Over torqued crankshaft hole cap

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I use an impact driver and rubber hammer to get those sorts of caps out. The impact seems to help free them and also ensures the tool bit is driven into the hex head firmly while you do it.
 
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I use an impact driver and rubber hammer to get those sorts of caps out. The impact seems to help free them and also ensures the tool bit is driven into the hex head firmly while you do it.
If you don't grease the plug, that dry rubber grommet will grab the metal and make loosening difficult. I had an aftermarket screw in gas cap on my ST (Oberon, I think was the brand) and it too had an O-ring. If I tightened it just a bit too much it was dang near impossible to loosen. A tiny dab of silicone paste took care of that until the gas washed it away.
 

Igofar

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There is a second, and I think more probable cause for the difficulty you encountered when trying to remove that crankshaft hole cap: The last person to remove and replace it didn't pay attention to the fine print in the Service Manual, which states "Apply Grease to the Threads".

I went into the Service Manual to find the torque for that cap and the little timing hole cap above it, and saw the "Note 7" beside each torque value. Note 7 says "Apply Grease to the Threads".

The torque values for both of those caps are extremely low. I guess, though, with a new O-ring installed on each one and grease on the threads, the very low torque is sufficient, because I can't ever recall seeing a post where someone has complained about oil leaks from either of those plugs.

Michael

Service Manual Specifications - Timing Hole and Crank Access Hole caps
Grease on threads.jpg
Now this young man was paying attention in class :thumb:
This is why Michael would be one of the very few folks I would trust to work on my equipment, or I would trust him flying me somewhere.
Thanks for posting this.
:WCP1:
 
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687
one might also ask why a trivial fastener like that, which basically plugs an access hole and nothing more, would require someone to read through the service manual to be able to properly re-install it to prevent damage to the fastener the next time its removed.

Seems more a case of the Honda engineers not paying attention in class the day "keep it simple stupid" was being taught.

The cover on the 1100 was designed for the same purpose, uses regular 6mm bolts with 10mm hex heads, and requires no lubrication to ease in extraction the next time around. Somebody tried to save a few pennies on the 1300 by fixing something that wasn't broke, and did a lousy job of it.
 
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mjc506

Matt
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I recently had the same problem on my new-to-me '02 ST13 (not ridden yet, going through the excellent maintenance checklists) Rather the mess something up trying to remove the stuck cover, I instead put the bike in 5th and turned the rear wheel (forwards!) to turn the engine. Not as easy as using the crankshaft bolt (repeatedly walking to the back and front of the bike trying to line up the timing marks gets tedious) but it worked!
 
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20230708_142802.jpg

I just freed mine, thanks to this thread.

I tried Kroil and ACF-50, but it was stuck fast. I left the cap in place, moderately chewed up, to leave on a planned tour. ~3,500 miles later, I went at it again, harder, and it finally came free.

20230708_153610.jpg
The o-ring and threads look to be in great condition. I doubt that Kroil or ACF-50 could creep past the o-ring, so I'm guessing that they did nothing. *Or* the ACF-50 did creep past and dissolved corrosion, as advertised! (Unlikely, IMO)

Maybe it helped that I was running the engine to get it fully warmed up. If it hadn't come loose by the last chisel strike, my plan was to spray the cap with CRC Freeze-Off. That may have helped if it was corrosion, but I don't know if it would have helped if it's all due to the o-ring sticking... Could Freeze-Off help in a simple over-torque situation? Maybe.
 
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