c-mac

I have an 08 Pinnacle chu mp8 . when running the the secondary air pressure is 150psi on the gauge and the warning light on the gauge is on. with the engine off I can bleed the tanks and pump the brakes until there is no air. and sec air only drops to 50psi. either there is a sensor that I dont know of bad or the gauge is bad. the gauge is built into the cluster assembly. There has to be a sensor somewhere. can you help? I have no manual!

Thanks man, you're a lifesaver!

does anyone know a link to the bulletin? I have the parts to fix it but cant remember the hook up.

that got it! thanks

First off I have Vcads tech tool, Now, I have a 2011 Pinnacle with an MP8, the regen switch is flashing. It has a DTC -SPN 5443 Aftertreatment 1 hydrocarbon dosing system FMI7 mechanical system not responding properly. I hooked laptop up and to start regen so I can monitor temps and such. Before I could start the regen I noticed the aftertreatment fuel pressure was 101psi, engine fuel pressure is 55psi. not sure how that can be. When fuel dosing started the pressure dropped to 70 or so. Also this particular truck has the "aftertreatment module" and a hydrocarbon doser. Nearly all the trucks in our fleet have the 7th injector unit mounted to the exhaust. I'm not sure if this setup works a little different than what i'm used to. I started regen and the inlet and outlet temps didn't heat up like I think they should, about 600deg after plenty of time dosing fuel. I pulled the dosing nozzle from the exhaust, cleaned and ran test. Nothing cam out, I had pressure, it started blowing out where the fuel line screws on. I just didn't have it tight. If it was't for the high aftertreatment pressure I'd say the nozzle is just clogged. I think that i'm going to order that dosing nozzle. what do ya'll think?

Injectors, also check for bubbles in the fuel tank while running

Thanks man! You saved my butt.

Just finished replacing cups and injectors in an 08 MP7. Now about to run the overhead. Its is stamped different than the MP8's I have done. an 8 would have 3 E 4, #3 intake and injector, # 4 exhaust. This 7 says 3 V 4. is this the same? Also do you line it up by the the first number that appears to have a line through it or the line after the last number? 3 V 4 l example. couldnt make a line through the 3. Oh and one other thing, Is the adjustment for the injector, screw center bolt down until contact then tighten 4 flats and tighten jam nut, Iike an MP8?

thanks I got the correct 8.5mm tap from mack. I have the rest of the kit, the tap was just missing.

Circle with the x in is for shutdown override.

I just pulled the 6 copper cups from an 07 MP7. The last one left the tip in the head. I was using the puller that grips the larger area inside the cup. I have replaced many sets of stainless cups on mp8's. Any ideas on getting the piece out? I have the correct Mack tools to Install the new stainless cups for an mp8, Do you use the same tool to swedge the stainless cup in the mp7?