c-mac

I have a mp8 rocker shaft lifting tool. Gonna put it on eBay this evening. It’s the real deal!

I have an extra rocker shaft lifting tool if someone's interested I'll make them a deal. pm me

there is a fuse in the drivers side fuse block by your left foot. I dont remember which one but if it is making noise the fuse is probably ok. I cant If the acuator makes noise continuously Move the harness around to the actuator and see if it changes anything. the pins in the round connector can look fine but still be bad.

If it has the air assist cylinders that will be your problem

Pull the manifold yourself, I’ve pulled many and maybe one bolt broke. On the other hand nearly every time I pull an egr valve one will break. Anyway pull the manifold, take it to a machine shop and they’ll get it out or drill and tap the hole

I've pulled the differential pressure sensor and used a small drill bit by hand to remove the carbon buildup in the two ports in the mounting bracket , when I figured I have cleared the mounting bracket I took a spray nozzle straw and pushed it into the venture

Yes it has a/c the new fan clutch is on at all times with the harness to the clutch disconnected. I’d really like to see the diagram if it shows wire number and numerical pin placement

clamp off the heater hoses and see if that helps

Wondering if someone could post a diagram for the fan clutch? It looks like at some point a belt broke and tore the connector off the engine harness. I guess the clutch finally got tired of staying engaged at all times. I’ve replaced the clutch, now thinking I can hard wire the new clutch or try and obtain a new connector but the wires are all the same color with numbers on them. The boss don’t want to by a harness for one connector. Thanks

Had one doing this before but I can’t remember what the problem was. I’ve reprogrammed with the latest software. It will not get over 360deg on regen and never starts dosing. The engine sounds like it’s going into fuel cut or missing. Checked all exhaust temp sensors, VGT function and I believe the EGR is working properly. Fuel pressure is good. The status read purging air the whole time. I haven’t checked but maybe the doing module is spraying a butt load of air into the exhaust? It won’t set any DTC’s . It runs fine though. It has the turbo bypass but non functional when regening.

Will do. I've had many clear out after a parked regen. Maybe this particular one's software won't allow it.

I have a 2012 chu613 with an MP8. I have a fleet ranging from 08 to 14. I'm working on one with a spn 4094-1 dtc and the guard dog states evaluating def quality 5mph derate temporarily off continue driving or something like that. It has new nox sensors, dosing module, nozzle and air regulator back by the air drier. I've cleaned and tested def dosing unit and replaced def filter. On tech tool when choosing what system I have while going to regeneration screen it asks mp8 us 10 and mp8 without turbo bypass. I've tried both settings and can't get the dtc to go inactive. It seems that the temps are getting to normal range on both. But on mp8 us10 it shows turbo bypass and the green light never comes on. What I'm unsure about is, I have some with the dosing module on the left side of the engine with and without the bypass valve. I'm not sure if the bypass is suppose to activate on this one or maybe needs a software update.

pretty sure it did, its been on the road for a month. I also put new orings one the injectors

The latest design cup installer pushes a teardrop shaped piece down through the cup tip and then pulls it back through. I've never seen a puller like that.

Mack calls it an “overflow “ valve

I'm pretty sure its fuel anyway. I found it while replacing the oil cooler cover, coolant was pouring out the bottom at the front of the engine. It already had the updated cover with metal gasket. I noticed after removing the cover the rectangular rubber gasket where the cover butts up to the rear of the water pump housing was torn and swollen. At that point I pulled the thermostat and the rubber gasket was gone. Anyway I replaced all of the coolant oring seals, they all fit loose and some looked like a rat had been chewing on them. Now I'm replacing the cups and Injector orings. The engine ran fine and the injectors look real clean. I really don't see any bad orings on the cups or injectors. The injectors have two orings on them so assume that are original. I guess I should go back with just the one oring on the injectors like the new ones come. I anyone has anything to add or anything else I haven't considered please chime in. Thanks

If the regen switch is in the inhibit (down) position it will derate the engine also.

Thanks for the pic's. really useful. fuel pressure is good btw. I guess I need to make a clear hose to attach where overflow valve goes down to the filter housing.

When the engine runs fine with no load but starts fluttering at 1250 rpm loaded I usually replace cups and injectors. Just wondering if I could get away with just installing cups.

May be programmed that way

Got the ground problem fixed T1 at 275 or so

I working on a 2012 chu613 with an mp8. Its equipped with the hydrocarbon dosing module and turbo bypass valve. The regen light was flashing 88% soot level. when attempting regeneration the dosing vale status is 0% and purging air, fuel pressure is 65+. I put a new dosing module on because I had one doing about the same thing and it took care of it. now for the weird stuff. while I was regening I noticed the battery voltage was 14-16.5 volts. I was thinking the system may be malfunctioning due to the high voltage. So if figured I would disconnect the alternator and try with just battery voltage. Got back in the cab and had no power to anything. no lights flashers or anything. while inspecting with my power probe I touched the ground side in the power outlet and it detected 12.5 volts. Just for kicks I hit the ground button on my probe while touching ground of the power outlet heard a relay click and everything powered up of a second or two. hit the ground again it powered up again and stayed on. Started the engine and tried to regen but still have the same problem with just purging air. Any ideas about whats going on?

Pulled the injectors and the original copper cups. Didn't see anything out of the ordinary with the cups, all looked about the same. I'm going to go back with new injectors and cups. Hope this takes care of it, I dont want the boss to loose faith.

Gonna pull the injectors Monday. I guess if it has stainless, I’ll change just the cups. If there copper I’ll put in a six pack. The engine runs fine other than on cold start it has a little rough idle for about three seconds which my be a little coolant in the suspect cylinder

It’s black and the tank is new