First valve adjustment.

[rrnixonjr]

I need some help. Just started my first valve adjustment on my 89, 911. Am going to use to back side method. Took off all valve covers and discovered that number 4 cylinder (ride side rear cylinder) rocker arm shaft appears to have slid partially out of its correct position. The forward part of the shaft is showing its groove and the rear part is forward enough that it is hard to feel, but is still in the housing.

Looks like the camshaft is not damaged, everything looks very clean despite
130,000 miles on the engine. What should I do? Should I loosen up the bolt, center the shaft, tighten things up and go on with the valve adjustment? Or should I remove the shaft and rocker arm and inspect for wear before I go on?
I wonder why this happened in the first place.

Any help for this poor lost soul would be appreciated. Happy Thanksgiving!

[Walter_Middie]

rrnixonjr,

I would suggest centering the shaft and then just keep an eye on it. There are 2 tricks you need to know. If you have Wayne's engine rebuilding book these are described in detail there.

1.) only one side of the shaft bolt should turn to loosen it. One side is the nut that should not turn, and the other side is the end of the bolt that does turn. Make sure you know which is which so you don't damage the cam tower by turning the nuts that lock into the cam tower.

2.) Don't over tighten the shaft bolt when you reinstall it. It could be that whoever rebuilt this engine was too easy on the torque so as to not damage it, then it ended up being too loose. There is a fine line between too loose and too tight.

[rrnixonjr]

Thanks for the reply, I have Wayne's book and will consult it on which side to loosen.

[Scott98]

Originally Posted by Walter_Middie

rrnixonjr,

I would suggest centering the shaft

DON"T CENTER THE SHAFT! The edge of the shaft should be just shy of even on the THINNER flange on your camshaft housing. Remove the rocker shaft bolt and nut completely before moving the shaft. When the bolt is tightened, it expands the shaft. If you try to move it with the bolt in it, you could damage your camshaft housing.

Once you have the shaft in its correct position, insert the bolt and 8mm nut. Hold the nut steady and tighten by turning the 5mm bolt - NOT the nut. You must have a 1/4 drive torque wrench and a special 5mm socket from Hazet to tighten the bolt. There is very little clearance and you will need those tools to access the bolt. The tightening torque is 15Nm (11 ft-lb).

Scott

[Gunter]

Check all the others while you're at it.
Depending on the source, the torque is 11-15 ft-lbs.
Bentley = 11, Wayne = 13.2, Anderson 15.
The 8mm Allen holds the nut while the 5mm Allen tightens the bolt.
Since there is no room for a torque wrench, the short Allen wrenches will have to do.
Get a feel for the right torque by using a calibrated torque wrench.
I think the pinch bolts have a 6mm thread.
Put a 6mm nut in a vice with a 6mm Allen bolt in it.
Set the torque wrench to 12 ft-lbs, use a 5mm Allen socket and tighten the Allen bolt into the nut.
Now use the short Allen wrench and tighten it just a tiny bit more. (To get 13 ft-lb is tighter than you think with short Allen wrenches))
This will give you the feel for the right torque.
Do them all but make sure the shafts are sitting centered as per instructions in Wayne's book or the Bentley.

[Walter_Middie]

DON"T CENTER THE SHAFT!

As Gunter points out, the shaft is centered - on the rocker arm not the camshaft housing. I assumed that if rrnixonjr had the engine rebuild book, he would get the details correct from that.

[rrnixonjr]

Thanks to all for the right procedure, I will follow carefully after I digest this turkey. Hope you all had a fine Thanksgiving!

[rrnixonjr]

By the way, I feel extemely fortunate to have all of your help. Thanks again.

[rrnixonjr]

Extremely.

[Scott98]

[QUOTE=Gunter;3602601]Since there is no room for a torque wrench, the short Allen wrenches will have to do.
QUOTE]

A 1/4 inch drive torque wrench fits perfectly in there with the 5mm Hazet socket.

Scott

[rrnixonjr]

The back side method is not working for me. Too difficult to get fine feeler gauges in place, too finicky for me after four hours of trying. I will now try the normal way.

[Gunter]

[QUOTE=Scott98;3602873]

Originally Posted by Gunter

Since there is no room for a torque wrench, the short Allen wrenches will have to do.
QUOTE]

A 1/4 inch drive torque wrench fits perfectly in there with the 5mm Hazet socket.
Scott

Scott:
Love to see that.
The 1/4" torque wrench would have to have a fairly small head and the socket has to be pretty short.
Can you post a picture of the whole tool? Wrench and socket together.

Please.

[Gunter]

Originally Posted by rrnixonjr

The back side method is not working for me. Too difficult to get fine feeler gauges in place, too finicky for me after four hours of trying. I will now try the normal way.

I tried both methods and feel comfortable with the old way of using the special tool P213b with the small 0.1 mm blade.
Check the tiny screws/nuts on the tool, they can come loose.
I use a short stubby screwdriver and a good box end 13 mm.
Keep the wrench square to the nut so you don't round off the hex when tightening.
An easy way is to just simply back the adjuster off, insert the special 0.1 mm blade, then snug the adjuster onto the blade and tighten the nut.
That way you don't have to "fish" for the blade to get under the elephant foot.

Of course, it helps if there is no AC or CAT in the way.

[livi]

Originally Posted by rrnixonjr

The back side method is not working for me. Too difficult to get fine feeler gauges in place, too finicky for me after four hours of trying. I will now try the normal way.

That is how I felt too the first time I tried that method. Seems very straight forward any many swear by it. I found the factory method much more to my liking. Suited me very well actually.

Good luck!

[wesayso]

Did my first 911 adjustment using the backside method this weekend. It was hard at first, about an hour on the first 2 valves but after I got used to it I started to like this method. I used metric sizes but that doesn't change the concept. The finest blade was hard at times to slide in but usually it would work to slide it in from the side instead of poking in the center of the rockerarm-camshaft opening. I'm sold to this method now. The only hard part was the running around the car (under the car, in engine boot) for each valve.

[rrnixonjr]

Thanks for all the helpful comments. I needed all the support I could get yesterday, ended up spending six or more hours and accomplishing nothing.

Started this morning fresh, with the same poor results. Went back to the tech articles and looked up the factory valve adjustment method. Within two hours had 3 cylinders adjusted. The factory method, while finicky, was much easier to get right, for me at least. I like the precision of starting with cylinder number 1 and moving through the firing sequence every 120 degrees. No guessing. What's interesting is that checking with the backside method, .0025 and .003 no go it was much easier to get right, and much faster. Fortunately too, as it was starting to get grim, my dog wouldn't even get near me. Tomorrow I will finish up and do an oil change.

Now I know why it costs 500 bucks to do, although I would not hesitate to do it myself next time. The second time will definately be easier.

[rrnixonjr]

By the way, I used a regular .004 straight feeler gauge which I had bent about an inch from the tip at a 90 degree angle. Was so sure of myself that I did not buy the special tool so I had to improvise.

It worked great although at one point I lost the gauge for twenty minutes. Bad twenty minutes, dog whining. Found feeler gauge and put yellow zip tip on it.
Great confidence builder is checking with .0025 and .003.

First cylinder was abysmal, bad visibility, touch only, catalytic converter in the way and funny ratcheting screwdriver hitting me in the head every time I dropped it. Not to mention hair in oil left on floor. Dog found new owner. After that things looked up and I started feeling somewhat competent again.

Actually looking forward to tomorrow, although my body may not be after getting up and down 100s of times.

[burgermeister]

Originally Posted by rrnixonjr

The back side method is not working for me. Too difficult to get fine feeler gauges in place, too finicky for me after four hours of trying. I will now try the normal way.

Try rubber banding some popsicle sticks or other thin wood pieces around 2/3 of the length of the feeler gages. It's a convenient long handle, the wood isn't slippery when oily, and it prevents the gages from buckling when you try to slide them between the cam and the rocker. That worked for me, anyhow.

[Scott98]

[QUOTE=Gunter;3606759]

Originally Posted by Scott98

Scott:
Love to see that.
The 1/4" torque wrench would have to have a fairly small head and the socket has to be pretty short.
Can you post a picture of the whole tool? Wrench and socket together.

Please.

This link shows a picture of the socket:

Special Tool for Rocker Shaft Bolts

This link shows a picture of the torque wrench I used. Its an SK Model 74016:

http://www.amazon.com/SK-4-Inch-Micrometer-Torque-Wrench/dp/B0009WRKZM

Scott