6/20/10
I own a few mc9 buses, all in-which are mechanical 6v-92. my problem is: I brought an wrecked 1994 mc-12, Detriot Diesel, vin #1m8rcm7a4rp046019; original engine#6ff015645, model #80677b27 ( ecm ddec III – I am told ). I searched high and low for an engine and was told for this model, I would have to replace it with an transit 6v-92 RH in which comes with a ddec II? I purchased one from a company in So. Cal, the new engine block ( 6vf157885 – ddec II), took some parts from old engine to reconfigure with the new engine ( engine would not start – I had to put back on old cam; in which had the original sensors ). After finally, getting engine to start, put engine in to discover a couple of injectors bad and need head job ( pulled engine again ), after accomplishing an in-frame to over heated damaged engine; and replacing ddec II with ddec III ( from valley power ), because, the existing bus harness’s would not line up? Now, the bus starts and runs, a new problem occurs the bus will not go faster than 45 miles an hour?

I put the bus back in the shop for the third time, shop thought it might be fuel pump, did not work, shop changed the cam – due to worn out notches ( only four – now 10 or so notches ); this still did not get the rpm over 1,675.0 according to the shop ( valley power states that the minimum in any detriot engine should b 1,800.0 ), next the sensor was replaced, and the problem still exist’s the bus only goes 45 miles an hour? I double checked the engine information by bringing the ecm ddec III back to valley power, the printout reads that the ecm s/n: 11501295; peak torque lb-ft: 0880; rated speed rpm: 2110; horse power: 300; software level: 0154, all is the correct parameters.

Something, somehow, is set wrong? Valley power originally told me to bring in the old computer to so they can copy it and flash the new computer; now they said they set it up with the old engine serial numbers, have they mixed things up in the old engine ecm ddec II box and forgot to do this with the new ecm ddec III box? Or does this repair shop not know how to read the prolink meter? Now they have tried to ground the bus with five volts ( with a load on it or off it )? They have tried an pressure test, in which suppose to be 0 – 100 for this engine accelerator or between 400 – 850? They are now tring to check the turbo? We are really at an stand still? And are debating to try another ddec III motor with the ddec already attached? Or trying to make the existing motor an manual engine and I was told the cam sensor would become a problem again if we went this route?
All ears open and opinions respected,
Newownerlearner.

 

Them be General Motors Engines. Most 92's are 71's borred out without a larger bottom end. Did not last to long in marine applications. You should call
a Detroit Diesel affiliate.

Here is were to start;

Florida Detroit Diesel-Allison
6850 Presidents Dr
Orlando, FL 32809

(407) 888-1700