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Short block rotating assembly resistance

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Now that I have the short block assembled, I was wondering what I should be expecting for resistance when turning the engine 4Cyl, 2.3L.

From my understanding, the rings create the most significant drag (on a freshly honed engine) and currently I cannot spin the assembly by hand on the front crank bolt. But can do so with at most 10ftlbs with a ratchet when the pistons are not at the end of the stroke.

I may be asking a silly question that is difficult to give a written answer on, but I have already found machining mistakes made on this build and just want to be sure. So any information would be appreciated.

Hi Philip,

Yes, you should expect to feel some resistance because of the piston rings being in contact with the bore. The term "turning it over by hand" means being able to turn the engine with a ratchet or any other tool that aids you in turning the engine. I would say 10ftlbs is not a lot of turning torque required for a freshly built engine and this sounds to me that the engine is turning freely. Which problems have you already found I would be interested to know as this might change my judgment.

Thanks for the reply Brandon.

The problems I experienced were with main bearing clearances and valve lash due to machinist assumptions. I have corrected those already. i brought it up as I have never build an engine before and the mistakes I have found made it very clear that I need to check the machinists work.

There is a lot of detail on my "learning experience" in the Crankshaft polishing thread that I made in this section of the forum. I do believe you have answered my question though.

Thanks!

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