STUCK 6.2L MPI

chrisrankin

Cadet
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Jul 15, 2009
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6
My boat sat for a couple of years during Covid. I changed the oil and primed the engine without starting it. I pulled the plugs and fogged the cylinders with oil. Later, I proceeded to try and turn the engine over by hand at the crank pulley. I would apply approximately 50lbs of force on a 18" torque wrench and then ease off and I continued to do this for 4-5 times until the engine broke free. When the engine did break free I heard a "ping". I would assume this noise came from a piston ring, although I don't know that for sure. I would like to hear anyone's thoughts on the matter.
 

alldodge

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A noise is hard to determine, but if a ping would break, I don't think you would hear it. Might have been the noise from a pulley
 
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dubs283

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You didn't check fluids, hook up the battery and try to start normal?

Sounds as if you forgot procedure and assumed the worst, turning engine over by hand after two years sitting?
 

Scott06

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Apr 20, 2014
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My boat sat for a couple of years during Covid. I changed the oil and primed the engine without starting it. I pulled the plugs and fogged the cylinders with oil. Later, I proceeded to try and turn the engine over by hand at the crank pulley. I would apply approximately 50lbs of force on a 18" torque wrench and then ease off and I continued to do this for 4-5 times until the engine broke free. When the engine did break free I heard a "ping". I would assume this noise came from a piston ring, although I don't know that for sure. I would like to hear anyone's thoughts on the matter.
You sure the engine was locked up? would think the gimbal bearing or u joints would be a likely culprit especially if water was in bellows.
would be worth pulling the drive to check them given what you are describing
 

chrisrankin

Cadet
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Jul 15, 2009
Messages
6
You sure the engine was locked up? would think the gimbal bearing or u joints would be a likely culprit especially if water was in bellows.
would be worth pulling the drive to check them given what you are describing
It wasn't locked up.
You didn't check fluids, hook up the battery and try to start normal?

Sounds as if you forgot procedure and assumed the worst, turning engine over by hand after two years sitting?
LOL
Its an inboard with v-drive and prop shafts.
 

Scott06

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Apr 20, 2014
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It wasn't locked up.

LOL
Its an inboard with v-drive and prop shafts.
Hard to know that unless you tell us…you intimated that you had to force the engine to turn over with a large torque wrench… so it spun freely you just wanted to see how much torque to turn over.

is compression ok only other thought on hearing a ping is if a valve is hung up.
 

chrisrankin

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Jul 15, 2009
Messages
6
I understand
I don't know. It just bothered me when I heard a ping, although I have seen guys on Youtube with 4ft cheater bars and hitting the starter at the same time in order to break a stuck engine free, which seemed crazy to me, but they got them running and they didn't smoke afterwards.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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I don't know. It just bothered me when I heard a ping, although I have seen guys on Youtube with 4ft cheater bars and hitting the starter at the same time in order to break a stuck engine free, which seemed crazy to me, but they got them running and they didn't smoke afterwards.
Idiots post on facetube all the time. A 4-foot cheater will strip the threads from the crank rendering it junk. If a motor is stuck from rust, it will smoke if they get it running

Always use a crank socket to turn a motor from the crank snout
 

tpenfield

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Jul 18, 2011
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A 'ping' could be anything maybe the the key aligning the balancer to the crank shaft broke . . . who knows.

Since you had to put a bit of force (torque) on the crankshaft bolt, it may be worth a look at the balancer/pulley.
 
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