Mackpro

I don’t know exactly when the ceramic roller abs spring loaded push tubes were phased into actual production but they can be found in any ETECH engines out there as they can be used any ETECH out there, the ceramic rollers are quieter and if properly maintained they last longer than steel. But a spring loaded push tube must be used on the exhaust rollers as the .024” valve lash is to much slack and turns a solid push tube into a jack hammer and shatters the ceramic roller over time. The .016 lash on the intake seems to cause no trouble. That’s why valve adjustment and updating the rocker arm hold down bolts are important. You can sill get the ceramic or steel rollers

Neither . The ASET AC and AI Engines did not start till sometime in mid to late 2003 for the 2004 model year. A 2001 is also a confusing year. As that year you could have a regular Etech engine or a CCRS engine. And some parts between those two engines such as EUP’s, turbo , injectors camshaft won’t enter change with each other

There are 2 different cartridge style water pumps for the ASET engines , one for the AC engine and one for the AI engine. One has a 5.27 inch pulley and other has a 5.88 inch pulley, the wrong one can be easily installed and cause cooling issues.

The air line goes to a small solinoid mounted on a bracket on the far LH side of the fire wall under the hood. These solinoids are very prone to failure. So much so that we quit ordering trucks with air fan clutchs.

The install tool does it all . There is another tool that can be used to check alignment from the bottom but it’s not a true install tool

You have to pull the head, you drive them into the top of the block with a special tool . I would pull both heads and check all H rings for height and alignment with the tool . https://www.freedomracing.com/j-41683-a-h-ring-installation-tool-alt-st-271.html?___store=default&gclid=Cj0KCQjwyN-DBhCDARIsAFOELTkQYu8bovPFGcCPy2y3lwijWKKRUkv5vQDubzklDPSd8BvcFQuMN3kaAh8wEALw_wcB

I wondered about making the “Y” from metal gas pipe fittings , that way you could use 3 pieces of straight hose . A “Tee” and a smaller elbow and a reducer bushing and 3 pipe nipples and your done

On our CHU’s and CXU’s , we have be having to replace the short harness from the front chassis harness up the the coolant level sensor. . Either the harness ends went bad or wires pulled apart inside the insulation.

There are a couple of bulletins on this code. If a pre common rail MP8 engine , clear code and keep on trucking . If common rail engine then pressure test intake system , pay attention to charge air cooler/CAC for leaks .

https://static.nhtsa.gov/odi/tsbs/2014/SB-10082801-0699.pdf These are the 2 bulletins we always followed and fixed the issues 99% of the time .

https://static.nhtsa.gov/odi/tsbs/2016/SB-10083430-6903.pdf

Grade Gripper is sticking and keeping brakes engaged/ slow to release. Mack has released a couple of service bulletins on this . It was a common problem. Fix was a new solinoid valve and quick release valve

Factory/dealership HP upgrades for MP8 should be fairly cheap. If you have a Mack transmission and truck is out of warranty. The dealer cost to go to 505 is usually around $200 , the dealership will usually mark that up 30% or $100 and charge 1 hour labor to install it . If the truck is still under warranty the the cost of the download is the difference between the cost of the factory engine versus cost of a 505 HP engine at time of purchase. Usually $1200-1400 plus markup and labor to install . On some year models there is the 505 Plus download that has an extra 100 ft pounds of torque that you can get . You can’t get the 505 if you have a Fuller trans with a low torque rating or if you have a Allison transmission in a GU . They do have a 505 E download that’s for trucks with smaller Fuller trans where you get the 505HP but not the bigger torque. If a dealer is gonna charge $4-5000 for a factory upgrade, you need to find a new dealership.

The engine brake plungers are known to unscrew themselves and cause issues as well . Mack sent out a bulletin and tools to dealers to tighten the plungers . Every time we had the rocker arm shaft of a MP engine we would check the plungers and see if they were backing out https://static.nhtsa.gov/odi/tsbs/2017/SB-10090649-6903.pdf

It’s for your cab power. They do go bad . Mack later changed the set up to a large fuse instead of the breaker style you have .

Power comes through fuse 39 in the fuse box on the fire wall , then through the trailer ABS relay that’s in the same fuse box . Power comes out of that relay on wire # 39-B-5.0 that goes up to the trailer buss bar, then it’s connected to the blue wire that feeds the trailer

On common rail engines, there is a electric fuel pressure solinoid on the end of the fuel rail under the valve cover . It was a common problem and we had all ours replaced with a new updated part number solinoid and also harness. It caused low fuel pressure problems and low power . There is a bulletin on this from Mack and is on both MP7 and MP8 engines

Pull the fuel supply pump . Check for play in the shaft, should be none. You can spray soapy water on shaft while shooting air into the inlet and outlet abs check for bubbles, other wise here’s what we used to do . Put fuel dye in the primary (first filter) and run the engine for about 45 seconds to a minute. Shut off engine and cap off fuel return line on the side of the block above the air compressor. Hook a air pressure regulator to the inlet of the primary fuel filter inlet and pressurize to 40-50 psi . Drop the oil pan and use a black light and look for leaks. The EUP pumps will always seep fuel to an extent , but not enough between oil changes to cause issues. If you find a EUP leaking, they do make a 3piece lower o-ring for damaged bores . Also there there is a fuel galley plug behind the timing cover that can leak but it rare .

I’m my notes, on a 2010 emissions truck during a regen the boost is 1.8 to 2 psi, however it doesn’t say with or without DRV valve , only the first year or two on the 2010 emissions year trucks used the DRV , they later made a kit to delete it along with a software download

Look at the bulletin in the next to the last post in this thread

https://static.nhtsa.gov/odi/tsbs/2013/SB-10054292-5095.pdf this Bulletin might still apply even though yours is not a MRU/leu

Is the oil level over full? Fuel in the oil is a likely problem.

About 10-15 years ago I spent a lot of time trying to figure this same thing out . This was the days of many trips to Radio Shack for resistors . The temperature one was somewhat easy , I had it set to around 250 degrees. The flow meter side was a totally different thing . In the engine ecm it calculates and sets a target flow that the flow meter should be reading , if the target flow was 12 pounds and the actual flow was 2 pounds you got a fault code for low EGR flow. I believe the target and actual flow has to be within 10 pounds of each other of you got the fault code . The target flow as always changing due to engine load and rpm. I thought about putting the flow meter sensor in the aftercooler piping and seeing if it would read close enough. I lost interest and sent all my stuff on this so called EGR delete to a guy on here from up north, he was way smarter than me but I believe I gave up too after a while.

The 4094 and 5246 codes seem to always come together. We had 3 of our truck go down in one day due to these same codes. Cold weather seems to make them happen more than the summer. Poor DEF quality, bad NOX sensors, DEF doser not spraying enough or in the worst case a bad SCR box due to coolant or oil contamination from a past EGR cooler or turbo failure. On your year model the regen temps should be around 625 T1 and 880 on the T2 . As long as the T3 is higher than T2 your probably ok. Main thing Is T2 being 880 or higher. . ( Newer common rail engines have much higher regen temps ). You will usually never see a NOX reading during a regen till the last couple of minutes. Engine fuel pressure should be around 65 psi during a regen . Years ago we used to start a regen with tech tool , unplug the interface adapter (vocom) from the truck and back out of the regen screen plug back up to the truck and go into the screen where you could pick any sensor to view, I think it was Sensor Monitoring something like that , we could pick the NOX inlet and outlet and watch it while the truck continued to regen . I have all that stuff written down somewhere in my tool box . I’ll see if I can find it tomorrow

Some of our common rail engines are now over 200,000 miles and still trouble free ( all MP8) other than the fuel rail valve and pressure sensor, there are CBR bulletins on replacing them with upgrade parts and also replacing both under valve cover injector harnesses. However we still have issues with random things. Our biggest issues right now are the Mack inter wheel locks blowing apart . I wish we would order them with the inter-axle air power divider only. Also our Mack T-310 trans seem to really like to go back the dealership for hi/low synchro replacement every 18-24 months. Our last 3 new trucks have the M-drive transmissions and drivers fight over who gets to drive them . I love them , less clutch’s I have to adjust. The LCM ( light control module) that was brought over from Volvo has been an adventure. A simple lighting issue is now a major pain the the butt. ABS wiring in the frame rails shorting out the rear wheel speed sensors now cause the speedometer to quit working and derate due to speedo tampering parameter on . Had three trucks in a week have this issue. Also we have found loose main ground wire on the inside of the cab at the pass through on the firewall above the throttle pedal to be the cause of many intermittent random fault codes .