Flywheel not turning when Hoe is pushed in gear

[Bamba]

I thought I had a starter or solenoid problem when my Tahoe wouldn't start.
I got a tow home and when I took the starter off, I noticed that about 4-5 teeth were missing from the flywheel. I tested the starter and the solenoid kicked out and turned just like it should.
When I initially had the (No Start) problem, I had pushed the vehicle a couple feet or so while it was in gear, thinking that maybe I could get to a spot on the flywheel with good teeth. I got the same grinding sound and the engine wasn't turning.
I marked the flywheel at the location where the teeth were missing with a red marker, then put the vehicle in gear and pushed it a good 2-3 ft.. Checked the flywheel and ... The flywheel DIDN'T MOVE??? I did the same thing in Reverse.. Same result??

What could be the problem?

There has never been any hard start problems before this incident... EXCEPT... That same day I heard the same grinding noise when starting but I was able to just try it again and it started with no problem.

Thanks in advance for your suggestions. 1998 Tahoe with a 5.7 4WD engine.

P.S... I've always had a problem with the Tahoe not going into 4WD but that doesn't seem to have anything to do with this??? Right??

 

[retorq]

What's the problem?? You have an automatic transmission. The convertor and flywheel aren't going to move if you push the truck ... that's just how they work.

You have no choice but to pull the flywheel ... you will need to drop the driveshafts, unbolt the tranny and move it back about 6-12 inches ... if you have the room to do so. The last time I killed a flywheel (in my Camaro) it was easier to drop the tranny then it was to wrestle with everything in the air.

 

[SunlitComet]

I don't recall the 1998 having a manual tranny so I will assume that it is auto 4l60e. If so you will not be able to move the fly wheel by putting into gear. Thay don't work that way. Sorry, but your tranny will have to come out and your flywheel replaced. When your done if you can, have your computer checked for a stored p0338 code Therew was a tech bulletin that had this as a symptom. It may just be a one time thing but if it is related to the code more expensive damage could result later on. Here is a brief:

Condition:
Some customers may comment on one or more of the following conditions:

^ Backfire during crank/start
^ "Kickback" during crank/start
^ "No" start
^ "Slow" or "hard" start/crank
^ "Grinding" or unusual noises during crank/start
^ Cracked or broken engine block at the starter boss
^ Broken starter drive housing
^ Broken starter ring gear on flywheel
^ Any combination of the above

Cause:
A condition may exist that allows the crankshaft position sensor to command up to 50 extra degrees of spark advance during engine cranking only. This in turn exposes the engine to higher than normal cylinder pressures which may result in an inoperative condition to the starter drive housing, the engine flywheel starter ring gear, or the engine block at the outside edge of the starter boss.

---------- Post added at 01:16 PM ---------- Previous post was at 01:12 PM ----------

the 4x4 is a seperate issue.

 

[Bamba]

Thanks for your replies guys

The thought of replacing the flywheel just because it's missing 4-5 teeth isn't comforting. Eventually I'm sure I'll have to do it but now is the worst time for me to undertake a job like that. This weekend would be much better.

Isn't it possible to turn the flywheel manually by turning the craknkshaft bolt clockwise with a large breaker bar? If it is... isn't that the big bolt near the harmonic balancer?

I don't know why I thought an automatic Tranny would turn while being pushed in gear.... Learn something new everyday.

 

[SunlitComet]

Just let it go already. Even if you turned it enough so the starter would engage within one revolution while cranking you are going to do more damage as soon as the mising teeth come back around.

 

[Bamba]

Yea Sunlitcomet, you have a point there.

I wonder what would have caused the starter to chew up the flywheel like that in the 1st place?
My logic would say that the teeth on the solenoid should be made of a softer metal than the teeth on the flywheel to prevent failures like this.
It's a lot easier (and cheaper) to replace a solenoid than it is to replace a flywheel.

I think I'll have that starter checked (under load) Before I use it with my new flywheel.

 

[retorq]

Having your starter checked is a GREAT idea. When I replaced my flywheel I had the starter looked at locally and the gear was no good. Also make sure you are using REAL starter bolts with the knurled ends. If you aren't there is a very good chance this will happen again and again ... normal bolts aren't goign to keep the starter from jumping around.

Also I wouldn't suggest turning the engine with the bolt on the front. I've stripped the threads out of the snout of the crank that way ... they make flywheel tools for situations like this ...

 

[95TwinTT]

I don't know why I thought an automatic Tranny would turn while being pushed in gear.... Learn something new everyday.

The early Hydromatic's were able to start the engine by pushing the vehicle. They gave up the "rear pump" in 1957-1958. You must have heard about the pushing part from an old timer.............

 

[Bamba]

Also make sure you are using REAL starter bolts with the knurled ends.

Also I wouldn't suggest turning the engine with the bolt on the front. I've stripped the threads out of the snout of the crank that way ... they make flywheel tools for situations like this ...

Yes I "do" have the bolts with the knurled ends... I was wondering what that was all about... Thanks for bringing it up

What are the "flywheel tools" for situations like this?? One mechanic suggested that I turn the flywheel with a "big screwdriver" inserted between the teeth?? I thought that was "worse" than turning it with a big breaker bar.

---------- Post added at 09:07 PM ---------- Previous post was at 09:00 PM ----------

The early Hydromatic's were able to start the engine by pushing the vehicle. They gave up the "rear pump" in 1957-1958. You must have heard about the pushing part from an old timer.............

Hahahaha Transmissions never have been my strong suit Thanks for making me feel like I'm not crazy.... Half of what I know came from "Old Timers" .... lol

 

[SunlitComet]

the is a tool.