School Bus Conversion Resources

School Bus Conversion Resources (http://www.skoolie.net/forums/)
-   Mechanical and Drivetrains (http://www.skoolie.net/forums/f33/)
-   -   Engine Too Small!? (http://www.skoolie.net/forums/f33/engine-too-small-26185.html)

EastCoastCB 03-14-2019 06:53 AM

Engine Too Small!?
 
So I'm browsing the auctions this morning and found something funny.
They're selling 2011 buses in AZ because the emissions engines are too wimpy. I guess this is the kind of school district that typically bought 8.3's till they became unavailable.

https://www.publicsurplus.com/sms/au...ew?auc=2297682
Quote:

WAS TAKEN OUT OF SERVICE BECAUSE ENGINE TOO SMALL

Ronnie 03-14-2019 07:58 AM

A lot of Arizona is flat, but from Mesa to Heber is a 7000 ft difference. Other parts of the state have some real mountains too. So I can see where these buses would have a real struggle.

Booyah45828 03-14-2019 08:29 AM

I don't know if I buy that. The ISB was available with up to 300hp IIRC.

The reason they eliminated the ISC is because it's power production overlapped the ISB and ISL. No need for cummins to have 3 engine lines when 2 will suffice.

I'd bet they have issues with the emissions on this guy. We've had a lot of trouble with the 2010 and 2011 models. Seems the '10 emissions systems in the early years aren't as robust as the later years and are expensive to repair. A lot of injectors, egr coolers, turbos, particulate filters and catalysts have been replaced to keep them in service.

Emissions equipment on diesel engines sucks. You take what once was a reliable engine and knock years off it's life with that crap. That's why manufacturers are bring back gasoline/propane/natural gas engines. A set of plugs every 50k miles is cheaper then 1 new diesel injector.

brokedown 03-14-2019 09:54 AM

That's funny.

Ronnie 03-14-2019 09:57 AM

300 hp might be available in a pickup, but seems 200hp or so is the most available in buses.

brokedown 03-14-2019 09:59 AM

Quote:

Originally Posted by Ronnie (Post 314497)
300 hp might be available in a pickup, but seems 200hp or so is the most available in buses.

I have for sure seen 230hp ISB, in fact the recent post of buses in Oregon I believe are all 230hp ISB. I haven't seen above that but I haven't really been looking either.

Booyah45828 03-14-2019 10:22 AM

https://www.cummins.com/engines/isb6...n=School%20Bus

It was offered. What the districts usually buy is something completely different.

Kinson 03-14-2019 11:51 AM

Quote:

Originally Posted by brokedown (Post 314498)
I have for sure seen 230hp ISB, in fact the recent post of buses in Oregon I believe are all 230hp ISB. I haven't seen above that but I haven't really been looking either.

I just checked an Oregon listing and the description says "CM550 260hp". CM550=ISB. Are they not allowed to reprogram/mod these?

Ronnie 03-14-2019 06:58 PM

Quote:

Originally Posted by Booyah45828 (Post 314500)
https://www.cummins.com/engines/isb6...n=School%20Bus

It was offered. What the districts usually buy is something completely different.

Thanks for the link. I wonder what would be involved in bringing up the HP on these buses?

Kinson 03-14-2019 07:38 PM

Quote:

Originally Posted by Ronnie (Post 314541)
Thanks for the link. I wonder what would be involved in bringing up the HP on these buses?

Maybe a computer tune and exhaust mod would help? I also hear about people messing with propane injection on older engines.


I forgot to mention that the 2010 model has the 6.7 version of the ISB with full blown emission equipment. It performs worse than the 5.9.

EastCoastCB 03-14-2019 10:00 PM

Quote:

Originally Posted by Kinson (Post 314545)
Maybe a computer tune and exhaust mod would help? I also hear about people messing with propane injection on older engines.


I forgot to mention that the 2010 model has the 6.7 version of the ISB with full blown emission equipment. It performs worse than the 5.9.

Probably what they mean by "engine too small".

Booyah45828 03-15-2019 02:03 PM

You'd have to get and compare the build sheets between the low hp and high hp models.

It miight be no difference, or it might be bigger injectors, different pistons, different turbo, etc.

It'd be nice if it was just a simple software switch and be done, but nothing is ever that simple.

Truthfully, pulling the emissions equipment off makes a world of difference in the trucks. Almost night and day. I've never done it on a bus before, reason being is that they're publicly owned leaving only me to assume responsibility for doing such a thing.

cowlitzcoach 03-20-2019 04:21 PM

A lot of school districts stopped ordering the ISC or the ISL for the simple reason that on school routes the engines never worked hard enough to get warm enough to make the regeneration system to work correctly.


One local school district started spe'c'ing the 250 HP or 285 HP ISB. In order to use that HP you have to use a whole lot more throttle on an ISB than on an ISC or ISL.


I have been seeing more and more school districts getting rid of their newer buses as soon as they can while keeping in their spare fleet any of the pre-2000 model buses they still have.



One of the problems with any of the 2000 and newer fully electronically controlled engines is even with a battery cut off switch there is still a small parasitic load on the battery to keep the computers alive. Over time the battery will go dead. Do that enough times and you have to replace the battery(s).



Move up to the 2007 and newer fully smogged engines are concerned, the maintenance and repair of the smog systems is constant and expensive.



If you have an unsmogged bus with no electronics that is always ready to go with a twist of the key why would you get rid of it in favor of a newer bus that is a garage queen?


I think the value of the pre-electronic and particularly the pre-smogged electronic buses will go up while the used market for electronically controlled smogged buses will head towards scrap value very quickly.

Bigfoot18 03-21-2019 12:06 AM

I made allot of money fixing the new junk caterpillar is selling. People are fools if they buy any Tier4 final engine. They are all junk no matter the mfg.

EastCoastCB 03-21-2019 06:25 AM

Quote:

Originally Posted by Bigfoot18 (Post 315384)
I made allot of money fixing the new junk caterpillar is selling. People are fools if they buy any Tier4 final engine. They are all junk no matter the mfg.

Yes sir this is correct.

cadillackid 03-21-2019 06:42 AM

pulling the emissions off is tricky.. however there are software programs floatin g around so you can do DEF / DPF / EGR deletes.. and the hardware is out there too to do it...



you cant just rip the parts off as the newer computers are pretty damn tough to fool.. however not all markets these engines are sold in requure all the emissions.. mamy of these engines have off-road uses which have much relaxed emissions, or are sold to "emerging markets" where regulations are scarce.. so they can be sold cheaper with none of that equipment.



the computers are the same on them all..


I know there are "people" successful in deleting emissions on Maxxfirce engines making them actually pretty reliable an more powerfull as a result..
-Christopher

Bigfoot18 03-21-2019 12:25 PM

Quote:

Originally Posted by cadillackid (Post 315400)
pulling the emissions off is tricky.. however there are software programs floatin g around so you can do DEF / DPF / EGR deletes.. and the hardware is out there too to do it...



you cant just rip the parts off as the newer computers are pretty damn tough to fool.. however not all markets these engines are sold in requure all the emissions.. mamy of these engines have off-road uses which have much relaxed emissions, or are sold to "emerging markets" where regulations are scarce.. so they can be sold cheaper with none of that equipment.



the computers are the same on them all..


I know there are "people" successful in deleting emissions on Maxxfirce engines making them actually pretty reliable an more powerfull as a result..
-Christopher


You need to be carefull tho. DOT can spot the missing parts if its not done right and has been known to hand out stiff fines. The DPF needs to have the filter removed then reinstalled so it looks original and the EGR pipeing needs to remain as well. I took care of a large fleet of dump trucks and semi's not long ago. The Cummins with the delete kits still cycled exhaust back through the intake so the boost pressure sensor would get caked in soot about every 3 or 4 weeks and would have to be soaked in brake cleaner to clean it. By leaving everything on but the actual DPF, the software didnt need changed. The differential pressure sensors were still in the DPF end caps.

Thats my two cents...

Kinson 03-21-2019 12:51 PM

Bow down to the EPA led by a big-oil CEO or you're a felon.:flowers:

EastCoastCB 03-21-2019 12:54 PM

Quote:

Originally Posted by Bigfoot18 (Post 315436)
You need to be carefull tho. DOT can spot the missing parts if its not done right and has been known to hand out stiff fines. The DPF needs to have the filter removed then reinstalled so it looks original and the EGR pipeing needs to remain as well. I took care of a large fleet of dump trucks and semi's not long ago. The Cummins with the delete kits still cycled exhaust back through the intake so the boost pressure sensor would get caked in soot about every 3 or 4 weeks and would have to be soaked in brake cleaner to clean it. By leaving everything on but the actual DPF, the software didnt need changed. The differential pressure sensors were still in the DPF end caps.

Thats my two cents...

Even on a private vehicle with no DOT #'s?

Bigfoot18 03-21-2019 01:07 PM

Yup. BOW DOWN!


All times are GMT -5. The time now is 08:37 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.