Hydro-lock when stationery?
Melting Slicks
Joined: Oct 2007
Posts: 2,383
Likes: 13
From: Kinston North Carolina
This is a wild #$$ guess, but very possible. Something got caught between the teeth of the starter bendix gear, and the teeth of the flywheel. That would be enough pressure to break to break off any starter mount.
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,074
From: Lansing MI
it didnt hydro lock
i have experienced many hydro locked engines. This is not what happens.
This does happen if a starter bolt is loose.
The fact that only one bolt hole through the nose cone of the starter and one hole in the block broke is pretty much all the evidence you need. How could one break off like that if the other one is nice and tight ? It cant.
The only other time ive ever seem damage like that has not been on a corvette and was only to the starter. If your crank sensor is screwed up or on older engines you cross some plug wires or do somthing to cause a misfire and the engine ries to rotate backwards it can damage the starter.
This does happen if a starter bolt is loose.
The fact that only one bolt hole through the nose cone of the starter and one hole in the block broke is pretty much all the evidence you need. How could one break off like that if the other one is nice and tight ? It cant.
The only other time ive ever seem damage like that has not been on a corvette and was only to the starter. If your crank sensor is screwed up or on older engines you cross some plug wires or do somthing to cause a misfire and the engine ries to rotate backwards it can damage the starter.
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
Thanks for the part number - I will get a replacement on order
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
i have experienced many hydro locked engines. This is not what happens.
This does happen if a starter bolt is loose.
The fact that only one bolt hole through the nose cone of the starter and one hole in the block broke is pretty much all the evidence you need. How could one break off like that if the other one is nice and tight ? It cant.
The only other time ive ever seem damage like that has not been on a corvette and was only to the starter. If your crank sensor is screwed up or on older engines you cross some plug wires or do somthing to cause a misfire and the engine ries to rotate backwards it can damage the starter.
This does happen if a starter bolt is loose.
The fact that only one bolt hole through the nose cone of the starter and one hole in the block broke is pretty much all the evidence you need. How could one break off like that if the other one is nice and tight ? It cant.
The only other time ive ever seem damage like that has not been on a corvette and was only to the starter. If your crank sensor is screwed up or on older engines you cross some plug wires or do somthing to cause a misfire and the engine ries to rotate backwards it can damage the starter.
Where is the crank sensor located? Is it inside the engine?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The crank sensor is right in your picture with the circle!!! 
It right above the starter. It is the sensor with green, yellow and black wires
That black thing thats broken is the bell housing cover. It is easily replaced . Order it from Gene Cullley.
Unless the insurance company wants that block back,,,,I would KEEP IT. That can be repaired!!!! There was some one else on here that had that damage and had it welded!!
BC
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
The crank sensor is right in your picture with the circle!!! It right above the starter. It is the sensor with green, yellow and black wires
That black thing thats broken is the bell housing cover. It is easily replaced . Order it from Gene Cullley.
Unless the insurance company wants that block back,,,,I would KEEP IT. That can be repaired!!!! There was some one else on here that had that damage and had it welded!!
BC
Bill, this is not an "insurance" swap, but rather being replaced under my GMPP Extended Warranty - so GM takes to core. The dealership did have a couple welders look at this first, but due to the break location and size of the broken off piece, nobody wanted the responsibility of standing behind the repair - so the GMPP adjuster approved a new replacement engine.
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
They are getting ready to remove the Torque Tube today at the dealership. We noticed that when we removed the rear rubber plug on the Torque Tube housing, that it looks like the back of the metal plate on the Torque Tube is somewhat chewed up around the perimeter. They asked me if I heard anything "rattling around" the last time I drove the car (which I didn't). It "looks" like a bolt head or piece of metal may have come loose inside and that MAY be what caused the starter to fail (if it got trapped between the starter gear and the flywheel)?
We could not see or feel anything through the opening, but we may find the culprit when we get the tube off?
The Dealership did remove the Torque Tube from the engine about a year ago - so maybe they did not get something put back tight?
We could not see or feel anything through the opening, but we may find the culprit when we get the tube off?
The Dealership did remove the Torque Tube from the engine about a year ago - so maybe they did not get something put back tight?
Melting Slicks
Joined: Aug 2006
Posts: 2,167
Likes: 11
From: Powell TN
Cruise-In VIII Veteran
They are getting ready to remove the Torque Tube today at the dealership. We noticed that when we removed the rear rubber plug on the Torque Tube housing, that it looks like the back of the metal plate on the Torque Tube is somewhat chewed up around the perimeter. They asked me if I heard anything "rattling around" the last time I drove the car (which I didn't). It "looks" like a bolt head or piece of metal may have come loose inside and that MAY be what caused the starter to fail (if it got trapped between the starter gear and the flywheel)?
We could not see or feel anything through the opening, but we may find the culprit when we get the tube off?
The Dealership did remove the Torque Tube from the engine about a year ago - so maybe they did not get something put back tight?
We could not see or feel anything through the opening, but we may find the culprit when we get the tube off?
The Dealership did remove the Torque Tube from the engine about a year ago - so maybe they did not get something put back tight?
There is a clamp in there with a bolt in it. It holds the splined part of the flywheel to the input of the propeller shaft. Did that bolt come out? It is supposed to be torqued to 92 ft lbs. but, according to the service manual, you are supposed to drive it for at least 10 minutes and then let it cool overnight before torquing the bolt. Maybe they forgot?
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Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
You mean the front (oval shaped) rubber plug? The rear plug is where the torque converter is.
There is a clamp in there with a bolt in it. It holds the splined part of the flywheel to the input of the propeller shaft. Did that bolt come out? It is supposed to be torqued to 92 ft lbs. but, according to the service manual, you are supposed to drive it for at least 10 minutes and then let it cool overnight before torquing the bolt. Maybe they forgot?
There is a clamp in there with a bolt in it. It holds the splined part of the flywheel to the input of the propeller shaft. Did that bolt come out? It is supposed to be torqued to 92 ft lbs. but, according to the service manual, you are supposed to drive it for at least 10 minutes and then let it cool overnight before torquing the bolt. Maybe they forgot?
Melting Slicks
Joined: Aug 2006
Posts: 2,167
Likes: 11
From: Powell TN
Cruise-In VIII Veteran
The clamp is basically a square block of metal about 2 1/2" x 2 1/2" and 3/4" wide (this is off the top of my head). The hole in the center fits on the grooved area of the propeller shaft hub. There is a small slit on one side of the clamp and the bolt goes into the clamp on one side of the slit and tightens to the the threads on the other side of the slit.
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
[QUOTE=2000C-5;1567682173]Oh yeah, it can definitely be seen. It is straight up above the access hole. The clamp itself should still be there, as it cannot come off, but the bolt may have come out and caused the problems you have.
The clamp is basically a square block of metal about 2 1/2" x 2 1/2" and 3/4" wide (this is off the top of my head). The hole in the center fits on the grooved area of the propeller shaft hub. There is a small slit on one side of the clamp and the bolt goes into the clamp on one side of the slit and tightens to the the threads on the other side of the slit.
Great... thanks for the diagram. They still have not removed the TT (or anything for that matter) after having the car over two weeks so far (was supposed to be completed by today). I got under the car today and it looks like the clip and bolt are still connected - so must be something else. Just have to wait until they get it off!
The clamp is basically a square block of metal about 2 1/2" x 2 1/2" and 3/4" wide (this is off the top of my head). The hole in the center fits on the grooved area of the propeller shaft hub. There is a small slit on one side of the clamp and the bolt goes into the clamp on one side of the slit and tightens to the the threads on the other side of the slit.
Great... thanks for the diagram. They still have not removed the TT (or anything for that matter) after having the car over two weeks so far (was supposed to be completed by today). I got under the car today and it looks like the clip and bolt are still connected - so must be something else. Just have to wait until they get it off!
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
Well we finally got the old engine out at the dealership and looked real close to see if there was anything loose that might have jammed between the flywheel and the starter gear teeth, but found no cause. Anyway, here is a photo of the break in the block with the engine removed...
