I just finished replacing my opti, old one was making a grinding noise internally but seemed to work fine..

When I installed the new one, before installing any of the mounting bolts, should the 3 opti mounting surfaces be touching the timing cover at all?
When I installed it, all of the mounting plate surfaces were about 1/8" from touching the timing cover mounting spot, then the bolts when installed pulled the opti the rest of the way down that 1/8".
The opti would not go on any further.
The pin was lined up otherwise I would have had alot more than 1/8".

It started up just fine and sounded like the grinding noise was gone until it started getting up to op temp then you could begin to hear it faintly and it is coming from the opti as I put a stephescope to the opti front as the car was running and the noise definitlely picked up from intial startup.
Don't want to run it anymore if its going to cause it to have the same problem or is this normal?

The old opti does have something definitely rubbing on the inside when turning the shaft by hand..haven'ttaken it apart yet to see what it is..

 

All the optis Ive ever installed mounted flush with the timing cover. never needed to haev the tabs tightned down.

 

Did you check the dowel pin length on the cam? Could be too long, which would explain why it wouldn't mount flush with the cover.

 

QUOTE=MEAN LT1;4220255]All the optis Ive ever installed mounted flush with the timing cover. never needed to haev the tabs tightned down.[/QUOTE]

I agree with mean LT1. Are you sure you have the dowl pin in the right part of the clover leaf?

http://www.golenengineservice.com/html/gmhtp_3a.html[

 

Yes, the dow pin lined up with the square hole between the clover leafs. I checked the length of the pin to make sure it did not need grinding off and it was about 1/16" shorter than the slot it fits in was deep.
The old one when I removed it was not flush at the mounting hole/bolts either... I'm guessing thats the cause of my noise now...
Not sure what to do from here short of tearing the motor down to see why the cam is not fitting in further...maybe take some thin puddy and fplace it in to see just whats touching to keep it from going down all the way..

 

I could have swore my cam dowel pin was too long. It would only get to about an 1/8 inch from the timing cover, but after a couple of minutes of jiggling I finessed it in with an audible click tight against the timing cover. Maybe the opti and cam seals are giving it slight resistance.

 

"I used the bolts to pull the opti flush" is a common phrase in failed-opti threads. You have something out of spec with the timing set/cam/etc.

 

Thanks all who replied. Guess I'll have to tear it back down in a few weeks again to figure this out. Its ran a few thousand miles this way with the old opti, its obviously got something out of whack to make the noise it is but it'll have to wait a week or so before I can do it again...guess I need to order up another opti for the job....

 

Well I tore it down tonight and replaced the opti again, this time it did go flush with the timing cover with a little tap with my palm....but it makes the same noise!!
On the first one I replaced, appearently the pin wasn't quit in the right spot, you could see a little mark where the pin hit, but it appears that when I tightened the bolts and pulled it down it slipped in place..looked like maybe it was just on the very edge.

Any way..same dam noise so maybe it is the timing chain and the noise is just reverberating out the front of the opti since its directly connected to the timing gear.......I'm not going to worry about it anymore, if it tears something up then someone will get a good deal on a vert and I'm getting another turbo Buick, this car has been nothing but a pain after the mods started ...but my LT4 in the truck has been flawless.