Engine power question?
 

Engine power question?

Started by 5B Steve, March 15, 2011, 04:41:12 PM

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5B Steve


  I have a 1975 MCI-B 8V92N, On my trip to Daytona Beach, FL for bike week south of Nashville, TN. the engine

  seemed to come to "LIFE." The power was totally stronger than when I left Indianapolis. It climbed Monteagle

like it wasn't there, never downshifted right on up.  This is a STUPIED question to ask, has anyone ever had

this happen or is this just my imagination?  The engine has always been meticulously maintained. I have only

put 5,849 miles on the bus in the last 7 years,1,994 of those in the last two weeks round trip. The engine has

29,000 plus miles on a rebuild!  Thanks for any impute.

    Steve 5B.....

busnut104

I had a 8V71 in a dump truck which did that ran like the wind for a coupl hundred of miles  and then she blowed, spun a bearing oil all over the place.

chart1

I don't think that was what steve wanted to hear!! >:( >:(LOL
1976 MCI 8
8v71/740auto
8" roof raise

boxcarOkie

Quote from: chart1 on March 15, 2011, 05:22:34 PM
I don't think that was what steve wanted to hear!! >:( >:(LOL

Oh no, say it isn't so!  Y'know how a light bulb has that huge intense flash of light before it crashes and goes out for the last time?  They have a name for it ... Maximum Effort.  Maybe that is what is happening here?

BCO

Jeremy

Sounds like a classic case of Italian tuning


Jeremy
A shameless plug for my business - visit www.magazineexchange.co.uk for back issue magazines - thousands of titles covering cars, motorbikes, aircraft, railways, boats, modelling etc. You'll find lots of interest, although not much covering American buses sadly.

white-eagle

you all are no help!!  the guy asked a semi-serious question.

i've had instances where it suddenly seemed to run better, like a dragging brake that just freed up, or it got some uncontaminated air.  somebody told me cool air works better in the engine intake?  anyway, i have had times when the horses seemed a little more strong, and it climbed right up a hill.

knock on wood, has not blown up or burn black smoke and the mileage is still good, etc.

by the way, we did start pulling the engine today - to cure the oil leak.  the engine ran fine before i got here, and i'm sure it will run better when i leave.
Tom
1991 Eagle 15 and proud of it.
8V92T, 740, Fulltime working on the road.

Fran was called to a higher duty 12/16/13. I lost my life navigator.

Van

Oh that! Always happens when they know the destination is Daytona, besides it's all down hill lol. Sounds like it was just blowing out the cobb webs ;)

   Van
B&B CoachWorks
Bus Shop Mafia.
Now in N. Cakalaki

fe2_o3

Finally broke it in...Cable (that's my story and I'm sticking to it.)
Sofar Sogood
1953-4104
KB7LJR
Everett, WA.

DMoedave

did you add any new fuel ? I like the dragging brake theory .
we love our buses!!! NE Pa or LI NY, or somewhere in between!

artvonne

  Anytime a dramatic change occures, you would be wise to do some investigating. Did it really gain power, or was the power being restricted all long?

  My guess is its probably fuel related, but why it would be so sudden after 7 years seems a bit odd. If its turbo'ed, extra power could come from a blocked wastegate.

  Engines of any one particular design will only make the power they are designed for, within a very small range. Its vitually impossible for an engine to suddenly make more power without added fuel, or a cylinder that was losing compression to "wake up". Perhaps you had an injector that was partially plugged and didnt know it?

TomC

If it was in the 50 degree weather and a bit damp-Diesels love that kind of weather.  Maybe just the right weather, a little hotter fuel, maybe a bit more accelerator travel, etc.  You have a rare engine-not many 8V-92NA made.  Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

wal1809

I have noticed in the hot summers hear in Texas my 6v92 is a bit more sluggish than on cooler winter temps.  The temps really pep the motor up.  I notice that in all my vehicles though.
1984 Silver Eagle Model 10 6V92 Allison auto tranny
www.snakebreaker.com

bevans6

I actually find that happens all the time to me, and it's me, my driving and my perceptions that change.  the first day of a long trip I am slow on the gas, too early on the brake, I don't carry speed into hills or curves instinctively, and the bus doesn't perform well.  After I'm completely acclimatized to the bus I just drive it better and my expectations have come in line with the bus capability and I am a lot happier with what's going on.  Not to mention that you probably had some of your fancy additives in there waking it up, everything loosened up after not running hard for so long, the engine probably  was woken up by the trip.

Brian
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

5B Steve


  Thanks guys! for all your impute. Like I formentioned this was the longest trip that I had made since I

  purchased the bus several years back. Maybe indeed it needed to be run like it was designed for. The

  results were satisfying. ''WHAT WAS AMAZING IS THE FACT IT JUST SIPPED FUEL." With the currant

  fuel prices, I cringe also, but the way the performance was more long trips are in the making!

  Once again, thanks for all your response.

   Steve 5B..........

Oonrahnjay

Quote from: busnut104 on March 15, 2011, 05:00:20 PMI had a 8V71 in a dump truck which did that ran like the wind for a coupl hundred of miles  and then she blowed, spun a bearing oil all over the place.


It was the fastest I ever goed, then I fell off"   Little Fauss, 1969
Bruce H; Wallace (near Wilmington) NC
1976 Daimler (British) Double-Decker Bus; 34' long

(New Email -- brucebearnc@ (theGoogle gmail place) .com)