[OMNI]

hello! I have a significant amount of valvetrain noise after doing the head gaskets on a 93 3vzfe. I suspect the non english speaking people at the machine shop mixed up my lifter shims and maybe even other things. I went in back in to check cam bearing clearance and valve clearance. the cam bearings look slightly polished in areas and I can see lines, I dont expect them to be new looking as parts do wear over time. the intake valves clearance is still in spec while all exhaust valves are out of spec.

haynes stupid manual didn't mention checking bearing clearance during installation and I just did it using plastigauge with the cams still installed. I removed one cam bearing cap at a time and checked clearance. I know this is supposed to be done with the lifters removed but I dont want to go in that far and remove the cams altogether. is there a problem with this? I also notice that I have to exceed the 144inch pound torque spec for the cam bearing cap to get the bearing clearance within spec, instead of torqueing to 12ft pounds I'm torqueing them to 16ft. should I be doing this? the vehicle has under 100k miles. I have a feeling that I should leave this shit alone and just use thicker oil as I still use 10-30. I'm pretty confused at the moment. the headgaskets were done about a year ago and the car ran good but recently has become noisy and a little hard to start. about a good 4 seconds of cranking. I dunno man. any advice is appreciated. thanks for reading my book.

 

[Axel Kain]

strange, but i recently got a bit of what i think is valve train noise in my 92 3vz-fe. i got my Y-pipe replaced, but i tried to do it myself, and got the front disconnected, but not the back, and i think having it like this, and driving 30min to the muffler shop may have warped an exhaust valve possibly...hope not!!! i need to change my valve cover gaskets any way, so ill check what i can check when i do that...^ strange for you tho...id take it to a diff. machiene shop, see if they would check the work and possibly re-machiene anything easy to fix.

 

[73sport]

Not a valid measurement....

Here are my thoughts on what you wrote:
You would not hear noise from the cam bearings if they were too loose. Maybe a loss in oil pressure but not much else.

Measuring the bearings while the valve springs are in will not provide an accurate measurement. If you really want to know pull it apart. Or pull it down completely and mic the cam and mic the bearing journals. Subtract the difference. Once again, I doubt that is an issue unless the engine was neglected for year and never had the oil changed every 3000 miles.

As for torquing the caps beyond spec, bad isea, you can pull threads, stretch bolts, distort the caps, ect..... That being said, once you have don it and run it that way. The damage is done. The good news, 48" pounds (4Lbs is not a lot), so it's prob OK.

Work on isolating the noise and adjusting the valves per procedure. Running thicker oil is not a solution. basically recheck ALL the valves lash and adjust as needed. Look for heavy concentrations of wear (shinny spots) where things are touching that shouldn't touch....

Good Luck, keep us posted.

/ra

 

[OMNI]

well to remove the valve springs I have to pull the head. I think I could do it by removing the lifters and then checking cam clearance. there are some shiny spots on the bearing caps. I figured if I over or undertorqued the cams, that would effect contact with the lifters and throw off that clearance. I just did the right bank today so the car hasn't been driven yet. I checked the exhaust cam on the right bank one cap at a time and they were all at .003 and the spec is .0014 to .0028 I think, the book is outside and thats off the top of my head. so if that reading is true then I need to "replace the camshaft and or head" what the manual says. weird how they outlined the procedure for checking this during installation for the 4 cyl but not the 6cyl. so you think I should pull the whole camshaft out and pull the lifters as well, then check bearing clearance? this would give me a chance to mike the valve shims as well.
ah, so I guess I'm pulling the belts off again. I thought that if I checked the cam bearing clearance one at a time I would get a decently accurate reading seeing as the other caps were torqued down. I have become an expert at pulling this motor apart already, just not a expert in putting it together right. it still runs but I feel dis-satisfied with a job not done 100%. this is probably gonna get me in more trouble. I'm not going to another machine shop ever again, I would rather buy a valve spring compressor and change valve seals myself. half ass mofos charged me and then goobered up my shit. then again, I should have checked all this shit before I started her up.

 

[OMNI]

anybody, input, advice, right wrong? left right? up down?

 

[OMNI]

thanks.

 

[OMNI]

thanks again. the teardown is in effect. I will have to figure this out myself.

 

[Cyorke]

SOrry jsut now found your thread.

FIrst thing you should be torqueing to whatever the manufacturer states.

Second you should always check cam clearance with the rest of the valve train removed. The springs for the valves are pretty stiff and can exert enough pressure on the camshaft to throw off your readings. Obviously this is also done with the timing belt removed since it can exert pressure also. If you have pulled the shim buckets and all then you ahve probably pulled the belt since you can get the shims out without removing the cam and the bel has to ome off before the cam can.

If the engine has been well maintained more than liley you are not going to ahve an yproblems with the cam clearances. I dont think I ever plasigaged one when I was repairing after blown headgaskets. I jsut put it back together and torqued it all down.

please psot more when you get it torn down and let us know waht you find.

 

[73sport]

Yo! You Ever get this fixed to Your satisfaction?

OMNI,
So what happened to your Head? Did you get it quiet?

/ra