speed governor- (not wife)
 

speed governor- (not wife)

Started by ttomas, August 23, 2007, 04:11:12 PM

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ttomas

Is there a speed governor in addition to a rpm governor on a  mc9- 6v92ta / 740 trans? If so, can I adjust it to go faster down hill?  Thanks Tomas

Hartley

Yeah, It's that stream of parts following you down the hill when you overwind the engine.

You really don't want to overrev a detroit too much. they degrade rapidly above 2,400 rpm and start breaking down internally and will eventually lose seals, sleeves and other parts. They can't run at 5,000 rpm like your honda.....

Seriously... Having 30,000 lbs of out of control bus screaming down a hill just scares the jeebers outta me... I almost had that happen a couple of months ago... Lucky I have a Jersey 9 with better brakes!!!

Dave..... Want real fun, Try Hwy I27 across Signal Mountain Tennessee... Parachutes Optional!!
Never take a knife to a gunfight!

Dallas

As you reach the top of the hill, close your eyes, put the bus in Georgia Overdrive, hang on and GO!

Just make sure I'm no where around when you do it.

Dallas

RJ

Quote from: ttomas on August 23, 2007, 04:11:12 PM
Is there a speed governor in addition to a rpm governor on a  mc9- 6v92ta / 740 trans? If so, can I adjust it to go faster down hill?  Thanks Tomas

Why???
1992 Prevost XL Vantaré Conversion M1001907 8V92T/HT-755 (DDEC/ATEC)
2003 VW Jetta TDI Sportwagon "Towed"
Cheney WA (when home)

Busted Knuckle

Quote from: Russ on August 23, 2007, 06:10:31 PM
Quote from: ttomas on August 23, 2007, 04:11:12 PM
Is there a speed governor in addition to a rpm governor on a  mc9- 6v92ta / 740 trans? If so, can I adjust it to go faster down hill?  Thanks Tomas

Why???

That's simple Russ! To be the first one down the hill! LOL! ;D  BK  ;D
Busted Knuckle aka Bryce Gaston
KY Lakeside Travel's Busted Knuckle Garage
Huntingdon, TN 12 minutes N of I-40 @ exit 108
www.kylakesidetravel.net

;D Keep SMILING it makes people wonder what yer up to! ;D (at least thats what momma always told me! ;D)

RJ

BK -

You mean to be the first one at the accident site, right?

:o
1992 Prevost XL Vantaré Conversion M1001907 8V92T/HT-755 (DDEC/ATEC)
2003 VW Jetta TDI Sportwagon "Towed"
Cheney WA (when home)

ttomas

thanks guys, I knew I was going to catch it from you. 74 mph is definitely fast enough. that is my downhill top end. I have trouble topping  the next hill at 35. my last 210 hp cummins school bus did way better. Is this normal?  Tomas

Dallas

Tomas,

Considering that your MC9 weighs 15,000 pounds more than your skoolie, that's not too bad. Your 6V92TA can be turned up to put out more torque and HP (350?) if it's still in the factory configuration.
The only thing going downhill faster will get you is a ride in a helicopter.... to the hospital... if you survive.

There are also other things you can do to help get up the hill faster.
When was the last time you checked the air intake?
Air Filter?
Do you manually downshift your HT740 before you start dropping RPM's? If you are blowing smoke as you go up the hill, your wasting fuel and horse power. Keep the RPM's up in the power range. Don't let the transmission decide when to shift... it's kind of stupid and doesn't really care what the engine says.
When was the last time the rack was run in that engine?

Good luck and if you decide to drop off Cabbage, Snowbird, Grapevine, Lolo, Pipestone, Monteagle or any other big hills in neutral, let me know ahead of time so I can wake up Cat.
I want to wake her up 'cause she ain't never seen a wreck like this ones gonna be! ::)

Dallas

ttomas

Thanks Dallas,  I was not aware that I should override the auto shift.that should help. I have only driven the bus 800 miles, and that was when I bought it. I changed  all filters when I got home. This helped. Yestereday I found a clogged up Catalytic converter. This was probably my problem. My 40' Thomas bus weighed in at 30,500lbs.. Hopefully the mc9 is not 45k
thanks for the picture. point well taken. tomas

maria-n-skip

Dallas,

   Nice blast from the past. Was the pic taken in the early 50's?

    Lolo, Pipestone....If you were referring to the Montana ones we have worse
and so does the rest of the rocky mountain range.  For those of you liking to travel state
higways instead of  Interstate please be careful at 30k+lbs speeds build up fast and when the sign
says curve 35mph I always make sure I'm at 25mph. Not so many white knuckles
when done. Speed limits are mostly set for the normal vehicle not heavies it is assumed
that heavies are driven by professionals and they should know the value of keeping their speed
safe and reasonable.
   FWIW
  Skip

H3Jim

In the bus I have found that I can comfortably take most corners at the posted speed.  Thats without shifting things on my shelves, or doing any uncomfortable leaning.

When I was younger and in a car I found that could take most corners at almost twice the posted speed.  Hope there's not more like me out there.
Jim Stewart
El Cajon, Ca.  (San Diego area)

Travel is more than the seeing of sights, it is a change that goes on, deep  and permanent, in the ideas of living.

Dallas

Quote from: maria-n-skip on August 24, 2007, 07:02:32 AM
Dallas,

   Nice blast from the past. Was the pic taken in the early 50's?

    Lolo, Pipestone....If you were referring to the Montana ones we have worse
and so does the rest of the rocky mountain range.  For those of you liking to travel state
higways instead of  Interstate please be careful at 30k+lbs speeds build up fast and when the sign
says curve 35mph I always make sure I'm at 25mph. Not so many white knuckles
when done. Speed limits are mostly set for the normal vehicle not heavies it is assumed
that heavies are driven by professionals and they should know the value of keeping their speed
safe and reasonable.
   FWIW
  Skip


Skip,

The picture is from 1948 and use to be a school bus. I forget what kind.

Yes, I was talking about Montana, Idaho, California, Oregon and Idaho. Those were the places I was mostly raised in. We had a logging company when I was young and I learned to drive on a 1941 A-40 model Mack with a flathead 6 cylinder engine, single axle, air over hydraulic brakes, a 4 speed main transmission, 3 speed aux. and a 3 speed truck transmission turned backwards to give us granny-granny-low-low. We needed it since we pulled log trailers with 60K pounds of lodge pole pine down the same roads the guys with the BIG trucks used.
I felt like one of the big boys when my step dad bought a 1963 needle nosed KW with a 250 cummins and a 5X4 two stick transmission.

Dallas

maria-n-skip


Jim & Dallas,

   Both you old boys know this part of the country well and have the experience to back it.
You would be surprised on the number of Flat landers (no disrespect intended)
I see hitting the brakes at the apex of a curve coming down a pass. Knowing a road and experience in the rig
gives one a lot of latitude at what speeds one goes down a pass.


Skip

HB of CJ

Sounds like (maybe?) you have a mechanical Detroit, along with the earlier 740.  But then again maybe not.  Going down a hill very fast would overwhelm any governor, speed limiter or engine brake.

Gravity really sucks really.  You would reach a point where it would be practically impossible to stop the coach in a reasonable fashion, except to decelerate really fast and hard hitting a mountain.

The Grapevine is not a pussycat.  Many times I went North and South, first with a now old , newer then Crown school bus full of kids, then later hauling product (gas) from Bakersfield to Terminal Island.

Coming down empty North with the school bus, the old girl would hang right at 40-45 mph riding the Jake all the way down.  With the tanker full of gas, right at 18 to 20 mph both ways, again on the Jake,...

...with regular service brake applications.  Do remember once a "runaway" came flying past North with flames coming from the tires and wheels.  It crashed rather badly.  Guess the tires finally exploded.

An ongoing problem seems to be ordinary folks buying these huge nice motorcoaches and still thinking  they can drive the beasts just like their cars.  Bad idea.  Life is too short. Thanks. :) :)

DrivingMissLazy

I recall a poster recently (who shall go unnamed) that was apparently not knowledgeable about the requirement to gear down when coming down long grades. He got somewhat indignant when it was suggested he go to northern California a get Russ to give some driving lessons on a bus. LOL
Richard


Quote from: HB of CJ on August 24, 2007, 01:45:08 PM
Sounds like (maybe?) you have a mechanical Detroit, along with the earlier 740.  But then again maybe not.  Going down a hill very fast would overwhelm any governor, speed limiter or engine brake.

Gravity really sucks really.  You would reach a point where it would be practically impossible to stop the coach in a reasonable fashion, except to decelerate really fast and hard hitting a mountain.

The Grapevine is not a pussycat.  Many times I went North and South, first with a now old , newer then Crown school bus full of kids, then later hauling product (gas) from Bakersfield to Terminal Island.

Coming down empty North with the school bus, the old girl would hang right at 40-45 mph riding the Jake all the way down.  With the tanker full of gas, right at 18 to 20 mph both ways, again on the Jake,...

...with regular service brake applications.  Do remember once a "runaway" came flying past North with flames coming from the tires and wheels.  It crashed rather badly.  Guess the tires finally exploded.

An ongoing problem seems to be ordinary folks buying these huge nice motorcoaches and still thinking  they can drive the beasts just like their cars.  Bad idea.  Life is too short. Thanks. :) :)
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body. But rather to skid in sideways, chocolate in one hand, a good Reisling in the other, body thoroughly used up, totally worn out and screaming:  WOO HOO, what a ride