Compression check

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by Salvage 1, Feb 22, 2019.

  1. Salvage 1

    Salvage 1 Bobtail Member

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    To help determine the need for an overhaul or the extent of the overhaul what should the cylinder pressure be on a 3406e 6 TS
     
  2. Goodysnap

    Goodysnap Road Train Member

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    Off the top of my head, dont recall ever seeing a published compression number for CAT. Some of the more experienced CAT guru may prove me wrong...............but

    Generally speaking you will need to be in the 350-550psi range for adequate combustion. If you have a way to measure it, that is.
     
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  3. Salvage 1

    Salvage 1 Bobtail Member

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    Well yea remove injector use correct adapter and compression guage 350 to 550 is allot of range ??I have allot of white smoke at start up even if its 30 degrees.. And some running bobtail at take off..white smoke is unburnt fuel either really low compression or injectors slobbering overfueling
    Trying to figure out
     
  4. spsauerland

    spsauerland Road Train Member

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    Cat has always said compression test #'s are no good on engine with keystone cut rings. Best to see if one is lower than others or do a cylinder leakdown test.
     
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  5. Goodysnap

    Goodysnap Road Train Member

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    Run cylinder cutout when stone cold to see when smoke clears to pinpoint offending cylinder. Swap injectors with a good clean one to see if it moves. If you have a cylinder issue, its teardown and inspect time. If you have one marginal or head gasket issue, others will be soon to follow. Pointless to tear it down to fix one hole.
     
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