UPDATE 2/17: Shepherd Engine Saga Continues - third drive - about the same

[dickegler]

Jim, just thinking about the trans codes.

  Are there not some instances where the trans ecm can limit the torque in lower gears to protect the drive train?  any chance something like this is happening?

Do you have good acceleration in the low gears?

Good luck, and enjoy the Q

Dick Egler

[rv_safetyman]

Dick, interesting thought. 

I don't think the transmission sets the limit, but I think there is a setting in the DDEC ECM.  I will probably not have a chance to look at that before I leave. 

Acceleration seems OK in 2nd (the first gear I use) and maybe 3rd, but dies after that.

Right now, I know that I need to get the transmission issues resolved before I do any more testing.  Kind of neat, as I have a second complete AutoShift in case I need to do some parts switching. 

Good project for when I get back with my "clear" head

Jim

[larryh]

Jim,

Larry here from Quartzsite I just talked to a friend that is shop foreman and I regard as a guru on the ecm's he said before you will get full boost you must clear up your tranny faultss it's just doing it's job of protecting your engine from the cowboys driving today.

Good Luck

Larry H.

[rv_safetyman]

Larry, thanks for checking with your friend. 

The more I think about it, the transmission issue will be the first order of attention when I return form Quartzsite (traveling in the service truck).

I also got a call from a person who reads this board, but chooses not to post.  He has a Series 50 in a bus that sounded like it had a problem like mine.  He said that a DDEC III boost sensor reacts quite differently from a DDEC IV.  He did some research and found several folks who had much better performance by switching from DDEC IV to DDEC III boost sensors (requires connector adaptation).  I can try that fairly easily since I have my DDEC III boost sensor.  One of the folks he mentioned was our own Blue Goose.  Jack, care to comment?

My mind is having a hard time absorbing this concept.  I did a search and did not find any direct hits.  However, I found several sites that talked about putting a resistor (actually a potentiometer) in the boost circuit to fool the ECM into thinking that there was more boost that actual and that would result in more fuel to the engine (more power).  Also found discussions about doing the same thing with the fuel temperature sensor.  I have no plans to do any of that, but it was amazing what I found.  Lots of folks out there doing "home brew" modifications to their Series 60s

Another step I may take is to switch back to the ECM that came with the replacement engine.  I have heard of folks switching ECMs with no problems, but I might have to go back to mating the engine and  ECM back together.  My thought was that I  could use my "old" ECM since I knew it talked well with the AutoShift.  My old ECM is actually a DDEC IV (used with my old DDEC III) and was new 53K ago.  The ECM for the replacement engine is also fairly new (replaced 163K ago).  Both have about the same HP settings (~~470). The replacement engine ECM has the J1939 activated, so it should talk with the AutoShift.

Driving to Quartzsite (presently in Phoenix today 1/19) has given me some time to step back and think about how I will approach the problem.  When I get back, I will not be up against a deadline, so I can pick away at it at a reasonable pace.

Jim

[DaveG]

Jim, if you are anything like me I think of great things behind the wheel but forget them when I get back to the shop, so here is a reminder to take notes of your thoughts/ideas.

[RTS/Daytona]

I believe this is posting that Jim is refering too

9/24/07  DDEC SLOW ACCELERATION WORKAROUND - OVERRIDEs SMOKE CONTROL SETTING

Hi - Good News for DDEC (I-II-II-IV) Owners with poor acceleration from a stop

I'm talking about Detroit Diesels with a painfully slow response when starting from a dead stop - seems their DDEC is set with  some kind of "smoke control" / "Throttle Delay" / "??" option - they do not smoke when you mash the throttle down

DDEC I -
Thanks to the work of Butch Williams - Luke at US Coach stocks an EPROM replacement for approx $100 that will cure most N.J. MCI DDEC I of their poor acceleration. DDEC I's have a replaceable EPROMS and are not programable
Note - The DDEC II-IV Fix (see Below) may very well work on DDEC I's  (We Just never tested the Fix on DDEC I's)

DDEC II, DDEC III, DDEC IV,
Bill Gerrie and Pete Papas have worked on this problem - Via long distance phone call Between Daytona and Toronto - Thank  goodness for "Unlimited USA/Canada phone plans) Bill used his PROLINK to verify and test the settings and ideas -

First a little history
The D/D DDEC TURBO BOOT SENSOR
old part#--> 16070629  new part#--> 23528418
is a 3 pin solid state IC device
pin A = Sensor Return
pin B = Signal Line
pin C = +5 volt supply line
pin B - operating range - approx .5v to 4.75 - voltages outside this range will cause a DDEC Fault

example
pin B @ 1.00 volts = approx 00 PSI Boost
pin B @ 2.25 volts = approx 10 PSI Boost
pin B @ 3.80 vollts = approx 20 PSI Boost

<>The PROLINK was used to verify the correct action of Bill's TBS without the modifications

<>Bill came up with a unique solution - A 100 ohm resistor between pin B (sense line) and C (+5 volts) - will pull up the voltage at the sense line (pin B) to what would be an approx 4-5 psi boost voltage level (as measured/verified with the PROLINK)

<>Just pull off the connector to the TBS and splice the resistor into the wires behind the connector

<>AS the actual boost pressure increases past 5 or 6 PSI the pull-up effect goes away - allowing normal TBS voltage levels

<>AT full boost the pull-up resistor has no effect

<>The net result is that the DDEC thinks that there is a little boost pressure available at IDLE and allows for more fuel to be delivered to the injectors upon acceleration

<>This does mean that if you mash the pedal - you will produce some black smoke- just use the throttle pedal wisely (especially in front of the smog control guys)

<>Idle still remained smoke free

***** UPDATE  130 OHMS seems to be the best solution **** 07/07/07
 
Pete RTS/Daytona

Your results may vary - use at your own risk !!

[blue_goose]

Jim,  From what I have seen here that isn't your problem.  Changing to the DD3  Boost control will only give you boost faster. 
Jack

[rv_safetyman]

Pete, I had forgotten about the information you re-posted.  Thanks for posting it again.

Jack, thanks for commenting.  I could not figure out why the sensor would make that much difference.  However, I may play with it later on.  I suppose that the present sensor could be bad, but I am still leaning on the  theory that the transmission ECM is the major factor. 

Jim

[RTS/Daytona]

Jack

I agree with you - the "slow acceleration DDEC work-around" is for engines that are slow accelerators - BUT EVENTUALLY ACHIEVE FULL POWER and not an answer to Jim's current problem

sorry - should have made that clearer in my post

Pete

[luvrbus]

Jim, I spoke with Cole this morning he thinks you have a wiring harness problem and wants to know if you used the one that came with the replacement engine or the one off your old engine. 

good luck

[rv_safetyman]

I posted this information on the Eagle website (http://www.eaglesinternational.net/forum/viewtopic.php?f=8&t=1246) yesterday.  Since many of you don't visit that site, I thought I should post it here.  

>>>>>paste from Eagle website>>>>>>>>

As a bit of background you can look at this thread: http://www.eaglesinternational.net/forum/viewtopic.php?f=8&t=1037.

At the bottom of this long post is a question about DDEC programming.

To bring you up to date: I had hoped to get the bus running for Quartzsite. However, on 1/13 I took the first drive and it did not go well. The transmission flashed several codes and the engine would not build boost and stuttered when the shifts were made. Obviously I was quite frustrated. Pat and I decided that I needed to step back and let my mind and body heal. We drove the service truck to Quartzsite and had as good of a time as the weather and "moteling" would permit.

When we got home, I removed the transmission harness, as I was pretty sure the codes that were flashed came about because of harness issues. I also had to extend the harness loom, so that I could mount the transmission computer in an area that has much better access. Here is a photo of the modified loom:

While modifying the harness, I looked at one connector that appeared to have a couple of problems. A wire seemed to have a cut and one of the pins for this connector was not secured properly in the connector. It was obvious that someone had done a poor job of repairing the connector as shown in this photo:

After getting everything hooked up, I checked both the transmission and engine for fault codes with my Pro-Link and got none. I then decided to take a test drive today (2/12/10). The transmission shifted flawlessly. However, the highest boost I could get was 15 PSI and the power was low. This boost was a lot better than the first test drive, but it is not correct.

I had pressure tested the charge air system and checked the turbo (seemed good and only has 53K miles).

I think one possible problem is that I could not get the engine temperature over 165-170 degrees. It was about 35* ambient and in spite of not having the fan on, it just would not go over 170*. The radiator was cool to the touch but I did have the Aqua Hot in the system and the hoses were warm.

So, the big question: does anyone know if the DDEC limits fuel (thus boost) until the engine is up to temperature?

Depending on the input I get, I may switch engine ECMs (I am using the one from my original engine).

Any testing will have to wait for a few days. The weather is not going to be all that great and I need to spend a few days getting my tax data organized  

>>>>>>>end paste>>>>

I want to thank all of you who have posted so much good information and called/emailed me with your thoughts and support.

Jim

[niles500]

Jim - Do you have an EGR on your mill?

[rv_safetyman]

niles500, when I installed the engine this time, I welded a bung in the exhaust pipe right next to the turbo (no safe place to install in the manifold).  However, I have not spent the money for the gauge yet.

I guess this begs the question why you ask?  I have a blanket on the manifold and turbo, so I can't  check the manifold for temp or temp differential from cylinder to cylinder.

The engine runs smooth and there is no visible exhaust that I can see in the mirror (exhaust is sent to the side of the bus rather than the rear).

Jim

[niles500]

Some DDEC IV's (I believe that is your new mill?) are EGR VNT equipped -

Condensation Protection
In very cold ambient (i.e. < 30F) conditions the engine will operate in a "condensation protection"
mode. EGR is disabled during this mode requiring a slower turbo speed. The engine will sound
"different". During this mode of operation the operator will notice a lower "boost" reading
compared to when EGR is active, however there is NO reduction of power.

More info here - HTH

http://diesel.btc.ctc.edu/Engines/Detroit%20Diesel/EGR%20s60techguide.pdf

[rv_safetyman]

Thank goodness the engine is non-EGR.  One less issue to deal with.

Jim