Gentlemen,Finished reassembly of 1987 AQ 131A and 275 drive. Set timing by finding TDC on No 1 piston and placing temporary mark on pulley. Existing hash mark seemed way off. Engine runs and idles well. Upon lossening pulley bolt found it spins freely as if not keyed to crank shaft. Upon removal found a weird setup. Crankshaft end has noraml keyway along its length as you would expect. However, pulley/damper does not have a key way on it length but on the front end with key that appears to get sandwiched under the large washer/bolt. The key was only 1/4 inch long and was not engaging the crank shaft slot, thus the pulley spinning. This key is more like a pin even tho it is shaped like a key.
Don S. or others,
Can you provided me some guidance as I have never seen a key setup like this. I have looked at the diagrams on Marine Parts Express for the crankshaft parts listing on a AQ 131A and the pulley/vibration damper appears as part number 855476 with a cost of $2661.12 which is insane. It does not list any key and the engine manual that I have does not show any of this detail.
The pictures show the dampener with the key which is about 1/4 inch long that I found installed. You can see the keyway is on the front face not along the circular diameter as normal.
Regards
Paul
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