Mackpro

Last September I did 9 sets of injectors/cups in a little more than 2 weeks so that’s burned into my brain. Plus all the years at the dealership where i amassed two 5 gallon buckets of just copper cups when we were doing the change over to stainless cups., never bothered to save the stainless ones .

Mack updated the torque specs for the rocker arm shaft a while back. Some of the older books might have have the old data in them . This is only for the rocker arm shaft on the MP8. Tighten all hold down bolts to 44 ft pounds. Then one at a time, loosen and retighten to 30 foot pounds except the large single bolt in the rear , it stays at 44 for now. Then tighten all 120 degrees ( including big single bolt ) . This is 2 flats on the bolt head .

https://static.nhtsa.gov/odi/tsbs/2013/SB-10082932-6903.pdf Scroll down to the pics of the injector sealing areas. If any of the injectors looked “ unusable “ then the cup and injector needs to be replaced. This is a old bulletin but useful information. Mack now says don’t do the thread tap and pull on the stainless cups as the thread shavings were wiping out turbos left and right. Mack now has a expanding puller that grabs the sides/walls of the cup and pulls it out super fast. On copper cups you still have to use the thread and pull tool method.

Did you have install tool to form the end of the cup to the head ?

Mack issued many bulletins on the fuel filter changes. I can only screenshot them due to the new format. So I can’t really get all of it in the picture.

The Mack /Volvo filters for the common rail engines

I have also had to loosen the rear filter and remove fuel tank cap abs stick a blow gun in the tank and stuck rags around blowgun and shoot air into the tank till fuel started coming out at filter stand then tighten filter. Make sure your using the correct filter also. The fuel filters for the common rail is different and all the early MP engines. Mack only approves certain aftermarket fuel filters to work

Here’s a pic with the flapper removed and the hole clogged with black crud. Top left of picture. This is only on the common rail engines starting around 2017-2018

On the Mack common rail engines , they have done away with the fuel pressure relief valve . So any leak or issue makes them hard to start. Does it have the 2 spin on fuel filters or one spin on and the Davco filter? If 2 spin on filters, remove the rear filter and look at the bottom of the filter stand. You will see a orange rubber flapper with a metal spring wire holding it closed. See if any debris or trash is holding it open. A Phillips screwdriver can remove the flapper for a better look . Clean it out . This is where the fuel comes in from the tanks and seems to get trash stuck in there .

Is the starter turning the engine over? Go into trip data in your dash display and look at engine hours. If you only see dashes for your engine hours then the Engine ECM is not powering up or gone bad. Also the engine ECM controls the ground on the small solenoid that’s bolted to the starter.

https://static.nhtsa.gov/odi/rcl/2014/RCRIT-14V078-3643.pdf

Fuse panel down by the clutch pedal is known to get water in them . Major recall on them years ago

I’ll see if I can find the digital copy

For some reason # 5 or # 6 was always the location this happened at

Roller looks perfect

Screw in new bolt down in the hole to about the depth it normally rest. See if you can wiggle the bolt in the threads.

I believe I have a MH heating and air conditioning service manual at work. I’ll see if I can locate it and see if it has any thing you might could use

The cam sensor and crank sensor work together. When one goes out it will still run but like you said, hard starting. I believe it’s like 8 seconds of crank time before it starts .

Have you had any work done on the back of the engine like bull gear, camshaft or upper timing gear cover replacement? If not just use your original shim or shims. I don’t think I’ve ever had to re-shim one even after the above mentioned repairs. Hopefully the new sensor fixes it. I’ve only see maybe 2 sensors go bad. Most we’re erratic signal codes and it was the engine harness bad. I believe these sensors produced AC voltage and the faster the engine spins the higher the voltage. The harness usually test good but at high RPM’s the faulty harness can’t handle the higher AC voltage and sets the code.

Yes , that’s for the MP10/D16

I got to test drive the truck I been working on for a couple of days before I went home today. 2012 CXU 445 Econodyne. 10 speed Fuller. New turbo , new EGR differential sensor upgrade kit installed, new EGR temp sensor, no boost leaks, clean DPF with only 1% soot . Pulling a empty but heavy feed trailer . On the interstate coming up the biggest long hill we have around here. I accelerate up the hill and took this pic at 1650 rpms at 72 mph and max boost I got was 33 psi , I hit 75 at the top of the hill. I’m wondering if emission years and HP differences make a big difference in actual max Boost pressure. My buddy who had the 2016 505 Plus program can’t remember his boost numbers in a hard pull. I road with him once to the grainery and we we’re pulling same hill loaded easier that I pulled it with my empty trailer. Gross weight was 101,000 when we weighed at the grain bins. Best pulling Mack I ever road in.

I guess I should have asked but what year model is the truck and is it deleted now or was that in the past ? And what’s the Hp on the sticker on the valve cover?

To gain access to the sensor you can turn the steering wheel all the way to the left , remove the black plastic fender/splash shield from the cab and step bracket and get down between the tire and frame and get to the sensor. Some trucks this works on and some not . Plus it helps if you got skinny long arms. To check the harness at the back of the engine you gotta go in from the inside and pull the doghouse cover off as Joey said. Also , is this a MP7? If so there were issues of the harness rubbing on the air compressor head and causing injector codes and cam sensor and crank sensor codes. All those wires run together towards the back as the injector wires go in the back of the head. On a MP8 the injector wires go in the front of the head so there’s less wiring towards the back of the engine.

There is a depth measuring tool to tell how many if any shims are needed to install a new sensor. Really the only time you need it is if you have had the upper timing gear cover off or replaced the cover. Honestly, it’s usually the harness or harness end. I’ve only replaced 1 or two of the sensors ever. Pull the sensor and check for damaged end. Using a ohm meter you should have 775-945 across the pins on sensor.