Can the crank bolt come loose if using it to rotate the engine?

suspect · 08-03-2023, 10:46 AM

If you use the front crank bolt to rotate the engine with a ratchet, can it come loose or mess something up?

HondaRC51 · 08-03-2023, 12:59 PM

Nope, as long as you are spinning it in the correct direction of engine rotation you wont harm anything. And don't use any impact guns or you might over torque or loosen the bolt.

Edit: pull the spark plugs out to rotate the crank much easier so you aren't fighting the compression!

suspect · 08-03-2023, 02:35 PM

Quote:

Originally Posted by HondaRC51

Nope, as long as you are spinning it in the correct direction of engine rotation you wont harm anything. And don't use any impact guns or you might over torque or loosen the bolt.

Edit: pull the spark plugs out to rotate the crank much easier so you aren't fighting the compression!

Is the direction of engine rotation clockwise? How easy is it to loosen the bolt if done anti-clockwise?

TheMidnightNarwhal · 08-03-2023, 02:45 PM

Technically it could loose going anti clockwise but I doubt it would happen with how tight it is. But to be safe I only turn it clockwise.

suspect · 08-03-2023, 02:59 PM

Quote:

Originally Posted by TheMidnightNarwhal

Technically it could loose going anti clockwise but I doubt it would happen with how tight it is. But to be safe I only turn it clockwise.

Car is going in for walnut blast next week so it won’t be me working on it which is why I was wondering how easy it is to loosen the bolt in case it was spun anti clockwise to adjust the valves. And if there is anyway to make sure the bolt is not loose after.

TheMidnightNarwhal · 08-03-2023, 04:05 PM

Quote:

Originally Posted by suspect

Car is going in for walnut blast next week so it won’t be me working on it which is why I was wondering how easy it is to loosen the bolt in case it was spun anti clockwise to adjust the valves. And if there is anyway to make sure the bolt is not loose after.

Oh ok. You could try making a line as straight as possible from bolt edge to the pulley face. If it's mismatched after that you'll know.

suspect · 08-03-2023, 04:10 PM

Quote:

Originally Posted by TheMidnightNarwhal

Oh ok. You could try making a line as straight as possible from bolt edge to the pulley face. If it's mismatched after that you'll know.

Great idea. Thank you.

Serf27 · 08-08-2023, 03:16 AM

Bring this issue up with whoever is doing the work.
They will know and should be responsible if anything gets loose.
Draw a line as suggested and check it afterwards.

suspect · 08-08-2023, 02:46 PM

Quote:

Originally Posted by Serf27

Bring this issue up with whoever is doing the work.
They will know and should be responsible if anything gets loose.
Draw a line as suggested and check it afterwards.

Tried drawing lines, turned out to be smudges so unless its a big misalignment it might not show.

Serf27 · 08-08-2023, 02:58 PM

Explain the concern to who is doing the work.
I’m sure they’ve done it before if they’re doing it for you and they should know what they’re doing.

08-03-2023, 10:46 AM	#1
suspect .******. 44 Rep 226 Posts Drives: car Join Date: Apr 2023 Location: location iTrader: (0)	Can the crank bolt come loose if using it to rotate the engine? If you use the front crank bolt to rotate the engine with a ratchet, can it come loose or mess something up?
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08-03-2023, 12:59 PM	#2
HondaRC51 Private First Class 253 Rep 125 Posts Drives: 2009 E92 335xi Join Date: Oct 2022 Location: Maryland iTrader: (0) Garage List 2016 BMW S1000RR [10.00] 2009 335xi E92 [0.00]	Nope, as long as you are spinning it in the correct direction of engine rotation you wont harm anything. And don't use any impact guns or you might over torque or loosen the bolt. Edit: pull the spark plugs out to rotate the crank much easier so you aren't fighting the compression! Last edited by HondaRC51; 08-03-2023 at 01:00 PM.. Reason: added info
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08-03-2023, 02:45 PM	#4
TheMidnightNarwhal Major General 2821 Rep 6,394 Posts Drives: 11' 335is DCT Join Date: Jun 2015 Location: Gatineau, Quebec iTrader: (0)	Technically it could loose going anti clockwise but I doubt it would happen with how tight it is. But to be safe I only turn it clockwise.
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08-08-2023, 03:16 AM	#8
Serf27 Brigadier General 2887 Rep 4,333 Posts Drives: 335i Join Date: Apr 2018 Location: Sitting in a BMW. iTrader: (-1)	Bring this issue up with whoever is doing the work. They will know and should be responsible if anything gets loose. Draw a line as suggested and check it afterwards.
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08-08-2023, 02:58 PM	#10
Serf27 Brigadier General 2887 Rep 4,333 Posts Drives: 335i Join Date: Apr 2018 Location: Sitting in a BMW. iTrader: (-1)	Explain the concern to who is doing the work. I’m sure they’ve done it before if they’re doing it for you and they should know what they’re doing.
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