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On 8/1/2023 at 6:41 PM, JoeH said:

Let's start with basic. 2 sensors trigger the shutdown alarm. Oil pressure and coolant level. Replace them both.  The coolant sensor has a problem "wicking" coolant along through the sensor to the EECU causing pins to rot out on the EECU. Maybe your coolant sensor is failing. I think there might be 2 oil pressure sensors, one for the EECU and one for the gauge. I think. Joey Mack can correct me, and describe their locations. 

I totally agree with this check the ECU plug .Also the VECU plug under the dash if it gets wet it can cause issues if the wind shield has been leaking!

If its wired correctly it should have relays in the fuse panel just swap out a like relay in the panel with something else hi beam or some thing see if it changes the situation!

Fuel pressure is too low under load ! Check for a broken spring in the fuel return T or a restriction on the fuel lines or filters!Needs a minimum 20 to get full power!

Replace the relays!

31 minutes ago, Anonymous said:

Hello everyone.  Have 1990 ch613 with a 9 speed and an E7 400 all mechanical motor that is very sluggish. This is my fist Mack bought to pull equipment and haul grain. Truck was bought as a project with a blown engine. My dad and overhauled the motor and had the pump and injectors sent off and checked. Pump shop put new delivery valves in and set it to 10% over factory specs. We set the timing to 21 degrees. Pulled my first load with it last night. It was a light load and then truck is just slow to rev under load and has a shutter/serge. Checked fuel pressure at pump and have 20 psi at idle but have no clue if that’s in spec or not. Anyone know what the fuel pressure spec is? Only builds 20psi of boost. So I will be checking for boost leaks.  Did find the air line to the afc was cracked and replaced it thinking I found the problem but made little to no difference in power. For reference I feel like my old ford with an L10 has the same amount of power as this truck. Any help is appreciated. 

Temove the line to the afc and suck on it if you can suck or blow thru it the diaphragm may have a hole in it! Also check your linkage and stop for going full on full off!

If the the shut down is not accompanied by a malfunction light  nothing will be logged! just something to try, reflash the ECU! also just a thought ,I Wonder if something was set in the over speed section of the EECU that you changed ! either way a reflash my correct this!

1 hour ago, tjc transport said:

this is a rough service T880 Bob. 

the 2016 had 120k miles when sold and the 19 had 75k miles. no issues on either one. this truck is not what we ordered, but i had to take it because the old truck was already sold. 
my friend has 12 with over 300k miles on them no issues. and his drivers run them hard and put them away wet. 

my trucks are taken care of. 

i really think it was a fluke in the trans. 

 

Maybe a Friday/ payday  Trans!  Shit happens unfortunately! The important thing is that the warranty will cover it ! The unfortunate thing is that warranty doesn't pay for down time!

Interested to see how this plays out! We one had a truck sit at our shop waiting for drive shafts for a month while someone had to make a decision the the wrong drive shafts got installed at the factory on a tri drive! Took out the rear bearing on the middle diff!

3 hours ago, Joey Mack said:

you will never find the great info that MackPro provides for free anywhere but here.. 

👍💰

As mentioned change it out to the air fan they are rubish! Do it once and be done with it! Chances are the new one will be kick right out of the box! Note you will have to have the program changed to suit the air fan!

Tire need to be roughly 3/4 to 1 of an inch below the top frame rail loaded or not! There is a proper gauge for this how ever this is a get by! Experiment with it! There is an 18 mm head bolt that holds the ride valve to the frame  loosen and tweak the bracket. And tighten bolt the bags and refill and check the height it’s easier if you on a flat slab and measure from the slab to the frame at the back it’s all doable from the outside!there is usually a hole you can bar through to change the mount bracket height!

19 minutes ago, Stacyb said:

Mack 2013 ch613 vibration starts at 50 gets better at 70  driveline balanced new u joints does it bad when loaded trailer at 50 to 60 new tires didn’t change this balance didn’t help feels like it’s in floor then sometimes like seat little in steering at times new back motor mounts  any help would be greatly appreciated 

Air suspension? Ride height ?

19 hours ago, Supermutt said:

I dropped them off to be tested a a Bosch pump  shop. The guy there said the green paint marks were a QC mark from the bosh factory. They are most likely the original injectors.  Pretty sure they are going to be nfg. 3 out of the 6 definitely had bad o-rigs as they were soaked with fuel and leaking out the head. 

You should be changing your oil then!!! 

1 hour ago, Dtech said:

Yes I have checked for boost leaks, The black smoke is only when I was manually moving the Rack inside the fuel pump. Items I have checked so far Turbo, Intake, air filter, air compressor supply line, Air charge cooler, Fuel psi, exhaust restrictions, valve lash, Cam Timing, Injection timing, Tps, intake air temp sensor water temp sensor. The scanner shows it going to 100% load. I can only watch the following parameters oil psi, water temp, intake temp, tps, load, rpm, road speed, and voltage. Can anyone shine some light on the torque limit circuit for mac I, why would wire 36 be labeled positive and wire 46 be a ground? I also don't understand why the wires have voltage on them. 

Bro!
So post the model and year of truck and last six of the vin there are guys on here that may be able to help either the vecu wiring set up . I no longer have access to this stuff ! There are a few here that may! I would think there would be voltage down one wire to that switch! And back to ground at the vecu! Does the power show up at the wire at the switch?at the transmission? If so a full 12v or .7

That is the switch the wire I’m not sure! Have you checked for boost leaks black smoke is a good sign! You got fuel! lack of air may be your issue! Air filter new? Check the turbo ! Check thectube at the compressor inlet and at the manifold left side for holes also by pass your air drier temporarily for something to try! They can dump boost as well!

So I need to ask what trans do you have and are there any codes coming up other the the inlet air ? If you have a 18 speed Tran s un plug the low range switch at the rear shift cylinder see if this changes things! If the wiring to this switch has rubbed together anywhere between the switch and the vecu it will de rate the power by 50 percent! This will not throw a code the computer will think this is normal!follow that trouble chart you have posted there if you can locate the two wires to the switch cut or remove them from the vecu plug this way the vecu will never see a closed switch!

14 hours ago, 70mackMB said:

Will!  Thank you for posting what the problem was. Too many never let us know "The rest of the story".     .....Hippy 

Agree totally with this statement ! spring brake is the most common failure with this symptom, there are a few other issues that can happen How ever yours fell in to the most common category !    Thanx for posting the fix! 

All good bro ! Took the leaky boom cyl out had it repaired and repaired  to the tune of 1600 other than that it’s working out well! Haven’t had much seat time yet been busy with other shit! Thanks for asking! I think after using the 4x4 I can hear a bad u joint in one or both of the for lack of a better term cvc joints bit of clattering on turns!   May have to address these at some point apparently there are 2 u joints per side! not to much info on line but haven't searched hard on this yet been too busy with  other stuff!  

2 hours ago, R.E.D said:

My 10 speed t310m had a similar issue, shift fork was very worn also in conjunction with worn synchro gear ...I took the rear cover off and welded the shift fork up and grinded it down to size..this quick fix got me through the busy summer..then rebuilt the whole transmission..like FJH mentioned,the rear part can be removed but will need a specialty bracket to hold the 3 shafts in place...if truck is new to you ,I would remove transmission completely and have it gone through....main boxes are kinda bulletproof, synchros are the Achilles heels.

 

Just my .02 cents

RED

Yup to avoid buying tools pull it stand it up on a wheel rim of the appropriate size or two 6x6 wooden blocks and pop the back cover ! Recommend checking the rear bearings on the main case while you’re there how ever not nessary just a precaution!

2 hours ago, mrsmackpaul said:

Just drop the box out, stand it on its bell housing and lift it apart, PAI stock all the parts as far as I know

They are pretty simple to work on

Use the proper gaskets and silicon, sicka flex or form a gasket and you'll be right

Must of been a pretty hard change that broke the gear or dog, these boxes are regarded as pretty indestructible 

 

Amyway as to the 18 speed, it will fit but Im thinking a fair few changes are needed

 

Paul 

Agree with Paul ! If you have the access to an 18 speed fuller( out of a Mack) then that would be an alternative ! That said you will loose all your back up speeds fuller has 2 your 12 speed has 5 ! The problem may involve a broken shift fork or shift rail ! the model of your unit makes for a difficult remove narrow frame ! You could pull the floor plate remove the center shift lid and look at the rails and forks how ever it sounds like the trans has to come out! Can you post a picture of the piece you have found on the drain plug! the only dog clutches in this are on the splitter and you still have hi /low Correct?

3 hours ago, Digger Dan said:

Only low range gears and I believe in high and low on the splitter. (1-10 if I am counting correctly)

Plan A

just sayin! It’s a pricey project however! Is what it is! 

Nice my favourite! Model bar none for a dump truck !stand up oil change!😂It’s best to pull the transmission hatch if the box controls haven’t been mounted over it you might get lucky most box guys don’t consider that someone may have to pull the transmission some day! The trans can stay in the truck to do the back section but likely have to go to the dealer to have it done! Still check the yoke bolt and fork bolt also answer joes question there that is important too for proper diagnostics!

Cl713 likly has a Cummins in it! Check the rear output yoke for tightness! These were quite an issue behind the Cummins ! If it’s tight remove the top rear shift lid and check the shift fork bolt ! If it’s tight then the back section of the trans may have to com off and neew synchro plates installed!

Yup good thought Joe ! That said had this happen many times ! Shit got in the injector on installing of the line just my observation! AC engine particularly bad for this because of all the crap in the way !Replace the injector! Good to go! Cylinder not getting fuel! 
just sayin!