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I have a 3406b with alot of blowbye whats the problem

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I take it that you are meaning a caterpillar diesel 3406 b 6 cylinder engine. By blow by I take it that you mean smoke from the vent pipe connected to the rocker cover or the plate on the side of the engine. Excessive crankcase pressure (blow by) comes from the high combustion pressures passing the rings (worn rings/broken rings damaged bore) and going to the sump. It also comes about if the bores are glazed up from excessive idling at no load using incorrect injector settings. Glazed bores may be from using a multi grade oil instead of a single grade oil.. Have a compression test done to check engine condition

Posted on Jul 27, 2013


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I Have a 3406b cat engine in a truck that has a misfire. I have reconditioned the pump and injectors, the engine idles smoothly, however when you increse the engine revs ,there is a misfire . I have not...

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