failed. Vacuum holds the wastegate closed. Open wastegate means no "No Turbo Boost Mode, Michael" aka no power and smoke. Common failures are any of the hoses that connect the vacuum pump to the turbo wastegate control solenoid then to the turbo wastegate vac can. The rubber hose connections fail/crack often. Your vacuum pump could be locked up esp. with the slow RPM starting.

The Glow Plug/ wait to start light... After the initial long "on" time of the light you can fire up the engine. The Glow Plugs are the hottest then. The short flashes of the light "later" are to keep the smoke down on a running engine. I laughed with you when you waited for the flashes to stop before hitting the starter. Light goes off for the first time = "Hit It!"

Bluntly the starting sounded like crap. You have some minor but serious starting system problems. I am surprised it actually started. The starter went THUMP! and then literally stalled out a moment. It certainly isn't spinning fast enough to reliably start. Unlike a gas engine that can creep over and fire a spark plug: diesels need RPM to generate enough compression heat to light off the diesel fuel.

Tip for dual battery systems: Separate the batteries by disconnecting both of the battery grounds first. (Short a terminal to the fender undoing the ground and NOTHING happens.) When the grounds are both off you can disconnect the positive cables because nothing will happen if you short it with the grounds off the batteries. Then load test them separately.

Inspect the battery cables for corrosion. Find, unbolt and clean the battery cable engine grounds. If it's all good and batteries good: replace the starter. These starters have 4 brushes in them and can still spin of 3 of 4 brushes, but, really slowly. Get a new Powermaster if you need a starter.

Eventually you will learn to tell by ear if it's spinning slow due to a bad battery or bad starter. Well in AZ when the batteries blow every year or two due to heat... Video below gives you an idea, by sound, how fast it should be spinning over.

 

[Buffalospiritgathering]

Damn. It's got a brand new AC delco starter and flexplate. Less than 1000 miles. Brand new batteries with less than 500.
It's good to know there's a way to fix the turbo but this is the best it has ever started.

 

[WarWagon]

Damn. It's got a brand new AC delco starter and flexplate. Less than 1000 miles. Brand new batteries with less than 500.
It's good to know there's a way to fix the turbo but this is the best it has ever started.

Step back a second... G R O U N D S. We can't say to clean the grounds on here enough. Solves many problems often. Further battery cables internally corrode. Finally the positive connection where two cables come together is a common trouble area of the cable bolt being loose. Batteries can run down for a number of reasons like a light on etc.

Edit: I would take the fan belt off and check the vac pump as it may be locked up. The belt doesn't always make noise for that item. It's generally on the lower passenger side of the engine.