Rattle and grinding sound
 

I own a 1999 Chevy S blazer with 177,00 miles on it. Shortly after I purchased this I noticed a rattle that sounded like a nut bouncing in the bottom of a turning barrel. tumbling and banging occasionally. I thought it was probably the flywheel due to the sound location. It always sounds like it is coming from the passenger side, transmission area. Well of course the sound is now constant. My Blazer is a 4x4, so with this the diagnosis for me is very difficult due to the configuration of the drive line and with no bell housing cover to remove to check for broken teeth or a cracked flex plate I'm at the mercy of taking it to the shop I fear. But of course if there is any other thing that you might think it could be then please let me know.

there should be a small inspection plate you can remove and shoot a light up into to get a basic view of your fly wheel. (the shiney guy in the pic)
https://blazerforum.com/forum/pictur...pictureid=7002
you could start there....

I had a similar rattle that got worse over time, and was more noticable early in acceleration, but not so much so at speed. I had cross-threaded flywheel nuts that had backed off a bit and were allowing my flex plate to wobble and bang a bit. :icon_shrug:

Is that inspection hole large enough for him to get a magnetic pick-up tool in there? Maybe one of the flywheel bolts came out.

Rattle and grinding sound
 

I was also wondering if that hole would allow me to see if there is a crack in the plate? I would think no though. How would I rotate the flywheel with out bunping the starter?

Put a 5/8" socket/wrench of the Harmonic Balancer nut and manually rotate the engine clockwise a little at a time as you inspect.

Thanks for the advice and help.

You could stick a pick up tool in there, but the inspection hole wont be big enough to check the whole plate (with out a snake cam or a mechanics mirror, light and a lot of patience)

As for manual fly wheel action, you can also wedge a pry bar in there and turn the wheel. thats what i did when i forced water into the engine to see if i had ruined anything (bonus! it showed me that i had!)

Why not turn the harmonic balancer with a wrench?

sparky672: because until recently i had no idea wtf a 'harmonica ballister' was, and i could id a flex plate because at the time to only other thing i had ruined on a car was that plate :D

*you'd be surprised at how ugly a nova sounds slamming down on a parking divider. :icon_eek: