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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Fredward on October 22, 2007, 07:01:18 AM

Title: MCI-5A Engine Mount angle
Post by: Fredward on October 22, 2007, 07:01:18 AM
Why is the engine and transmission mounted at an angle to the rear axle? I thought the "T" drive was at 90 degrees? My engine and transmission is canted slightly to the curb side of the coach.
Fred
Title: Re: MCI-5A Engine Mount angle
Post by: Stan on October 22, 2007, 11:51:03 AM
In a MC-5 there is not enough length between the rear bumper and the drive axle for a 8V71 DD and a transmission plus a drive shaft into a differential. The solution was to mount the differential facing forward with a drop box containing two gears that raise the height of the pinion above the level of the axle housing. The driveshaft can then go from the transmission over the axle housing beside the large housing for the differential. It would not be possible to put the driveshaft over the top of the differential housing keping everything in a straight line, parallel to the coach.

The same problem existed for the 35' Gm coaches which they solved by mounting the engine crossways.
Title: Re: MCI-5A Engine Mount angle
Post by: tekebird on October 22, 2007, 12:18:46 PM
Gm coaches have the Engine Transverse by design not necessity.

the purpose was ease of maint.

side note, the rear bumper to axle distance on a 35  foot GM is the same on a 40 foot.

the 40 foot GM's had a boggie axle (optional) in front of the drivers
Title: Re: MCI-5A Engine Mount angle
Post by: kyle4501 on October 22, 2007, 01:09:58 PM
Quote from: tekebird on October 22, 2007, 12:18:46 PM
Gm coaches have the Engine Transverse by design not necessity.

the purpose was ease of maint.

side note, the rear bumper to axle distance on a 35  foot GM is the same on a 40 foot.

the 40 foot GM's had a boggie axle (optional) in front of the drivers

Not ALL 40' GMs   ;)

The compact drive train on most GM's increased bagage space which allowed for higher revenus for package hauling.

A win win solution.
Title: Re: MCI-5A Engine Mount angle
Post by: Stan on October 22, 2007, 01:27:26 PM
tekebird: I have seen 35' GM buses with an extended rear and a T drive. Is there enough length to put in a T drive straight into the differential? The rear axle location looks to be about the same on MCI and GM.
Title: Re: MCI-5A Engine Mount angle
Post by: Fredward on October 23, 2007, 06:05:55 PM
Thanks Stan. I was getting tired of explaining to my buddies why the engine in my coach was at an angle. They all want to help me straighten it. When you live in a farming community everybody has great ideas.
Fred