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Outdoor Adventure Bus Rig

Yeah, bad vacuum pump will drag the engine down like that and cause no turbo- but I would think the belt would smoke it up from a stuck Vpump.

flywheel is not something that normally needs changed. But hard starting engine can burn up starter and that can damage flywheel. So the secondary damage may have been fixed but root cause still there.

pick which ever seems easier to ya first. get wastegate to move by hand or remove the belt.
 
So, I went through the motor... WOW I DO HAVE A TURBO.
The dowel attached to the vacuum pump moves freely by hand. (2nd pic)
@Will L. I should probably just replace the vacuum pump? There is a small bit of smoke sometimes when I am at foot off the gas, going downhill, but otherwise, not really. If the vacuum pump is toast, you're saying the belt would smoke?
It's attached the serpentine belt with everything else on it?
Sorry about excessive ?s... total noob. I can't exactly see it!

I also noticed this little issue on the valve cover (I think it is)... where there's this open hole and there's oil in there... as should be in a valve cover, but I never noticed this issue before since the last time I went to the mechanic... but Can't blame him because, truthfully, I barely know enough to say anything IMG_20201203_131701423.jpgIMG_20201203_131652995.jpgahahaha
That should probably be plugged with something?
Where could I get that? What's it called? (first pic)
 
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That hole is where the CDR goes (diesel equivalent of a PCV). The large hose that connects to the CDR, at least on trucks, connects to the intake just before the turbo. On the vacuum pump if it spins and feels ok check how much vacuum at idle. Should be a minimum of 20". Hard to tell from pictures on my phone but it almost doesn't look like a vacuum line is attached to the turbo.
 
Houston you have a problem... I actually looked on my bros bus...its basically set up same as on truck, cdr ,tube, into turbo intake...if hole going into turbo intake is wide open she's sucking dirty air from the engine compartment which could smoke the turbo.. need to check turbo for damage..I'm not a expert on turbos. But one of the guys can give you advice on checking it out better than I can.
 
I know you mentioned NY and it looks like your on the way into figuring out your issues. Just thinking another member (including me) could be nearby to assist. Sounds like a multitude of little issues with nobody willing to work on a dinosaur 6.5L (especially crammed in that engine bay!).
 
DieselSlug said:
I know you mentioned NY and it looks like your on the way into figuring out your issues. Just thinking another member (including me) could be nearby to assist. Sounds like a multitude of little issues with nobody willing to work on a dinosaur 6.5L (especially crammed in that engine bay!).
Click to expand...
For real a good idea. Someone that has spent time working on this persnickety engine is worth a trip if possible. Most the diy folks on here are worth paying more than a “pro” mechanic in a shop that doesn’t know this engine- this from the guy that did it pro for many moons.
 
Hey guys just letting you know, he's down near new York City. I'm about 5 hours from him so can't get to him unless he babies it thru the Catskill mountains this way, which with a mechanical problem like that I wouldn't advise, probably never make it up those hills. I go through them on occasion hauling trailers and some of them are a b****. I know we got a guy over in bath, and another guy near Albany not sure if anyone is down by the city.. I mistakenly took it when he said upstate New York as that he was more in the central area of New York..hopefully there's somebody down in that area
 
why not.
the leash damper lets all the exhaust go to the turbine worm.
it takes a lot of exhaust to start building up pressure.
 
Stoney said:
Hey guys just letting you know, he's down near new York City. I'm about 5 hours from him so can't get to him unless he babies it thru the Catskill mountains this way, which with a mechanical problem like that I wouldn't advise, probably never make it up those hills. I go through them on occasion hauling trailers and some of them are a b****. I know we got a guy over in bath, and another guy near Albany not sure if anyone is down by the city.. I mistakenly took it when he said upstate New York as that he was more in the central area of New York..hopefully there's somebody down in that area
Click to expand...

Ah I got ya. Yeah I'm Syracuse so I am a good trip away as well if he is down near NYC.
 
Eh, well I do have a friend who is factory trained in cummins. If I can't figure some shit out, he may help.

Basically what it looks like is that I want to compile a list of things I should do to diagnose this motor and, if it doesn't have major problems, update or correct everything left and start driving it in the spring. She's off the road right now.

What would be the breaking point for anyone here?
Hate to admit it, but I've got a pretty decent budget that's available, but I'd like to keep it under $20000 if it's gonna be a keeper. I keep vehicles for a long time. That's why I bought a diesel.

So my turbo may be toasted... Gotta check vacuum pump and see if running 20psi at idle... If not, replace pump. I honestly think the turbo is probably toasted. The vacuum lines to it are all gone and the "hole" which should have the sensor isn't obviously set up...

Then if I buy a turbo, I should get a hx35, right?
Upgrade exhaust manifold.
Upgrade exhaust.
Gapless rings.
I should probably just get the DB4 IP put in now.
Replace heater core
Upgrade radiator and fan.
I'll so search the list on the write up on the 6.5 asthma attack later ..
Has anyone manual swapped a 4wd rig into a bus? Having a hard time figuring that one out. Everyone seems to like the 4l80e, but I hate automatics. :// I want a NV4500.

I read the article about the 6.5 asthma attack. Interesting stuff. I'm not reading it right now, but I'm definitely interested in knowing some more ..
 
Buffalospiritgathering said:
Eh, well I do have a friend who is factory trained in cummins. If I can't figure some shit out, he may help.

Basically what it looks like is that I want to compile a list of things I should do to diagnose this motor and, if it doesn't have major problems, update or correct everything left and start driving it in the spring. She's off the road right now.

What would be the breaking point for anyone here?
Hate to admit it, but I've got a pretty decent budget that's available, but I'd like to keep it under $20000 if it's gonna be a keeper. I keep vehicles for a long time. That's why I bought a diesel.

So my turbo may be toasted... Gotta check vacuum pump and see if running 20psi at idle... If not, replace pump. I honestly think the turbo is probably toasted. The vacuum lines to it are all gone and the "hole" which should have the sensor isn't obviously set up...

Then if I buy a turbo, I should get a hx35, right?
Upgrade exhaust manifold.
Upgrade exhaust.
Gapless rings.
I should probably just get the DB4 IP put in now.
Replace heater core
Upgrade radiator and fan.
I'll so search the list on the write up on the 6.5 asthma attack later ..
Has anyone manual swapped a 4wd rig into a bus? Having a hard time figuring that one out. Everyone seems to like the 4l80e, but I hate automatics. :// I want a NV4500.

I read the article about the 6.5 asthma attack. Interesting stuff. I'm not reading it right now, but I'm definitely interested in knowing some more ..
Click to expand...
Don't jump off the deep end yet and just start throwing parts at it. You may very well be fine. Check for any play in the turbine shaft on the cold side (where intake connects to). If no play I would continue running what you have, you will be much happier once that turbo is working. I bet thats why it was so easy to overheat, throwing fuel and not enough air. Lots of unburnt fuel is heat!
 
Honestly almost better if the mechanic never worked on a cummins. Complete difference and that knowledge will make him think he knows what he is doing with this one- huge mistake. DONT buy a single part until you know when your whole plan is.

And no I wouldn’t go hx35. Hx40 or a 35/40 hybrid, or ATT. Did @WarWagon sell his turbo and converter yet? If not that would e a a good set up if you stick with automatic.
Stick shift might be funny- You sit farther forward in a van (bus) than pickup. Maybe a custom shifter system and adding clutch pedal asset would be custom also. So plan that out separate when you decide $10,000 is worth that change alone.

imo, having worked on bunch of the gm6 turbo 6.5 in vans and bus, I wouldn’t even fix it. Rip that crap off and ebay it for a few bucks. Get a big boy mechanical controlled turbo on there. Find out if hvac uses vacuum or not. If not, loose the vacuum pump too. A well-sized turbo is crucial moving more weight and wind resistance.
 
It would be major custom to change that turbo to something else. Maybe not as bad as a Hummer. This is one mod that would pay you back in MPG increases. I wrote the 6.5 asthma attack article.

Keep in mind this engine doesn't have the HP at low RPM to back up the TQ. I had to learn how to lug the Cummins over revving the 6.5 when I got one.

Unless the IP has a problem: save your money. Then only buy new and consider a DB2 mechanical IP conversion. Plenty of wore out junk being sold as rebuilt. The electronic DS4 with the bad PMD design - just YUCK! For the kind of money a new IP takes a DB2 conversion without the electronics to screw up is worth it.

Buffalospiritgathering said:
What would be the breaking point for anyone here?
Click to expand...

Have you priced dropping a Cummins conversion in?

Again what do you expect from this rig? Miles per year?

I would replace the vacuum lines and see how well it runs. This problem is keeping the turbo from making any boost and likely limping the ECM to reduced power mode. Then see what else needs fixing. Most important is engine condition for blowby. You mention gapless rings: bluntly forget about rebuilding a GM cast 6.2/6.5 engine. They are known to crack main webs, heads, cylinders, head bolt holes... For a rebuild cost: it's not much more to buy a new Optimizer longblock and put gapless rings in it before install.

We don't have enough information to say what the breaking point is. I suggest you don't have enough info to start on the wish list just yet. The main concern is getting everything done on a conversion and the engine blows up. Are you willing to drop another 6.5 in this?

I don't respect the "Let's slap an OD section on this..." NV4500. Plenty of better MT's out there to be worth the pain of putting one in. But I wouldn't bother as the 4L80E is good enough and cheap enough to rebuild.
 
Get a CDR and tube on there before you drive it.

Replace the vacuum pump lines. The vacuum pump should read 20”s of vacuum. Or go with a manual set up but you will need a boost gauge to set it up properly.

On the radiator, I would get in touch with @Twisted Steel Performance and see if he has a welded aluminum-coated radiator for your van. He is a forum sponsor.

If you want a heater core that last get a Brassworks heater core.
thebrassworks.net

Search: 52 results found for "Chevy heater core"

Restored radiators, street rod & hot rod radiators, custom bespoke radiators or drop in replacements. We build them all.
thebrassworks.net thebrassworks.net

https://www.65turbogarage.com/ This is a good website that you can learn from. The author Mark Hinkle is a member here.

If you are going to keep it I would upgrade the oil cooler lines and put a 4” exhaust with a 3” down pipe on there. LeroyDiesel sells that stuff and is a forum sponsor. https://leroydiesel.com/
 
@WarWagon If I choose to keep this, it will be a mobile touring rig & self-contained house. Lots of miles every year as I play my music in various cities. I'd honestly like it to be capable of towing a trailer and possibly hauling stuff that's tied up to it... like logs. I'm buying some land in the near future and will be building on it.
I haven't priced out a Cummins drop in., yet.
If the motor died, I think I'd have a hard time scrapping the frame, with all the work I put into it. I know it's not worth a whole lotta money, nor is any of my work "fancy" but it feels like home. It would be hard to let it go.
I want something that ticks like a clock and starts right up and can drive through most anything. After 2-3 years, I'd like to know every nook and cranny of that thing and be able to fix it all.
I don't mind the 6.5, honestly. I just found a site that talks about all the transmissions that bolt up to it. Found out something new today.
I think a Cummins would be unlikely for me, at this point. Optimizer 6.5s with a working turbo arent too bad compared to a new pickup!
 
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