8v71 engine and cradle location data MCI 7,8,9

mikelutestanski · January 21, 2008, 06:33:54 PM

Hello:
1: Where is the center of the crankshaft on an 8V71 with respect to the cradle arms?. Is it centered or offset?
I believe it is centered and 1" below the top of the cradle rails. Is this true?

2: Where is the back of the transmission with respect to the rails . Is it centered and 1" below the top of the rails as well?
I believe it is centered and 1" below the top of the rails as well.

Having said that then looking at the differential it is not centered and is offset to the passenger side at least one inch.
3: What is the angle the propeller shaft should make between the differential and the transmission?

Of course in the up down direction that will change depending on the air bags and the road etc; but as a general rule the driveshaft in the normal road position should be level . True?

SO I am soliciting information from those who have experience with this stuff to publish your observations and thoughts.. I am most interested in an MCI 7 but 8s or 9s will or should be the same. THis is a T drive configuration .
The mci 5 will differ and the cradle is offset to allow the driveshaft to go over to the dropbox ..FYI. Not interested in that particular model..
Thank you for reading and commenting.. happy busssin Mike

Tenor · January 21, 2008, 07:04:01 PM

I'm sure someone here has the info, I don't but I'm very curious about what you are working on.

Melbo · January 21, 2008, 09:32:29 PM

I do not have personal experience but have been told that the MC8 is 3 degrees out of square

Melbo

mikelutestanski · January 22, 2008, 06:33:49 AM

Hello: As to the question of what we are working on?::

I decided a few years ago to repower. Having made the decision the best way in my opinion was to buy another bus and use what was necessary.. So we bought a couple of transits Orion 1 buses to utilize the Cummins L10 and B400R transmission. This has a 6 speed tranny with a 4.56 rear double overdrive. So with this we needed to strip one bus and use the tranny wiring and anything else to affect the transfer to our MCI 7
It would have been easier to use a series 50 but when I wanted one none were available in my price range.
So we are in the process of transplanting. The 8v71/740 with cradle is out of the 7 snd the new combo has been rolled into place. we need to finalize the location so work on the cradle and motor mounts can proceed. The differential will be changed to 4.63 and the center of the tag axle needs some modifications to enable the transmission oil cooler hose connections on the rear of the tranny to fit. The retarder on the back of the tranny makes it like a box shorter but more square.
Work is proceeding slowly . thanks for your comments Happy bussin . Mike

Tenor · January 22, 2008, 07:01:47 AM

COOL! Keep us posted with pictures!

Stan · January 22, 2008, 08:09:56 AM

Here is a link to a page on driveline angles that may help you.

http://www.drivetrain.com/driveline_angle_problem.html

JohnEd · January 22, 2008, 04:39:29 PM

Stan,

That site looks like the answer....period. Not just help. Thanks for the great reference.

John