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Porch Pup
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About steeler

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  1. steeler

    mack 18 speed problem

    Damn. You don't see sliding clutches worn out in a Mack trans very often. They can take a lot of abuse and still function just fine. Unless someone was VERY abusive to it, or whoever looked at it doesn't have much experience diagnosing them.
  2. steeler

    need help with 4-2 blink code please

    No problem. Glad you fixed it!
  3. steeler

    MP7 engine

    Good catch. I should have said fmi 3 or 5. Not 7. Thanks.
  4. steeler

    mack 18 speed problem

    Just curious, how much did you pay for that reman? If your problem was the syncro, that could have been done much cheaper. I don't know what idiot told you that you had 6 syncros in there, but stay away from that guy.
  5. steeler

    MP7 engine

    What is the fmi on that code? 5 or 7? Could be that it needs the new style pins in the harness.
  6. steeler

    Mp8 valve adjustment problem

    I just pulled the rocker back loose and switched 4 and 5 plungers. Everything looks perfect now. I don't know why that plunger doesn't like being in number 4, but it all adjusted up just fine now.
  7. After an injector cup job, while adjusting valves, the plunger on #5 exhaust valve is sticking out a little more than the others. All others adjusted fine, but#5 has a much thinner shim under it, like someone had this issue last time. If I push down on the rocker arm, three is a little spring loaded feel to it, not anymore than the others had. Any reason this plunger is sticking out further?
  8. steeler

    need help with 4-2 blink code please

    Pin number 9 at ecu connector j1(the top one) is your ground signal to turn fan off. Before you start splicing, check that wire for continuity to the fan solenoid.
  9. steeler

    need help with 4-2 blink code please

    Yes, if you aren't getting the ground from ecu, I ran a new wire from eco to fan solenoid. My daughter was sick this morning so I stayed home today, but I'll get the info in the morning.
  10. steeler

    need help with 4-2 blink code please

    You should have a constant 12v at one wire of the fan solenoid, the other wire is a ground signal from the ecu to disengage the fan. It could be as simple as a blown fuse (don't quote me but #41 I think?) Or could be a break in either the hot wire or ground. I've seen many that were broken wires, rather than chase the mess around and on top of the transmission, I just rewired, bypassing part of the harness. I don't have a schematic with me right now, but can give you pin numbers Monday if you still need them.
  11. Mine does not have the separate pump for after treatment, but I found the problem. The 7th injector was plugged up. Mack needs to fix some issues with the guided diagnostics in tech tool, it never mentioned anything about that as a possibility for the code I had. Oh well all good now. Thanks.
  12. Ok hooked shop air to the shutoff valve, that didn't change anything. So if my test vehicle has after treatment fuel pressure of 90, with engine fuel pressure at 60, what "ups" that pressure? I thought after treatment fuel pressure would be equal to engine fuel pressure?
  13. I was wrong on that test, all it was was checking the fuel pressure to the shutoff valve, which is the same as the engine pressure. That was the last test, so it just told me "no fault found". I hooked up another truck of the same year just to compare pressures. That one had an after treatment fuel pressure of 90 psi when the shutoff valve opens, then dropped to zero with the valve closed. Mine stays at about 45 with the valve closed. I'm going to run regulated shop air to the shutoff valve at 32 psi just to see if anything changes.
  14. steeler

    Mp8 boost question

    Do you still have active dpf codes? Could be derated causing your low power?

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