C12 problems.

Discussion in 'Trucks [ Eighteen Wheelers ]' started by Pursy, Jul 11, 2019.

  1. Pursy

    Pursy Bobtail Member

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    I have a 2006 Cat C12 covered 500000 miles. Recently noticed moisture in the breather pipe. Pulled a valve cover and its the same story. Its using nearly a gallon of coolant in 1000miles. Been keeping an eye on the temp and oil pressure on the CAT ID as I have no oil gauge and thats down to 26 ibs running and 12 ibs idle. Yesterday I felt the Jakes were losing their effectiveness .Verified this with a mechanical gauge too. I have also pressurized the cooling system to 14 ibs and pulled the pan and cant find any internal leaks. Can this be 1 thing like a cracked head giving me this problem or has my luck gone bad?
     
  2. ibcalm19

    ibcalm19 Road Train Member

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    The coolant is going somewhere you have to find that leak. The oil pressure is to low. You're going to have to do some diagnostics. Your motor is telling you that now. I wouldn't continue to run it with those problems. All the best to you.
     
    x1Heavy and Opendeckin Thank this.
  3. Opendeckin

    Opendeckin Medium Load Member

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    Could be a motor headgasket or cracked head. It could be the head gasket on the air compressor too. Could also be be a broken oil cooler.
     
  4. spsauerland

    spsauerland Road Train Member

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    Could also be water pump.
     
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  5. Pursy

    Pursy Bobtail Member

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    Had a couple of hours on it today. Had the oil pressure relief valve out. Its got some scuff marks on the plunger but unless I strip the filter housing off I cant tell what the bore is like as the chassis wont let me see in the hole. Had the valve covers off to see if there was a cracked Jake housing or loose solenoid again it all looks nice.
    Thanks for your replies so far.
     
  6. Intothesunset

    Intothesunset Road Train Member

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    Is the c12 or c13 the problem child?
     
  7. Pursy

    Pursy Bobtail Member

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    Bit of an update. Friday the oil pressure was down to 20lbs, I had 2 very local loads to do so did those and back to the yard. Pulled the pan,got the pick up pipe off and had a good check for cracks, next off with the oil pump, the end cap showed very slight wear so that was cleaned and put back together. Pulled no 5 con rod cap and the bearings were decent,put a dial gauge on the crank and end float was .008” so no problem there. I got the oil filter housing off next. Still thought the oil pressure relief valve didn’t slide too well in its bore so I got it in the lathe and polished it up with wet and dry. Put it all back together with fresh oil and filter. Pressure was at 38 lbs tick over on initial start up. I am going to get the old oil sampled. Still have moisture in the oil breather but at least oil pressures back.
     
    x1Heavy and Intothesunset Thank this.
  8. x1Heavy

    x1Heavy Road Train Member

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    If it is the water pump, shut it off and wait until morning. Should you discover a lake at sunrise...
     
  9. x1Heavy

    x1Heavy Road Train Member

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    Have you considered a snake light? A micro LED at the end of a thin tube could get into all sorts of wonderful places, particularly if you can transmit the image to lap top etc.