Mackpro

Awhile back we were able to get the inlet NOX sensors but not the outlet ones . Now that has reversed and the inlet ones are impossible to get. The dealership we get parts from heard yesterday from corporate that things are going to get worse. We did buy 4 of the Dinex outlet nox sensors about 4-5 months ago due to trucks down . 3 of the 4 failed but it got us out of a jam till the factory ones came in. The failure rate and issues caused by the aftermarket and counterfeit nox sensors was so great that Mack released a bulletin on how to spot counterfeit and aftermarket nox sensors. . As far as the boost leak , don’t take the rear EGR elbow pipe off unless you have a way to pressurize the intake system. You can actually make things worse. The elbow has a floating collar and is a extreme pain to get sealed. We have a tool that goes on the aftercooler and pressurizes it and the intake manifold which in turn pressurizes the EGR system and you can locate your leak. If it is the elbow connection , use new gaskets and clamps . You will find you will need to readjust the clamp and collar a few times between pressure testing to get it air tight. There has been times I’d wished for a super greasy clutch job than to reseal that elbow.

What’s the model and last 6 of VIN ? Such as CHN613 ,CXN613 or CV713.

The bad thing about the common rail valve adjustment is the fuel rail is in the way and I had to buy new straight feeler guages to go under the fuel rail to reach some of the valves. The clearance’s on the MP8 common rail are the same as the old MP8’s though. I’ve been told that on the common rails that MP7 and MP8 uses the same pumper and non-pumper injectors. The injector cup is still the same part number but they redesigned the injector hold down yoke and went back to the shorter hold down bolt that the very early MP engines used. The one I had apart today already had the EPRV electronic pressure relief valve delete done at the factory. All of our older common rails had to have the EPRV delete done at the dealership usually around the 100,000- 200,000 mile mark .

I use a Bluetooth snake camera looking at my camshaft marks . I can zoom in on my phone while turning the engine over to see the marks. Works great.

This truck runs almost 24 hours a day short haul/ farm related. Already 137,00 miles , routine maintenance. It’s listed as a 22 but we got it a little more than a year ago.

Camshaft marking will be 5/PE6 , 3/PE2, 6/PE4, 2/E1, 4/E5 and 1/E3. On 5/PE6 you do intake valve on #5 then #6pump(injector ) and #6 exhaust . On 2/E1 you do #2 intake and exhaust on #1. If your lucky the marks are stamped on the camshaft. The 2022 I did this morning, the marks were laser etched and almost impossible to read

It’s somewhat different than regular MP’s , I’ll post some info shortly

SB-261-008 is the service bulletin on the air compressor coolant line re-route . This is the only link I could find online. https://www.yumpu.com/en/document/read/31273801/service-bulletin

https://www.bigmacktrucks.com/topic/59842-casting-sand/

Make sure you replace the small line that goes from the coolant tank to radiator/upper radiator hose elbow. This line can collapse and cause issues like air pockets and only being able to fill with 2-3 gallons of coolant rather than the 10+ gallons required. The 2000-2001 year model ETECHs had issues with engine blocks not washed out correctly and the sand from where the engine blocks were cast would settle at the back right corner of the engine block and block coolant to the air compressor. Almost always you would find the paint cooked off the head of the air compressor due to it overheating. Twice in one day we had 2 trucks towed in where this happened and the air compressor head gasket blew and pushed coolant back through the fresh air intake pipe which goes around the back of engine and into the back of the intake manifold. Coolant got forced into the #6 cylinder and hydro-locked the engine and bent the #6 connecting rod so bad we had to cut if in half with a torch. Mack came out with a new coolant fitting for the back of the block then later instructed us to run a new air compressor coolant line around the back of the engine and into the water manifold to totally get away from the core sand issues .

https://www.bergeystruckcenters.com/efs/wp/domains/www.bergeystruckcenters.com/wp-content/uploads/2021/09/REMACK-Product-Technical-Brochure_compressed.pdf Here is the Mack reman catalog, it’s helpful in part numbers

The 5.27” pulley is for the AC engine in the CX/CXN and the 5.88” pulley is for the AI engine in the CV, CT , MR and LE and possibly some of the last RD’s and CL’s . The smaller pulley pumps more water to cool the EGR cooler .

the AC ASET engine and AI ASET water pumps are the same pump except for the pulley size. If wrong one is installed you will have cooling issues

He have been getting bad AC compressors right out of the box for our Anthems and CXU’s . We started Ohms testing the clutch before we put one on now. And these are Mack ones for the dealership. The HVAC control panel and the door panel switches also seem to have a high failure rate . The newest door control panel part numbers seem to do better.

Only bulletins I’ve found is for older trucks bumping the software up to go from the 2G to the 3G networks. There are always updates for the Telematics/TGW popping up when we plug in Tech Tool. We just got in our first 2022 ( built last month) and the only software updates needed were for the TGW .

Check the banjo fitting in fuel line that goes from the Engine ECM cooler plate to the the filter stand . Trash gets pulled through the fuel lines , through the Engine ECM cooler plate then lodges in the banjo fitting at the fuel filter stand. Be sure to look inside the fuel line itself. Being a 2015 it should have quick disconnect fittings on the fuel lines on the Engine ECM. Earlier MP’s had banjo fittings on the cooler plate that would also clog.

I found my Mack tube up /Spec book for the 1996 year models. A EM7-300 mechanical should be makeing 20-28 psi in a hard pull . Check the fresh air intake piping for the air compressor. The air compressor get it fresh air from the intake manifold. Any leak on that any you will loose boost. The original intake manifold gaskets were later updated to steel core gaskets due the paper gaskets blowing out

Did you have this issue before the Delete? Did this truck have DEF fluid/SCR system on it? The combustion valve on the intake manifold could be stuck open or leaking abs sending boost pressure into the bottom of the DPf housing. Fuel pressure needs to be around 55 idle and 65 at 1200 rpm. Boost pressure should be hitting 31-32 psi under a load . Turbo wheel speed should be hitting 109,000 RPM,. Any boost pressure leaks can kill a MP7. Boost pressure sensors are different between SCR engines and non SCR engines. Wrong one can cause low power. Any major tire size changes? Going from 22.5 LoPro to 24.5 full size with out changing the revs per miles can really mess one up.

Good reminder FJH, ask for new bolts because with the new thicker manifold the old bolts will be to short,

The SB215057 only applies if your using an original old style intake manifold

https://www.scribd.com/document/514541769/sb214061

Mack service bulletin SB214061 shows the new design intake manifold for MP8 and MP7’s that use the longer bolts but no spacer. If your intake manifold is not broken and your just replacing the broken bolts the service bulletin SB214057 shows using the longer bolts with a spacer , I will try to attach links to the bulletins

There is a service bulletin on the intake manifold bolts . They came out with some new longer bolts with spacers on the ends . The broken bolts and intake manifolds we’re common more on the MP7 than the MP8. But seen plenty of both . The broken bolts usually come out easily sometimes with just using a pick to spin them out. If you do have to drill them they are very soft and drill easy.

Yep. I know the ASET AC engine takes a special boost pressure sensor . I believe the ETECH, CCRS and the ASET AI all take the same part number . They all look the exact same and it’s easy to put the wrong one in . And yes it won’t run right it if you do put the wrong part number one in.