MP-8 Engine question

Discussion in 'Mack Forum' started by Smurf, Feb 11, 2012.

  1. Smurf

    Smurf Light Load Member

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    I drive a 2011 Pinnacle with the MP8 in it. Just spent a week in the shop for bad running. After the 3rd day and a zillion tests the shop says the #3 and 4 injectors and cups were bad. #4 had separated into 2 parts. Got those replaced and on the first refire it ran like crap but in about 20 mins it smoothed out. Couple of questions.

    1..What would cause the injectors to separate and the cups to leak?
    2.. Oil pressure normally runs 60 psi or better but after about 300 miles it started to bounce around the 35 psi and back. Would stay level at 60 for awhile but did notice the drop back and forth. This was at tip end with the cruise on and flat ground

    I didn't get the chance to ask the mechanic cause after 6 days I just wanted the hell out of there.
     
  2. Mack427

    Mack427 Medium Load Member

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    mp8 had problems cracking injector cup, i heard there was a service bulliten out for it don't know what shop you ended up in but a week down sounds like a bit too long to me
     
  3. Smurf

    Smurf Light Load Member

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    I was at the Mack in Austin Tx. It was so much them as it was the the factory. Started out as knock sensor in Texarkana. They just put the sensor on and say ok its fixed. No road test. Austin put the machine to it but never coded but they could hear the miss and the engineers had them go through hoops with tests before it they said enough and started looking at other things. I got stainless cups and they said its the first time they've run into any issues with those type. Had rust on the number 3 and my guys said pull all and thats when they found number 4 in two parts. its running great its i'm concerned with the oil pressure acting that way. Run it till it blows lol
     
  4. Pablo-UA

    Pablo-UA Road Train Member

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    MP8 is D13 engine! The valve cover differs! It is just red colored volvo engine!

    Pay more attention that Volvo, Renault, Mack, Sisu share powertraine. M-drive is the I-shift. Smaller D9 engines are really Deutz with Volvo/Renault/Mack label and made by Motorolla ECM for Volvo Powertrain.
     
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  5. Pablo-UA

    Pablo-UA Road Train Member

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    Do you really think Volvo only makes engine with different brands? ouh no. Mercedes OM471 CRD is called Detroit Diesel 13/15/16 engine in the USA, Paccar engines in small KW and DAF trucks are all ISB/ISC/ISL with Paccar Label, International Maxxforce is MAN D28 with MAN PM-Kat catalistic converter, Scania shares XPI and HPI parts with Cummins, so not so many engines really.
     
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  6. Mack427

    Mack427 Medium Load Member

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    yeah both motors are built at the Mack Hagerstown powertrain plant, diffrent files in the ecm is the only difference however Mack has been able to keep there's running alot better than the volvo boys D9 same as duetz I'd take one in a heart beat duetz has the bst 4cly and 6cly air cooled irrigation power units in the market place
     
  7. Pablo-UA

    Pablo-UA Road Train Member

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    new Deutz engines in small Volvo trucks (FL, FE) are all CRD. engines are really good, widly used in Ukrainian built buses. I compared Deutz with Cummins ISB and Cat C7, and I'd say CRD is anyway better Cat HUI system, yep fuel sencetive but better for low temperature use.

    It is true that early D13 had local overheat problems with bad injectors and damaged valves, but Volvo Powertrain solved this problem in a year. European and NA D9B and D13 had this issue, fortunatly not D11 and D16
     
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  8. Mack185

    Mack185 Medium Load Member

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    The cups are brass and pressed into the head, leaking coolant into the combustion chamber has been a semi common issue. I'm guessing it was probably getting tough to start wasn't it?

    Just prey you didn't get one with cam issues, those are a nightmare. Even though it is an overhead cam the valve adjustment takes a rocket scientist to do.
     
  9. Pablo-UA

    Pablo-UA Road Train Member

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    brass cups must be properly installed with tool that extracts ends.

    Old cups really loose coolant.
     
    Last edited: Feb 16, 2012
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  10. Sisulogger

    Sisulogger Bobtail Member

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    Sisu was combining Volvo engine with eaton fuller transmission or zf standard manual. Optional was allso allison automatic transmission. Sisu is not using Renault cabins anymore. Nowadays they use Mercedes cabins and engines and transmissions. Optional are allso eaton fuller and allison transmissions for hevy duty use.
     
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