Flywheel not engaging?? Mercruiser

[davecalman]

Hi guys
Would love some help with this?
Brand new battery but the flywheel will not engage. From what I've read on here thinking possibilities could be
1. Bendix in starter motor
2. Starter Solenoid.
3. Seized motor (although have moved flywheel with difficulty and propeller whilst in gear.)
Thanks in advance

 

[stresspoint]

first things first , only if you suspect it may be water ingested seized.

and i say this because trying to crank a seized motor with the starter will damage other stuff.

remove the spark plugs and look for sign of water / rust etc.

attempt yo turn the motor with the bolt on the harmonic balance .
if no go , remove the serpentine belt or drive belt whichever you have .
try again .
if it does not turn chances are water got in.
all is not lost yet , , remove the out drive from the equation and try again .

if it turns over fine you can then start investigating the starter , starter solenoid , wires going to starter etc .

good luck .

 

[nola mike]

.


attempt yo turn the motor with the bolt on the harmonic balance .

Don't do this. Don't know what engine you have, but safer ways to try to turn the mirror over. Unclear from your description whether the starter is engaging the flywheel and then not turning the motor or if the Bendix isn't extending. More info about the motor and history would be helpful

 

[Prophammer]

Looks like a Mercruiser 3.0 , we had one and replaced a bad starter with an automotive starter, the automotive starter would only freewheel like yours sounds, we had to go back an get a marine starter for it, both starters looked almost identical. If its for sure seized, you could spray some WD40 down the spark plug holes and let is soak awhile then try turning it by the crankshaft balancer bolt , if rings are simply stuck to the cylinder you might be ok, just some ideas to throw at you - good luck

 

[nola mike]

Looks like a Mercruiser 3.0 , we had one and replaced a bad starter with an automotive starter, the automotive starter would only freewheel like yours sounds, we had to go back an get a marine starter for it, both starters looked almost identical. If its for sure seized, you could spray some WD40 down the spark plug holes and let is soak awhile then try turning it by the crankshaft balancer bolt , if rings are simply stuck to the cylinder you might be ok, just some ideas to throw at you - good luck

Hah, totally missed that video. Yeah, looks like a 3.0. also sounds like the starter is turning. So new starter time.

 

[stresspoint]

Don't do this. Don't know what engine you have, but safer ways to try to turn the mirror over. Unclear from your description whether the starter is engaging the flywheel and then not turning the motor or if the Bendix isn't extending. More info about the motor and history would be helpful

with the plugs out the motor should turn easy with just a 1/2 inch drive ratchet .
??? what would be the problem with that much torque on that bolt .

FWIW , iv been turning motors over with that bolt for many years """ plugs out "" without ever snapping one off , LMFAO , if that bolt snapped under these circumstances i would not feel safe with regards to the harmonic balancer spinning @5 k rpm.

 

[Bt Doctur]

A well known fact that trying that could result in a sheared nose bolt requiring complete disassembly to repair the crankshaft.
From the video it sounds like the stater motor is good and also the bendix is kicking out to the ring gear. So, if it is water ingested the bendix gear is bad or the ring gear is missing the teeth in that exact area from trying to start the motor. Visually inspect the teeth and starter for rust. maybe the starter was under water and bendix rusted solid

 

[stresspoint]

A well known fact that trying that could result in a sheared nose bolt requiring complete disassembly to repair the crankshaft.
From the video it sounds like the stater motor is good and also the bendix is kicking out to the ring gear. So, if it is water ingested the bendix gear is bad or the ring gear is missing the teeth in that exact area from trying to start the motor. Visually inspect the teeth and starter for rust. maybe the starter was under water and bendix rusted solid

you do know the tightening torque for that bolt is well beyond anything a1/2 inch drive ratchet could put on it without plugs in ..

 

[Scott Danforth]

you do know the tightening torque for that bolt is well beyond anything a1/2 inch drive ratchet could put on it without plugs in ..

the damper torque on a Chevy engine is only 60 ft-lbs. The bolt itself is good for well over 120 ft-lbs

never ever turn a Chevy engine with the nose crank. it strips the threads out of the crank requiring a new crank

and yes, you can strip the tapped threads with a 3/8" ratchet. did it once myself, repaired many engines because of shadetree mechanics trying to turn a motor over by the crank bolt

always use a crank socket, 2 bolts thru the 3-bolt pattern on the damper, or a prybar from the flywheel teeth.

 

[Prophammer]

never ever turn a Chevy engine with the nose crank. it strips the threads

I didn't mean pull on the crank bolt until it snaps off or strips the threads - "feel for it" pull a little then back off - pull a little more then back again - not full force in one direction all at once -

 

[Bondo]

I didn't mean pull on the crank bolt until it snaps off or strips the threads - "feel for it" pull a little then back off - pull a little more then back again - not full force in one direction all at once -

Ayuh,..... Yerself, like many of us, probably has a calibrated elbow,....

But,..... Many,many posters here on iboats, Don't,....

While I may have turned a motor with that bolt, it's still generally, a No-no,....

 

[Prophammer]

Ayuh,..... Yerself, like many of us, probably has a calibrated elbow,....

Rest assured my elbow goes "click" when I hit the right torque

 

[Scott Danforth]

I didn't mean pull on the crank bolt until it snaps off or strips the threads - "feel for it" pull a little then back off - pull a little more then back again - not full force in one direction all at once -

the issue is that any more than the 60 ft-lbs and you can strip the threads. more torque is required to bolt down the starter than the harmonic damper.

best to not even think about turning a Chevy engine by the crank bolt.

 

[davecalman]

first things first , only if you suspect it may be water ingested seized.

and i say this because trying to crank a seized motor with the starter will damage other stuff.

remove the spark plugs and look for sign of water / rust etc.

attempt yo turn the motor with the bolt on the harmonic balance .
if no go , remove the serpentine belt or drive belt whichever you have .
try again .
if it does not turn chances are water got in.
all is not lost yet , , remove the out drive from the equation and try again .

if it turns over fine you can then start investigating the starter , starter solenoid , wires going to starter etc .

good luck .

Thanks for your reply Stresspoint!
Pretty sure it's the pinion in the starter that might be stuck and not engaging with the flywheel. Going to try to remove it if I can manage to remove the rusted bolts!

 

[kenny nunez]

There is rust on the armature shaft preventing the gear from moving to the flywheel. You might be able to clean the rust off once the starter is off. The starter is probably good and should work.

 

[stresspoint]

build a bridge >>>> i am in no way talking using a 4 foot breaker bar on the front bolt and swinging on it to free up a rusted motor , "" please read the posted before giving assumed advice ( being carefully not to get banned again by saying the wrong thing) " >>> remove the plugs to test if the motor is free , not been water ingested seized only.,
seriously, its not going to break that bolt or a fine thread with so little torque , it will be obvious the motor is free. using a 1/2 drive standard length ratchet yo determine how to move on ( common sense) .

OP , be gentle on those starter bolts , the position they are in can make them very hard to get heat torch (waiting for comments from xpurts) onto if they have rust or seized , "from memory on the 3.0 " don't quote me on this , i think the threads in the engine block are open from the top , you can soak some penetrant to help free them up.
keep in mind if you snap one its motor out to get the remainder out .

 

[QBhoy]

Hit the starter a dunt with a suitable object. Your bendix isn’t throwing out. Bridge it out if not.