Need some advice from experienced folks. I ended up with an old American truck powered by a Mack E7 engine that had been sitting idle for a couple of years. I decided to bring it back to life for work in a quarry, but I’ve run into an issue: the engine started producing bluish smoke and isn’t holding oil pressure very confidently when hot. I understand this might be heading toward a full overhaul, but I really don’t want to dive into the piston group blindly without exact specs for clearances and cylinder head bolt torque values.
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Mack E7 issues, looking for overhaul manual
- Thread starter Carla22
- Start date
Guys, could anyone point me to where I can actually find proper technical documentation these days? I need something detailed to go step by step through crankshaft inspection and valve adjustment. The notes from the previous owner look more like greasy scribbles than a real guide. Also, are there any specific nuances with installing cylinder liners or a particular tightening sequence for the main bearings that aren’t usually mentioned in general advice? Maybe someone has a reliable manual with full specs, including piston protrusion tolerances?
I'm no expert, but I get it. Bluish smoke and low oil pressure are often caused by long periods when the engine is not being used. One of the reasons behind the piston rings being stuck or valve stem seals getting degraded. You seem to know about clearances, these cannot be assumed, especially when it comes to tightening the cylinder head, otherwise the gasket will get blown within a month. Actually, when I did my engine rebuild of a Mack E7 engine, I took help of ManualMachine website, which has a very informative service manual for MACK E7, E7 Overhaul. Also, when dealing with liners, you must check the seating areas on the block for cavitation, as this is a typical problem of these engines. Besides that, one thing I would say is that you shouldn't try to save money on the bearings. And, have you managed to dismantle the oil pan already and checked the oil pickup screen?