The ISM hit the road! -- Update

[Brian Diehl]

Well, I had a Cummins mobile tech come out and take a look at the engine computer.  It turns out some of the "features" defaulted to some very bizarre values.  One of the problem values was "Maximum switched engine speed", which had a value of 1205.  So, the tech simply upped the value and wala, the engine now revs correctly!  I had the tech set some of my other features/parameters as well.  The computer also indicates that the engine has already been reprogrammed to its maximum 450hp setting. (sweet!)

Before the tech left he says "so, you want to take it for a drive so I can make sure no other fault codes come up while we are moving"?  I of course said "Sure!".  So, I disconnected shore power and took off down the drive way.  Imagine my complete surprise when the tranny (Eaton Autoshift) was already in 3rd by the end of the driveway!  Wow, it works! I can't believe it did autoshifting like it was supposed to!  I mean, all that work over the past 5 months and my wiring was correct on the very first try.  SWEET!  Man, I'm so excited now I almost forgot to slow down for the end of the driveway to make the turn onto the street!  We went around the short block and the tranny performed flawlessly.  It is in 5th gear before 20mph and all shifts are supper smooth and fast.

We stop in front of the house again and the mobile tech finishes setting some other parameters for me like my diff gears and tire rotations/mile.  Then, he offers to ride again while we make sure all the final changes are okay with no new codes being set in the computer.  So, off we go for a 3 mile loop. We speed up and high range is selected with no fanfare (5-6 gear change).  Then stop for a stop sign.  The next shift from low range to high range "hunts".  The next stop light and as we accelerate the tranny gets hung up between high and low range and we drift to a stop.  I try all kinds of things to get it out of "no mans" land, but no luck.  Then in a moment of genius (my own delusion!) I decide to pump down the air tanks.  Dumping the air does the trick and after building my air pressure back up again the tranny is happy to go back in 1st.  Start going and it hangs up again between 5th and 6th.  Dump my air pressure and restart....  Then I decide to not allow the tranny to go to high range and stay in 5th all the way back home.  Boy, 5th sure is slow --- about 23 mph at 2200rpm! 

So, tonight I tear apart the range select valve and cylinder assembly to find out why it is getting hung up.  I have a bad air leak out of the range select valve and I think if I solve that air leak the range split shift should work correctly again.

Of course, after all that I had a hard time going to sleep last night.  What an exciting day after all that hard work to have it run the way it is supposed to.  Those Jake Brakes are cool too! 

Now, due to so many shifts before 20mph it is a little slow off the line.  Each shift is fast, but there are still a lot of shifts.  Get it up into 6th and higher and put the foot into the throttle and you can really feel the engine come alive.  Wow, does it accelerate fast!  I can't believe how different that 4-stroke behaves from the old 6v92.  It sounds different, accelerates like nothing I've ever experienced and cruises along at 1200 rpms!  The one time I had high range without problems I hit 43 mph and the tranny was running in 9th gear with the engine loping along at 1200rpms.  It was not lugging at all and when I put my foot into it just a little you could feel the jolt in the backside as it poured on the power.  Gotta get that high range valve working right so I can get on the freeway and see how it handles the hills!

[H3Jim]

that's exciting.  Great to hear of you success and that its finally working.  Keep us posted

[rv_safetyman]

Hi Brian.  Obviously, I can relate to every word you presented!!!!

As you probably know, the transmission will "learn" what gear you want to start in.  I start in 2nd, but could start in 3rd most of the time.

You can also skip gears by putting the control in the hold position and hit the upshift button twice for each gear change.  I don't do that very often, as I like to hear the bus go through all of the gears.

No matter what you do, the acceleration will be a bit slow. With each gear change, you will need to build boost again.  That takes a couple of seconds and that all adds up.  I consider the somewhat slow acceleration to be acceptable.  I am over 42K pounds with the Durango and full fluids.  I figure that, with that much weight, I won't be a jack rabbit under any circumstance.

[Buffalo SpaceShip]

Exciting indeed, Brian! Hopefully the split shift issues are just the air leak.

Your engine/trans sounds like an amazing combo for a bus. Most of us are stuck with just a few gears and a narrow power/ torque range.

Thanks for the update, and many happy "bus thoughts" sent your way on the repair,
Brian B.

p.s.
Assuming you fix your range issues, are there any plans for a nice long shakedown trip this Fall??? Love to hear how she does out on the open road!

[TomC]

I would advise just to change out the range cylinder, not that pricey.  It's exciting when things work correctly the first time.  This last weekend, I installed both a tachometer and a new fuel tank sending unit (had to cut a hole in the floor) and both worked correctly the first time.
On driving the autoshift, as previously mentioned you can skip shift for a faster acceleration.  Put it in the manual mode-rev it to the governor and when you want to shift just hit the up buttom twice (you'll learn the speed of which it likes).
What rear end gearing do you have?  Based on 43mph at 1200rpm in 9th, you should have 75mph at 2100rpm in 9th!  So in 10th at 75mph you should have a nice cruise of 1550rpm.  Sounds to me like just about perfect gearing.  Glad to hear it's working out well.  Good Luck, TomC

[Brian Diehl]

Thanks guys for the well wishes!

Jim, I'll get those crimpers out to you in the mail soon ...

Brian, I'd love to do a long cruise, but I'll work up the miles gradually until I know I'm going to be issue free.  I'll start with around the block a few times to make sure high range works consistently every time.  Then a short freeway stint.  After that a longer freeway loop and then a real long loop all around the twin cities here.  If that works out great I'll move on to a drive up to Duluth or equivalent for a Weekend day.  Once I'm up to a couple hundred miles without issues I'll look to plan a longer trip.  Gotta work up to these things!  :-)

Thanks for the idea Tom.  I'm tearing it apart this evening, so I'll see what I find once I have it off and on the bench.

[Busted Knuckle]

Sounds like you need to be getting those cruises in! The BK's Bus Bash in TN is Sept. 6-10th! LOL! Come on down! We gonna have fun! And it will not be exclusive too (or from)Brians! LOL!
Glad to hear it's working out! Maybe you could be our Guest speaker on power swaps! LOL!
  BK 

[Bob Belter]

Ahoy, Brian,

Congrats on getting underway with your Autoshift. 

My M-11 Select Cummins in my -01 Eagle is tied into a ten speed Roadranger RTO1110 overdrive, and the combo works great.  However, my 32,000 mile (perfect) engine does NOT have the J1939 protocol connector, and it cannot be changed over.  Hence, NO Autoshift for me.  I'd love to do one.

Enjoy /s/ Bob   

[Brian Diehl]

Oh yeah Tom, I have the 3.33 diff in my bus....

[Brian Diehl]

Turned out to be a simple fix.  I tore apart the range valve and found a bunch of crud in the high range selector air ports.  There was enough rocks in the air ports to completely block the air flow.  A good clean out job and put everything back together was the ticket.  It now shifts smoothly and quickly into and out of high range.  My air leak is even gone as well!   I've now got about 40 miles on the repower.  Nice to have the tranny shifting good.  Now I need to deal with my turbo charger .... --- in another post.