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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Craig R on March 16, 2012, 11:35:41 PM

Title: Can a Deutz engine replace a DD two-stroke?
Post by: Craig R on March 16, 2012, 11:35:41 PM
Could one re-power an MCI MC5c with a Deutz four-stroke V-6 (say a six-cylinder 1015 or 2015) in place of the OE Detroit Diesel 6V71 two stroke? How does direction of rotation effect this project? Would you need to replace the transmission too?
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: Iceni John on March 17, 2012, 12:10:14 AM
Are those the air-cooled ones?   Magirus-Deutz made great engines, but how practical would they be in this country?   Does Iveco have any representation here?

John
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: luvrbus on March 17, 2012, 02:33:43 AM
To long and to wide to replace a 6v71 those are very wide engines somewhere around 50 inches I recall almost 1 ft wider than a 6v71 and they are water cooled, a 6v92 will fit in the same place as 6v71 easier swap the dropbox and angle on a 5 limits you a great deal with what can be done  
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: TomC on March 17, 2012, 08:32:19 AM
On an inline or T drive like the 5, the rotation of the engine is the same as a truck (think of the engine/transmission just rotated around the axle to face backwards).  The external dimensions of the 6V-71 are identical to the 6V-92 (unlike the 8V-71 to 8V-92-the 8V-92 has a big front vibration dampner).  The two main things you'll have to contend with the swap is to increase your radiators, and find a place for the turbocharger with plumbing.  But-the increase in power is dramatic.  The 6V-71 will put out around 225hp at 600lb/ft torque.  The 6V-92TA with 90 injectors will put out 350hp @ 2,300rpm with 1,000lb/ft torque.  Makes a real hot rod out of the 5.  Good Luck, TomC
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: Craig R on March 17, 2012, 10:58:37 AM
So, now my curiosity flys off in another direction! What does anybody know about the DD 6V-92TA methonol engine? Alternatively, how about natural gas conversion of a 6V-71 or 6V-92? Would that be LNG or CNG? Thanks, all.
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: Iceni John on March 17, 2012, 11:10:15 AM
Some Crown Super IIs came with methanol 6V92TAs, but they were all soon converted/repowered with diesel 6V92TACs.   (My Super II was diesel from the start.)   This methanol experiment was to comply with some arcane California emissions legislation, and the school districts bought them with substantial grants.   Some of Rialto's Super IIs were methanol, and they had a second fuel tank to compensate for methanol's worse fuel economy.   I think they also had some sort of fuel cooler as well  -  they still have extra vents on their sides that are not for an AC system.   My Service Manual has electrical schematics for the methanol versions, and there's a lot more wiring and complexity with those buses.

Here's what I found about this short-lived experiment:
http://papers.sae.org/902223/ (http://papers.sae.org/902223/)
http://www.venturausd.org/transportation/id110.htm (http://www.venturausd.org/transportation/id110.htm)
http://www.flickr.com/photos/jfs1988/5691603266/#in/photostream/ (http://www.flickr.com/photos/jfs1988/5691603266/#in/photostream/)

More to the point, where are you going to find methanol these days?!   Maybe a drag strip?

John
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: TomC on March 17, 2012, 11:23:30 AM
The methanol 6V-92TA was a big maintenance nightmare-mainly because they were operating it on Diesel cycle.  You could make a dual fuel out of the 6V-92TA-but it would have to be an electronic or DDEC engine since the engine idles on Diesel then accelerates on natural gas.  But-just like the big rig trucks (I am a new truck salesman for Los Angeles Freightliner) there isn't enough natural gas stations around-whether it be compressed or liquified to make it feasible for RV use.  Believe me when I say-you DON'T want to use natural gas-it is a big pain in the butt.  For in city buses, trash trucks, school buses in big fleets that have lots of extra money for maintenance-natural gas works great.  For attempting cross country use, natural gas just doesn't have the infrastructure yet-I'm betting in the next 10 years it will though.

Currently-the only 100% natural gas engine for trucks/buses (using spark plugs) is the Cummins ISL/G putting out 320hp and 1000lb/ft torque.  18,000mi oil changes, 36,000mi spark plug changes at about $500.00 a pop.  Cummins is coming out with the 11.9 liter in dedicated Natural Gas-putting out around 400hp and 1450lb/ft torque.  Natural gas engines do not have a Jake Brake.

Liquified natural gas is at around 230 degrees below zero.  Even in the insulated tanks, the liquid is constantly boiling.  At around 170psi pressure, the tank releases its pressure to the atmosphere down to a safe 150psi. If you let a truck/bus with liquified natural gas sit for 2 weeks, all the gas will be blown out.  With compressed-the tanks are compressed to 3,500psi. If you do a fast fill (like in 15 minutes) the tanks heat up.  Even though it shows you have 3,500psi, when the tanks cool down, you'll only have about a 3/4 fill.  Most CNG fleets use an overnight slow fill to get full fills since a slow fill won't heat the tanks.

Just stay with Diesel now.  If you think Diesel is expensive to work on, wait till you get into Natural gas.  The liquified gas tanks that are 85gal are about $23,000.00.  The compressed natural gas tanks are about $26,000.00 and have a 20 year life.  Good Luck, TomC
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: Craig R on March 17, 2012, 07:29:56 PM
Thanks, guys! I just keep asking dumb questions and getting smart answers.
My little head is not yet full regarding the Deutz engines. I'm still thinking about a four stroke and anything but a vee is too tall. It seems like I could accomodate a wider engine more easily than a taller one -- but "longer" is a whole nother matter.
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: bevans6 on March 18, 2012, 05:36:29 AM
I once did very careful measuring and an S50 will fit into an MC-5C.  About a half inch clearance on top so I have to say that valve adjustments might be a problem...  But the other side of the coin is that the S50 has far lower cooling requirements.  You could easily do away with the big scroll fans and regain the vertical clearance by modifying the upper deck in the engine compartment.  Some of the guys with S50 in their MC-9's are using just one of the stock radiators.

With a 6V92 you will be able to use the same engine cradle and bellhousing mounts as you currently have with the 6V71.  The normal 6V92 mounts the turbo on top of the engine and you will have to either move it to one side or eliminate the stock fan drive system.  People have done both, using a hydraulic motor for the fans. 

Brian
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: Mex-Busnut on March 18, 2012, 05:40:38 AM
Iceni John:

Excuse my ignorance. What does the C on the end of your 6V92TAC stand for? Computerized maybe? I know the TA is Turbo Aspirated.

Thanks in advance!
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: luvrbus on March 18, 2012, 05:43:31 AM
After cooled engine not aspirated TA or TAC as some say fwiw
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: TomC on March 18, 2012, 09:13:02 AM
TA=Turbocharged Aftercooled; TAC=Turbocharged Aftercooled California.  Should stay away from the California version-while cleaner burning, uses more fuel (retarded timing).  Good Luck, TomC
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: Mex-Busnut on March 18, 2012, 04:45:30 PM
Thanks for educating me, friends!
Title: Re: Can a Deutz engine replace a DD two-stroke?
Post by: Iceni John on March 18, 2012, 05:55:58 PM
Yup, mine's the Californicated version, with a sunnier disposition and healthy organic free-range macrobiotic exhaust.   Could its timing be advanced (unretarded?} to give better fuel economy?

John