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What would cause an engine to lock up besides valves? (Re-Timing)

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Old 05-12-2008 | 04:03 PM
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Default What would cause an engine to lock up besides valves? (Re-Timing)

Was rotating the engine after initial tensioning of the timing belt, as per instructions. It's locked up and will not move clockwise or counterclockwise, even with significant torque applied to the crank bolt- more than I remember ever needing to turn the engine in the past.

Had engine set to TDC #1 (OT on flywheel, cam gear set to notch in cover) before removing anything timing related. Had locks on the engine 98% of the time, but my out-of-engine flywheel lock may have moved the crank +/- a tooth. Had the oil pan off before to reinstall the pump, and was going to do the rod bearings and pan gasket after finishing the front-of-engine stuff. Therefore, I set TDC by visual inspection of the #1 piston, and centered the rod cap with the crank at the top of the stroke. Again, the cam was at TDC for 1- I did this right. There is absolutely no way that I rotated one part 180 or 360 degrees relative to another part. I set initial tension to 3.7 on the 9201, and started turning.

Rotated the crank about 30 degrees and I'm in my current predicament. The cam kept time with the crank. I don't think I'm against valves, because 2 and 3 are relatively close to the bottom of their strokes, and 1 and 4 are in the process of moving downward. I would think if this was the case, the engine would turn CCW and go back to TDC- this is not the case. Any ideas?

Spark plugs are out, no transmission to lock the engine, no lock installed, and it's much cleaner than it looks in my avatar. Thanks.
Old 05-12-2008 | 05:49 PM
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If it was turning before, and you can't turn it now, sounds like something got damaged, no?

Maybe you can try removing the drive gear on the oil pump to see if it's locked up (since you said you installed the 'pump' -- I assume oil pump).
Old 05-12-2008 | 09:47 PM
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For future reference, make sure the crankshaft timing belt pulley is installed with the lip facing out.

Turns beautifully now.
Old 05-13-2008 | 03:32 AM
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at least it was something simple and none destructive. good luck with the rest of your work.
Old 05-13-2008 | 03:43 AM
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Make sure the washer between the crank timing gear and the oil pump drive is there or you will have no oil pressure.
Old 04-04-2011 | 10:28 AM
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Would motor lockup if timing belt brakes on gl1100 gold wing.
Old 04-04-2011 | 11:39 AM
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I had a small screw once that got lodged under the refeference senson. Seriously. Couldn't turn it by hand. Thought I broke a crank so we pulled the engine.
Old 04-04-2011 | 12:20 PM
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Originally Posted by yellowline
For future reference, make sure the crankshaft timing belt pulley is installed with the lip facing out.

Turns beautifully now.
I was going to say this... Did a t-belt job last weekend and the same thing happen.... for the same reason! Ha ha Glad you figured it out.
Old 04-04-2011 | 02:37 PM
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Here is a story for you. I had to a clutch job on a high mileage car and when I tried to rotate the engine to put the clutch cover bolts in it wouldn't go all the way around, turn the other way and it would stop in the same place. WTF!!! Very long story short when I finally pulled the head I found that when I pulled the exhaust, the carbon build up fell into the cylinder and since there is no clearance on that side of the head that wad of carbon stopped it.



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