Breaking In- Sounding raspy.

[oneblueyedog]

I'm following the break in routine. I have about 250 miles on the car. Iv'e done 2 oil changes.

It's sounding raspy in that it has valve train noise. It's like it needs a valve adjustment, clicks like a VW Beetle. Not really that bad but noticeable when hot.

The accelleration seems like it's not pulling as hard. But I might be getting used to the car again. I also put the air pump back on.

I assume since the rockers (New) are wearing into the Cams(regrinds) that the noise is normal and the reason why we readjust the rockers /valves at 1k.

It's still is a kick to drive. Should I readjust now? Wait until 1K? It's bugging me.

I'm still going up to 5k through the gears and deccelerating through the engine.

I assume the valve adjust will help a lot since it's critical with timing.

What is happening to timing when valves loosen?

Lee78sc

[jgparker]

It will cost you close to nothing to adjust the valves, and you might find the problem, and save youself some serious grief. I found a broken head stud when I did my valve adjust at 300 miles due to a raspy exhaust note.

Good luck,

JP

[Wayne 962]

Yup, a valve adjust can't hurt. I would be wary of the "butt dyno" - I know that mine is notoriously inaccurate.

You may also be super-sensitive to the valve train noise. Compare it to another 911...

-Wayne

[garibaldi]

Just a little bit of advice. If something doesnt sound right, then it probably isnt. If the work was done correctly, and everything was in order, then there really is no reason why you should have any type of abnormal noise after a rebuild.

[oneblueyedog]

Thanks for the replies!

I took a break this weekend and did some skiing. Got back last night and the car didn't miss a beat. Parked at idle after the drive back from the airport, just slight clicking. I must have a valve a tad loose.

I drove it to work this morning. An M3 was in front of me at a light and I wanted to see if I could keep up with him. Oh yes indeed. I don't know if he was getting on it but I was staying wth him a 5500 in each gear as we entered the tollway.

Got to the parking garage and just that slight click from the valves. I'm concluding that a I misadjusted a valve. But there is one if. I did not replace the rocker shafts with the rocker arms.

I assume worn shafts would make for adjustment trouble? I installed the old ones with the wear surfaces (I noticed only one-shiny but no galling or discoloration) opposite from the way the cam would put force on the rocker. I also installed this shaft on #6 for a slightly easier replacement.

In hindsight, I should have replaced them all. The doubt will always be there. I won't know for sure until I do the 1000k valve adjust. Hope it goes away.

Someday, I'd like to experience the drag of a feeler gauge of a properly adjusted 911 SC valve set by a master Porsche Mechanic.

Christian, if I ever get to Madison, can I schedule an appointment?

Thanks,
Lee78SC

[Superman]

I also did not replace the rocker shafts. Could have. No regrets.

When you adjust valves...soon....also put a torque wrench onto the head stud barrel nuts. See if they're still torqued exactly right. Probably not.