Mackpro

Oil temp sensor is in the oil pan on all the MP series engines . And when I say in the oil pan , I mean you have to remove the oil pan to replace it . The oil level sensor is also part of the oil temp sensor.

There was a recall on the flasher on about 24,000 CHU, GU and CXU models . You really need to get a flasher from a Mack dealer . The prongs are extra long on the Mack flasher, this is needed as the wire connection are deep in the fuse panel. Standard electronic flasher prongs barely reach the wire connections in the fuse/relay panel . Also check for the wires pushed out the bottom of the panel . Lastly, if all looks good , replace the turn signal switch, we still go through turn signal switch’s in our fleet.

The AC 310/330 Maxi-cruise was a common engine in the single axles Mack’s . It puts out 1360 ft pounds of torque which is that a AC 350 has . It shares the same injectors as the 330/350 and 355/380 engine, it also shares the same turbo as the 330/350. It could possibly be upgraded to a 330/350 with no hard parts changed if you could find a dealer willing to do it .

I think it’s a good ideal to replace the thermostat and coolant pump. These items are easy to replace and not super expensive and will fail not to much farther down the road if they haven’t already . As others have said the fan clutch/ air flow through the radiator is also a high on the list on possible cause of overheating. There is a good chance you have the much hated Borg Warner Cool Logic fan clutch. It’s easy to tell if you got the Cool logic fan because it’s super huge with heat sink fins all over it . They were a total failure and are no longer made . They actually leak oil and start slipping and gradually fail to the point that the issue only shows up on hot days . As others have said I’d first take the grill out , raise the hood and take the condensed loose and lay to the side . Pull the charge air cooler / after cooler and wash out the radiator. We replaced a couple of fan clutchs when it really just needed a radiator fin cleaning. Theses were farm trucks though. https://www.fanclutch.com/PicsDocs/BorgWarner_Cool_Logic_Diagnostic_Guide.pdf.

This happened to our one Anthem that we got . It’s clean exhaust at that point so it was not a huge deal at the time . As long as the hot exhaust was not blowing on anything important. The drivers never noticed it and we only found it during service/inspection. Both of my buddies new GR ‘s ( the new GU) have had the same issue. Our last new CXU’s with the common rail engines and one box SCR/DPF have not seemed to have this problem.

Always make sure your heat shields are in place to protect the EUPs . On some chassis’s the exhaust pipe is really close to #5 and #6 EUP. Even with the heat shields in place the those back two EUP’s take beating from the heat off the pipe. We see the back two fail more than the front 4 . Remember that there are 3 different part numbers for EUP’s . All three look exactly the same . Also the middle o-ring is no longer used and on some the later castings the O-ring groove was totally elimated .

We have one Athem in our 25 Mack fleet and so far so good , but we had a few minor issues ( which I found out is very common) and one design change made a maintenance item a lot harder to do. First off the all Mack poewrtrain has been great . Only a couple of software updates have cleared up any codes we had. The M-310 trans and Mack rears have been good as well. We have heard of oil consumption issues with the common rail engines but our 4 have been normal. Here’s the issues we see. First , the door control panel that works the mirrors, windows and locks have gone out twice . This is super common, the control panel is actually a ECM and can flash out a error code if needed . Volvo butted in and forced their light control module in on Mack . So all the lights go through this ecm , there are 6-7 fuses that power this contraption . We replaced the fuses with breakers due to on going fuse blowing due to the many random trailers it pulls. Lastly the cabin air filter which was super easy to check/replace/clean is now way harder to access due the rest-design. It’s in the same place but harder to get to . All in all it works every day and I can’t complain any more than that .

On the VMAC 1 engines , they had a 10 degree econovavce which was later bumped to 20 degrees and was carried over to the VMAC 2 engines. The fuel pump was static timed to 5-8 degrees (depending on emissions year) then the econovance would advance or retard the timing as needed. On the ETECH engines, I never found any data on timing

Get the rocker arm bolts replace with th newest part number , get the valves adjusted and software updated as well . And when you drive it just hold it to the floor , you won’t hurt it .

The mileage is calculated and stored in the VECU ( vechicle ecm) . The engine hours are calculated and stored in the EECU ( engine ecm) . Both ECM’s send the data to the dash cluster. Has the VECU been replaced or reprogrammed latley? Does the the speedometer work correctly and is the transmission a Allison or a Fuller ultra shift? On a manual trans the speedometer sensor transmits directly to the VECU. On a Allison the speedometer sensor goes through the Allison ecm I believe.

Only the truck models with the MP engines need programming when replacing the dash cluster. On your model truck , the mileage is stored in the VECU and engine hours are stored in the engine ECM’. You can replace the cluster your self , it’s not hard.

Yes , that’s on the cheap side for a MP engine. When I was working at the dealership, the actual download cost from corporate to the dealership was anywhere from $200 to $1300. Of course the dealership marks that up then add in a hour of shop labor for install.

I sent you a message about a wiring diagram. Hopefully it will show what you need .

Mack came out with a conversion kit to replace the two VMAC 1 ECM’s with a single VMAC 2 ECM . The wiring harness on the engine remained the same as original. Chances are the one of the original VMAC 1 ECM’s failed and the conversion kits was installed.

Here’s the easiest way to tell a VMAC 1 from a 2 on a CH style truck . A VMAC 1 has the engine harness plug iinto the firewall right above the windshield washer fluid jug on the passenger side of the firewall. On a VMAC 2 truck , there is a block off plate above the windshield washer fluid jug . Also , the Econ-Vance is a lot longer on a VMAC 2 and the injection pump almost touches the air compressor, and of course the VMAC 3 is an ETECH style engine with the heat shielding over the individual injector pumps

We alway tried to achieve 33 psi of boost under a pull with the 460 AC engines. I have seen a few go higher but we were happy at 33 psi. Worn out boost pressure relief valve or cracked after cooler or malfunctioning turbo actuator were some of the reasons for low boost

There is a factory valve spring compressor that works awesome , it’s downfall is that the injector has to be removed

We would pull the intake manifold off and drop the intake valve down. Then blow air into the injector hole and blow the little pieces out the intake . Saved us form pulling the head off .

Only saw a few of the stainless cup tips break off. Saw lots of the copper cup tip break off when using the newer style puller. Lucky we held onto the old style tool that taps threads into the cup tip and then uses a pulller that threads into the cup .

Truck created on 2-10-2000, transferred to sales on 2-21-00. That’s all I could get my dealership guy to find.

We saw burned valves , cracked liners and cracked head. To much fuel and clean air and they burn pretty hot.

The max HP rating for a export MP8 with no EGR is 440. I’ve seen 3 major engine failures on low mileage deleted MP8s . One I know was a 505 , the other 2 I’m unsure on HP. I would feel better if the EGR was not deleted but the DPF/SCR was

Volvo has had the injector cup problem in the D12 and their other engines before the D11,13,16 and MP7,8 and 10 came out. Back in 2008 I went to a Mack engine class on the then new MP engines. In the class there were also techs from some Volvo dealerships. The instructor kept going over injector cup installations. After 4 + hours on injector cups , I asked what’s the big deal with the injector cups, the Volvo techs laughed and said I needed to pay attention because I would be using my new knowledge and they were not kidding.

I believe there are a few service bulletins on the LR climate systems. I’ll message you for details

It’s the piston cooling oil pressure sensor. Same part number as the oil pressure sensor on the other side of the engine.