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How hard should a freshly built 13b be to turn by hand?

Old 11-08-21, 10:32 AM
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How hard should a freshly built 13b be to turn by hand?

Hi guys, I've got an s5 13b I'm putting into my car soon and it seems like it might be a little on the stiff side for turning over by hand using a torque wrench without spark plugs or front stack on it. It takes about 25 ft/lbs to turn over. My local mechanic shows about 10-11 on his motors when he turns then by hand.

Is there a spec out there for how hard it should or shouldn't be?

Old 11-08-21, 11:10 AM
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if you're getting 6 pops and it turns smoothly - meaning no notable points where it feels stiffer than others, then it should be fine. for what you're trying to measure, i would imagine there are plenty of variables that would affect it (seals, springs, static compression, lube, etc.)
Old 11-08-21, 11:32 AM
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are the spark plugs in it? if yes, then there will be compression and its harder to turn, you will feel/hear 6 distinct pulses (in fact you should)
if no, then it should spin over more easily, and you will hear stuff coming from the plug holes, but it won't have compression so it should be really even
Old 11-10-21, 09:43 AM
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I have a spare s5 t2 keg I have sitting on an engine stand. I regularly turn it by rotating the teeth of the flywheel by hand without much force except from where you can feel the compression to keep everything free. Spark plugs are in, intake and exhaust ports taped over. Engine was pulled running with good compression.
Old 11-10-21, 09:46 AM
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Is your mechanic comparing only rotary engines or is he comparing piston engines? Piston engines with spark plugs removed won’t have a compression stroke so will feel looser than a rotary.
Old 11-10-21, 12:25 PM
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Originally Posted by DR_Knight
Is your mechanic comparing only rotary engines or is he comparing piston engines? Piston engines with spark plugs removed won’t have a compression stroke so will feel looser than a rotary.
but they have valve springs
Old 11-10-21, 12:54 PM
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Originally Posted by j9fd3s
but they have valve springs
you can tell how familiar I am with piston engines………… lol.
Old 11-15-21, 09:07 AM
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Originally Posted by DR_Knight
you can tell how familiar I am with piston engines………… lol.
lol, i know, they are such silly things
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