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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: george_barb on June 14, 2011, 05:50:02 PM

Title: 6V92 Question
Post by: george_barb on June 14, 2011, 05:50:02 PM
Seen advertised 2008, 6V92 with an allison transmission out of a firetruck.  Would this work in a MC9?  If so, how well?  Also, is there such a thing as a 2008, 6V92?  Opinions please!  Thanks, George.
Title: Re: 6V92 Question
Post by: luvrbus on June 14, 2011, 06:14:03 PM
It will work but it takes a lot to make it work everything on the rear has to be changed and if it doesn't have the gear driven alternator you need to tear the engine down and install the camshaft on the right side for the alternator (looking from the rear)

You can buy a brand new crate 6v92 today close to 30 grand I was told by WW Williams not rebuilt new 2011
Title: Re: 6V92 Question
Post by: bevans6 on June 14, 2011, 06:20:35 PM
You also have to change everything on the front to put the MCI front cover on so the motor mount has something to mount to.  You may have to change the thermostat housings and the water fittings on the front of the heads.  Plus the fuel plumbing.  Ask me exactly how much you have to take off, clean, paint, and put back on, I've just done it.  I bet 50 hours if you started and did nothing else 10 hours a day and you had all the parts and the gaskets.  That may be a low estimate... I have around 150 hours in my project so far!

Brian
Title: Re: 6V92 Question
Post by: luvrbus on June 14, 2011, 06:31:40 PM
You don't have change anything on the front of 6v92 from a fire truck maybe the 2 little brackets for the front mounts I think the firetrucks use the bottom type mounts not much to change up front Brian it is not a industrial or military engine but as you well know the back is a PITA and more if he needs the camshaft as most of truck engines are belt driven alternators only the bus manufactures were dumb enough to install a gear driven alternator lol

good luck
Title: Re: 6V92 Question
Post by: bevans6 on June 14, 2011, 06:55:17 PM
MCI, at least my MCI, uses a unique, MCI specific round thing in the middle of the front gear cover for the cradle mount, which means taking the front off, at least the water pump and the gear cover.  You only have to take the cam gears and the front plate off if you have to change the water fixtures that bolt to the heads.  I had to go to the block front and rear.  I am just about to put the transmission back on, just about exactly 6 months after I took it off...  Just farting around with the clutch linkage...  Always something.  some dufus cross-threaded a rod end in the clutch linkage and decided "It's cross-threaded, it won't move, I'll leave it even though it's adjusted totally wrong, no one will notice the pedal pressure is twice what it should be..."

The only saving grace is the bit that's ruined from being cross-threaded is the rod-end, which is the bit that you would throw away and change anyway if you were going  to rebuild such a thing correctly in the first place.  So I will drive out to the rod end store and buy a couple of new ones tomorrow.  Such is the life of a bus nut...
Title: Re: 6V92 Question
Post by: george_barb on June 14, 2011, 07:05:19 PM
Thanks for your opinions thus far.  What do you think of the transmission from a fire truck, still on the motor, it's an allison.  Don't know much info on it, haven't seen it.  Haven't talked with owner yet.  Thinking of it for a spare unit.

George
Title: Re: 6V92 Question
Post by: luvrbus on June 14, 2011, 07:09:15 PM
Brian, that is a 71 series setup not a MCI Eagles had the same setup with the 8v71 a 92 series can have it also but it is not part of the housing it bolts to the block only

good luck
Title: Re: 6V92 Question
Post by: NJT5047 on June 14, 2011, 07:15:30 PM
Firetrucks can make great donors, but they need to be checked carefully for issues.  They spend their life being fired up and immediately run against the gov.  Fortunately, most fire trucks are kept on block heaters.  
I have no idea what the mileage/hour conversion would be for a firetruck, but 5000 "firetruck" miles might equal the wear of a 200K OTR engine.   Might not too.  Might be a great deal.   Service history and bill showing actual purchase of the engine would be a good incentive.  Fire stations generally keep good maint records.  
As has been said, changing the bell housing and accessories is a giant PITA...but if you buy a rebuild, the bell housing will still haveto be done.  Either way, the bell housing is coming off unless you buy a bus take-out.
If you have a nice conversion, and plan to keep it, install a 4 stroke.  That's a lotta work too, but you'll like the end result.   One thing's for sure, I wouldn't pull a good running 2 stroke without reason.   Has your engine failed?
Good luck!  JR  

Title: Re: 6V92 Question
Post by: luvrbus on June 14, 2011, 07:48:04 PM
To add to JR it better be from a MCI if going in a MCI I just changed a Eagle takeout to a MCI too damn much work for me 

good luck
Title: Re: 6V92 Question
Post by: george_barb on June 15, 2011, 07:14:15 AM
JR:  our engine has not failed, still running good.  It's an 8V71 with maybe 6-700,000 miles and just looking ahead and thinking of spares.  Owner to return call and will get more info. 

George
Title: Yep!...Check The Vehicle History Carefully
Post by: HB of CJ on June 15, 2011, 11:13:04 AM
Did the fire apparatus manufactures even install 2 stroke Detroits in 2008?......or is the fire engine much older with an older 2 stroke
Detroit installed in 2008?  Or....is it even something even weirder?  Dunno.

There must be some good reason they are selling such a "new" engine.  Cracked frame, busted fire pump.... unfixable collision damage?  The mill and tranny might be in good shape.  Road mileage is a poor way to determine fire apparatus condition.

Do more research.  Do they have an hours of service report on the engine and pump?  Oil analysis?  Etc..  Might be one heck of a deal....or a hanger queen due for the crusher.  HB of Cj (old coot)  (retired fire service) (class 1 dept.)
Title: Re: 6V92 Question
Post by: NJT5047 on June 15, 2011, 07:06:52 PM
I'd bet that the truck and engine are much older than advertised....just a bet mind you.
Fire trucks wear out in odd ways...tanks (which form almost an integral part of the chassis) rust out, pumps made of unobtainium fail, frames and cab structures fail.  They just are not worth repairing. 
The year model of the engine can be determined with the numbers...as could the year of the apparatus.   
There are a good many really neat looking firetrucks offered all the time.  But, they more often than not have major issues.  That said, the engines and transmissions might well be a nice item.   Just have to evaluate the thing. 
A good 350 HP fire truck engine would make a much better powerplant than an 8V71N.   
A fire truck 6V92TA could be a 400 HP engine, which might be a problem to cool in an MCI.   
Good luck, JR
Title: Re: 6V92 Question
Post by: george_barb on June 16, 2011, 02:23:47 PM
Spoke with the owner, he never ran it so doesn't know too much about a detroit, 2 stroke, but the year 2008 turned out to be 80-84, misprint.  Doesn't know if it has a turbo.  Thinks it's 4 speed automatic, 77000 klms, (46000 miles approx.)   It is complete mounted in the frame with front axle, he just cut the frame off behind the transmission.  Don't know whether to go for it at $1500.00 or let it go.  What do you guys think, would it have a turbo?  Thanks in advance.

George
Title: Re: 6V92 Question
Post by: TomC on June 16, 2011, 02:26:20 PM
Most likely will have a turbo. Very rare to find a non turbo 92 series in a truck.  Good Luck, TomC
Title: Re: 6V92 Question
Post by: luvrbus on June 16, 2011, 02:33:01 PM
Check the serial number the 6v92 Silver engine came out 1982 anything below this serial number forget it F83425


good luck
Title: Re: 6V92 Question
Post by: NJT5047 on June 16, 2011, 08:24:43 PM
Most likely if there's no turbo, it's been removed.  The turbo might be mounted low on either end of the engine, or high mounted on the blower,  The blower high mount is correct for an MCI.  The owner either doesn't have a clue, or he's trying to hook a sucker.  Whatever, the picture isn't good.   As TomC sez, OTR V92 series had turbos.   
Stationary engines (generators or oil field pump motors) would be the only thing in a V92 non-turbo.  And it ain't that. 
Another way to rule the engine out is to dig through the layers of paint...if you find 'Alpine Green' as the base color, walk away.   
The transmission is very likely an Allison HT740, 4 speed.  But that oughta be verified too. 
If you cannot run the engine and verify the condition, I'd walk.  If it's been sitting around for years, it really should be freshened up before trying to use it.  It isn't worth "freshening up"....
Not enough info to make a decision...yet. 
JR
Title: Oh Boy....Might Be Best To Pass And Why....IMOHO
Post by: HB of CJ on June 17, 2011, 10:36:13 AM
Seller must be responsible for providing accurate and timely info....if he is secure with what he is selling.  Too many unswered questions for my taste; FWIW.  (HB of CJ)
Title: Re: 6V92 Question
Post by: Carcrazyguy57 on June 21, 2011, 10:50:19 PM
Second hand info, for what its worth. Fire truck engines have the governor set to about 2500 rpm, and when they get rid of them they are pretty much cooked.
Title: Re: 6V92 Question
Post by: artvonne on June 22, 2011, 02:58:30 AM
Quote from: Carcrazyguy57 on June 21, 2011, 10:50:19 PM
Second hand info, for what its worth. Fire truck engines have the governor set to about 2500 rpm, and when they get rid of them they are pretty much cooked.

  I would second this. Fire depts dont get rid of good working equipment. Once they start having issues with stuff they pass it downstream to smaller fire units until no one wants it. There are tons of MC9's for sale right now, many at scrap price and less and most ride and drive. You could quite easily find a less than pretty one with good running gear, take what you want, and either give away whats left or possibly even get someone to come and get it and pay you for the trouble.

  Unless your mechanically inclined and can adequately verify what your looking at as well as its condition, I would stay away from it. Even then, if you cant start it or otherwise test it, dont pay much more than scrap/core price for it.