I was driving last week and statred to here chattering from the valve cover on the passenger side. I noticed that the oil was very low and quickly changed it along with some Lucas addative. the problem went away, but you can her some very small chattering after a while of driving. Its not a bothersome sound, but Im wondering did I cause any damage and what is going on with it chattering? Can this problem be simply fixed or am I looking at future distruction? is this also from old wear and tear. The car has 139000 miles on it.

 

more then likely the rockers are slightly out of adjustment from wear. Could be too thick of oil used.

If its not overly loud, dont worry about it.

 

Im running castrol 10-40. Can i simply adjust them and put back on the covers? Is this a normal sound from high mileage engines?

 

somewhat normal for that milage.

As easy as it sounds. you have to pull off the upper intake. And then follow an order/pattern of tighting. Can be done if you have some mechanical skills and half a day to do it.

10/40 may be ok for cali temps. I belive stock specs on these engines was 10/30 though

 

stock is 5/30 for these but 10/40 should be fine and not cause problems

normal rocker wear compounded by runnin without oil for a while probably

 

Should i be worried about this adjustment? I think I have enogh skill to pull it off, And if I follow the tightening sequence in the haynes manuel without replacing parts, should i be fine or are there other ajustments that have to be made on the upper end of the engine? also if I do this will there be a difference in the performance of the engine without new parts?

 

I am not sure the haynes was correct? Id have to look at the haynes to my gm book to make sure.

You would need to replace every gasket. But other then that, no true phyiscal parts would need to be replaced.

Since its not a loud knock, or all of the rockers from description. No, you would see little to no performance gain. More then likely all are just a hair loose, with one being a little more then the others.

 

Thanks dude? one last ? what was making the sound louder the first time?

 

lack of oil, and possibly to thick of oil. Then add this into the mix.

Snowball effect.

Just keep an eye on it, if it starts to get worse, then its time to take the top apart and inspect.