newbie wants to know when you need a vavle adjustment
 

is there a way to tell when you need a valve adjustment. miles??? timeframe??? car only has 30,000 miles, but last service before i got it running (new plugs, oil, fuel filter, etc.) was '99.

Miles - that's the only thing you can go with. Noise not so much, as the gap actually gets smaller with miles. Do you have the mileage of the last service?

If it were my car, I'd just go check / adjust them. Takes only an evening and a couple of beers.

George

Valve gap get smaller with miles???
 

"Noise not so much, as the gap actually gets smaller with miles."


And how does that exactly happen??

I think he meant "bigger".

Physics ? I do not know how but it has been my experience as well that the gaps tighten.

It does not make sense, the wear of rocker metal on cam metal and heat cycles should result in a larger gap.

My experience is limited to about 10 Valve adjustments on a single engine. I hope someone with more experience will share.

Shane

I actually meant that the gap tightens:

The valve seats and valves wear. This means the valve sinks into the head, which in return moves the valve stem closer to the rocker arm. The wear on the rocker arm, valve stem and cam is significantly less than the wear of the valve and seat. Also, this wear is mostly happening on the exhaust valves, due to the much higher temperatures.

If you do not adjust your valves for a long time, the exhaust valves will not close any more with full force, because they will wear to the point where the gap is nil. Then the exhaust valve gets hot because it doesn't cool right any more in the valve seat and you will burn them up.

So, get a couple of beers cold, get on your back and at least check the exhaust valves. In addition to the valve check this will also give you a check on the head studs - those can break any time - regardless of mileage. :D

Hope this helps,

George

According to "prevailing" wisdom, for "normal" usage, every 15K miles.

Don't bank on finishing it in one night on your first time.

Take your time as it can be frustrating - you will change the gap when you tighten the adjusting nuts so multiple passes are required for the uninitiated.

Look at youtube videos of how this tool is used. It's pretty cool. http://forums.pelicanparts.com/porsche-911-technical-forum/464289-tried-my-new-vas-911-valve-adjust-screwdriver-36-degree-pointer.html

My first took me about seven hours with some other stuff like changing the fan belt, and general putzing about. The one this spring took about nine hours, but I did pretty much everything: valve adjustment, oil change, fuel filter, air filter, spark plugs and cap and rotor. I also took some extra time playing and experimenting with the VAS 911 tool, and the back side method.

With that in mind, I imagine every spring will call for the same thing with an oil change or two in the middle. I figure that after the 12000 miles I put on this past year, it should be rewarded with a valve adjustment and other loving touches. If it's only half a weekend a year and a couple hundred bucks, what's it gonna hurt?

I sure don't miss those valve adjustments. ;)

You get more lift, generally, after re-adjustment, so there you go 5 hp seat of the pants at any rate!

George

every 15K miles, religiously.

For a first timer, I would recommend setting aside a weekend. Not that it takes that long, but I would do the following on the first day: drain oil, remove a/c compressor, heater blower motor, and any other things that will get in the way. Remove intake and exhaust valve covers. Clean everything up for reinstall.

On the second day, I would adjust the valves, taking care to make sure the gaps are correct...there are lots of threads on this subject. After adjusting the valves, put everything back together, start the motor and enjoy the fruits of your labor...and be smug in the knowledge you saved yourself $200-$300 in the process.

On the second

Most people time it to coincide with an oil change. Having said that, it works out to about every other oil change, or around 15,000 miles +/-.

If you have a lot of valve noise, then do it early. If you have a loss of power or a smog test coming up, do it early.

i dont need one yet, but i will let you know.