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About jwmcgregor

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    Over Drive

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    NW Minnesota

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  1. jwmcgregor

    Lo Volume

    I have 4 2010 CHU613. MP8. I have installed Tire Boss central tire inflation on all 4. All 4 tractors are very slow to inflate the 8 tires up to highway speed pressures. I have the same system on a sterling with 3406B and had them on Pete's with 3306's. The mack/volvo setup is much slower. It's all 4 units so I don't think I have bad compressors. Are the volvo compressors typically lower CFM than the rest of the industry? Could there be something choking flow or creating pressure in the plumbing? Tire boss is plumbed dirrectly into the bottom (wet?) tank. It looks like flow from the compressor goes to the air dryer and directly to that tank. Is it a difference in the air dryer setup? I have noticed that the tractors are slow to air up when we hook shop air to the governor on the firewall. They air up but not like the other tractors we have.. All 4 CHU's are twins and all air up the same way. There are no significant air leaks. There are a couple at the firewall pass through connectors that we can't seem to completely eliminate but they are very minor. Thanks!
  2. jwmcgregor

    VECU Help

    Resolved....The Deutch connector at the firewall (MC??) had threads smeared when it was removed. It did not install together properly as the jack screw did not pull the Deutch connector together all the way. Repaired with tap and die. The molded nut in the deutch connector on the firewall side will spin in its molded housing. Looks like a "be careful spot" Thanks again Challenger!
  3. jwmcgregor

    CHU MP8 Dead outside the firewall

    Resolved....The Deutch connector at the firewall (MC??) had threads smeared when it was removed. It did not install together properly as the jack screw did not pull the Deutch connector together all the way. Repaired with tap and die. The molded nut in the deutch connector on the firewall side will spin in its molded housing. Looks like a "be careful spot" Thanks again Challenger!
  4. jwmcgregor

    CHU MP8 Dead outside the firewall

    Thanks challenger. I’ve taken it apart examined it out it back together. I’ve checked main power relays and all the fuses in both the BEC and the EPDM. I’ve swapped the VECU into another truck to check it out. Everything if ok. I hane not swaped ECM. Unsure if that could be the culprit. I feel like it’s in that MC?? Harness through the firewall but not sure how to prove or test it.
  5. jwmcgregor

    VECU Help

    The iginition relay and EMS relay are passing 12 volts through like they are supposed to. The EMS pre ralay is clicking when the key is turned on. The only relay that is not actuation as it is on the sister truck is the emergency stop lamp relay. I see it connected to the tractor stop lps fuse. That fuse is fine.
  6. jwmcgregor

    VECU Help

    I moved the VECU from the non working tractor into a sister tractor....The VECU worked fine. I have no key to the BEC fuse panel. Was not in the trucks and dealer seems unable to produce one. I've got 12v on both sides of all the fuses in the panel except two. Two have no power at either side but the sister trucks are the same way. Start swapping relays between the tractors? I downloaded some drawings that Mackpro posted. From what i can tell the VECU is the only "smart" hardware in the circuits for the functions that are failing. I can't find information to see if the VECU has power and ground to it. Power through one of the big relays under the dash or power from a relay on the BEC?
  7. jwmcgregor

    VECU Help

    2010 CHU wouldn’t crank to move out of the shop this morning. Drove in to the shop working fine. I see we also have failure of tail lights, wipers, PTO, diff lock, air slide, fuel gauge. I think the datalink is not functioning as well as I can’t connect service tool. The dash powers up and the lightning bolt is illuminated. Fuses are all good. VECU? If so...Are they generic so I could swap one from a sister truck? Thanks
  8. One of my shop guy's installed a new air brake foot valve on 2010 CHU613 MP8 while it's in for winter service. The truck would not crank when we tried to move it out the shop. He disconnected the large square wire harness at the firewall in order to put the foot valve in. The dash powers up. Lightning bolt is on. Starter will not run. The pto/airslide,wipers,rear light's are all non responsive. The headlights at the front on the hood are functioning. A am also unable to connect my service tool now. It's acting like the key is switched off. All fuses are good. I've inspected the harness at the firewall and the wiring to the key switch and under the dash. Don't see any problems. I'm at a loss. Relay or issues with the fireawall connection or harness. I have no diagram of the harness. Ideas or thoughts? Thanks in advance.
  9. jwmcgregor

    Cold Regen

    Thank you!
  10. jwmcgregor

    Cold Regen

    Thanks so much turckster! I'm going to address the EGR valve as soon as I get a chance and possibly swap out the dosing module with one from a sister truck?? and see if things change. Could you explain "adaptptive factor percentage"...This tractor goes from 0% to 100% when doing a parked regen...when it was hot on the road with a load it ran 12% to 25% which is what the other 3 sister trucks do while parked....
  11. jwmcgregor

    Cold Regen

    Took the truck and the load of wheat that was behind it to the elevator with my TEXA hooked up. 97% dpf. A mile or so down the road i noticed the dosing valve was at 100%. Fuel supply psi to after treatment was low..like single didget. Temps did not rise. About 5 miles into the 14 mile trip the dosing valve was operating between 15 and 25% and the fuel psi to the after treatment was 64 psi...primary pump psi was 68 at the time. Temps came up to 900 and 1000 deg. The passive regen continued until I reached the check in. HEST light came on when I stoped. I continued the regen with the blue switch until i needed to move. Dumped the load scaled out and drove back with the dosing valve at 100% and single 1 psi on aftertreatment supply psi. Temps never got over 600 deg empty. Soot burned off to 78%...was at 80% when I reached they yard empty. Is it normal for the dosing valve to be wide open with no fuel psi....wondering if I have intermittent signal from the psi sender on the after treatment side or did it just make enough heat while loaded to successfully "burn"? Any thoughts?
  12. jwmcgregor

    Cold Regen

    Checked it again and caught video...a couple bubbles when first started then nothing...
  13. jwmcgregor

    Cold Regen

    Did the glove test. EGR command was zero and stayed at zero. The glove filled up and blew in about 20 seconds. Is that enough leak to cause my regen problem? Dealer is telling me it's injector cups. I checked the return for air. Nothing when i started the engine..10 sec got a burst of multiple large bubbles....no bubbles for 30 sec...then got a consistent small bubble every 5 sec or so. Thoughts?
  14. jwmcgregor

    Cold Regen

    I have a US7 MP8 in t 2010 CHU. Not spark assisted DPF setup. I've taken care of and have now got no fault codes showing up on the engine. Soot level showed 90%. When I force a regen through TEXA I get a slow clime to about 600 deg on the front side and the back side stays 50 to 55 deg cooler through the process. I am seeing the dosing module status at 100% but no increase in temp. I tested the DRV supply pressure with my thumb at the DRV valve and It builds plenty of pressure rapidly once regen is initiated. I supplied pressure to the DRV valve when i had it removed and it operates smoothly. I find no sigh of leaks. I removed the dosing module, cleaned the tip and initiated a regen. The nozzle immediately puts out three bursts of fuel then nothing so I cancel the regen. The system completes the regen process without any errors but never reaches temps over 600 deg and soot level is higher at the end of the process. I run VGT test and I can hear the actuator traveling through it's stroke and back. EGR position says zero when truck is idling but i can't see it's position while running the regen. Pressure to the dosing module shows similar to pump pressure when the truck is idling but I can't see where it's at while running a regen. Don't know what to do next...Trying to avoid taking it in to the dealer for what seems to be a $2000 minimum fix. I purchased four of these trucks and I'm working through issues with each of them. Love the trucks and the way they are set up...struggling with the emissions stuff. Any Ideas or dirrection? Thanks
  15. jwmcgregor

    MP8 Broken Crankshaft

    Well.. I’m in need of a doner engine for a 2010 chu613 with MP8 415C. DPF not SCR. Can anyone tell me if this 2011is a compatable donor? It is DPF and SCR family ABPTH12.8SOI Serial 938209 Thanks

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