Stuck Screwdriver

[towboater1]

Was trying to find top dead center on my lil 140 Mercrusier and was doing this by myself.1st mistake,anyway I put a long screwdriver in the #1 cylinder with the thought as the engine rotated by bumping the key the piston would slowly push the screwdriver up.Well as my luck would have it the screwdriver seems to be wedged between the top of the piston and the cylinder wall at the top I'm guessing.Any ideas on how to reverse the engine?I'v tried putting it in forward position with the throttle and work the wheel in reverse,but no luck.I even pulled all the plugs to help release the compression.Any ideas other then pulling the top end down may help.

 

[Don S]

Re: Stuck Screwdriver

Was trying to find top dead center on my lil 140 Mercrusier and was doing this by myself.1st mistake,anyway I put a long screwdriver in the #1 cylinder with the thought as the engine rotated by bumping the key the piston would slowly push the screwdriver up.Well as my luck would have it the screwdriver seems to be wedged between the top of the piston and the cylinder wall at the top I'm guessing.Any ideas on how to reverse the engine?I'v tried putting it in forward position with the throttle and work the wheel in reverse,but no luck.I even pulled all the plugs to help release the compression.Any ideas other then pulling the top end down may help.

Pull the head, you need to inspect things.

 

[Bt Doctur]

Re: Stuck Screwdriver

remove the drive and use a T bar with an old shaft welded to it
using the 4 bolts on the waterpump pully,wedge a screwdriver between 2 bolts and pull on the fan belt,to turn the cranki backwards.

 

[Don S]

Re: Stuck Screwdriver

remove the drive and use a T bar with an old shaft welded to it
using the 4 bolts on the waterpump pully,wedge a screwdriver between 2 bolts and pull on the fan belt,to turn the cranki backwards.

That might get the screwdriver out but what damage did that screwdriver cause in the process of getting stuck.

 

[towboater1]

Re: Stuck Screwdriver

That's what I thought I was going to hear....I can't figure out how the thing got jammed,I mean the piston don't drop far enough down the cylinder foe a screwdriver to fall between the piston and the bottom of the head?

 

[towboater1]

Re: Stuck Screwdriver

I know....my timing was out and I thought I was going to do this Quick timing change....LOL Boat...Break Out Another Thousand....

 

[Don S]

Re: Stuck Screwdriver

When you use a screwdriver to check when the piston is up, you turn the engine by hand, not with the starter.

Removing the spark plugs, and making sure the alternator belt is tight, and you can easily turn the engine by putting a wrench on the alternator.

 

[Bt Doctur]

Re: Stuck Screwdriver

Depends on how gentle he was with the starter,with any kind of good spin, the head has to come off for inspection.
Best case, nothing happened, worst case it punctured the cylinder wall.

 

[rickryder]

Re: Stuck Screwdriver

remove the drive and use a T bar with an old shaft welded to it
using the 4 bolts on the waterpump pully,wedge a screwdriver between 2 bolts and pull on the fan belt,to turn the cranki backwards.

You could use the 4 bolt and screwdriver as stated but also have someone with a socket and breaker bar on the crank and see if you can back the motor up and remove the screwdriver from the plug hole.....

You do need to see if you have damaged anything inside and also look at the plug threads..... To get a look without pulling the head you could use a bore a scope..... of course to be absolutly sure everything is perfect the head must be removed like Don S said above...

Good luck!

 

[Bondo]

Re: Stuck Screwdriver

When you use a screwdriver to check when the piston is up, you turn the engine by hand, not with the starter.

Removing the spark plugs, and making sure the alternator belt is tight, and you can easily turn the engine by putting a wrench on the alternator.

Ayuh,.... 'n use something less than a screwdriver,... Like a plastic straw maybe....

I don't see a Nice outcome....

Hopefully the battery is near dead, 'n the starter was draggin'.....
A compression test might give ya a hint of the damage...