Valve loose again???

[nene]

I adjusted my valves (using the Back-Side method) to my 3.2 about 200 miles ago and made sure they were nice and tight and to spec. I recently started feeling the car shaking a bit when at idle, and also some excessive noise. I opened up the passenger side valve covers and starting taking the valve-gap measurements, and to my surprise, they were all loose!! WTH!!

Using both of the required Go No-Go gauges, I was able to slide both of them, one at a time with no resistance at all!! What is going on here??

Note- according to the PO, the engine had been "overhauled". So here is my question, when a engine has been "overhauled" or refreshed, would this cause
"general" items to loosen up? I did have one loose head-stud last time I adjusted the valves, so it makes me wonder??

Thanx,

Serge

[pete3799]

Don't know......but adjust them again.
.0025 go .003 no go....... works for me.
Pelican Technical Article: 911 Valve Adjustment - The Backside Method

[snbush67]

Did you adjust you valves with the engine stone cold?

And have your loose, subsequent measurements been taken with the engine stone cold?

I haven't measured my valves when warm, but others report that when warm the valves loosen. So that may be your issue.

[brighton911]

Were they quiet after the first setting? If so, my thoughts are: perhaps the settings changed because the lock nuts were not tight enough or something is wearing in the valve train - cam lobe or rocker face. Rocker shafts moving could be an issue too. Good luck.

[nene]

Thanx for the input - First, I am familiar with the process and yes, I adjusted the valves in the "Cold-Stone" state. It sounds better and they weren't too loud, but I wanted to just check them. I really don't think the Cam Lobes or Rockers have worn that much in 200-300 miles.

Any other thoughts??

Sergio