Dial indicator valve adjustment method explained

[Mukilteo911]

I read about 20 posts on valve adjustments and could not find a complete explaination on how to do it properly using the dial indicator. I thought I would ask someone to describe it in detail. I have worded the subject heading clearly so that others can find this more easily in the future.

Someone who uses the Dial indicator valve adjustment method please explain the procedure.

Thanks

[HawgRyder]

A dial indicator measures vertical movement.
Therefore, you want to get the rod of the indicator as vertical as possible in relation to the movement of the rocker arm.
If the rod touches the rocker arm at the valve end of the rocker, then when the valve is closed, the diference in pushing in and pulling out the rocker will be the clearance or movement of the indicator.
I'm not sure if you can get the indicator into the far end of the rocker...and if not...the other end clearance would have to be multiplied or divided by the rocker ratio to get the correct numbers.
Potentially the indicator method is more precise than a feeler guage...but probably harder to do.
Bob

[Mukilteo911]

So basicly you:
1. Get the cam in the correct position to adjust the valve.
2. Set dial indicator vertical to the valve stem.
3. Place the rod of the dial onto the rocker as close to the adjustment screw as possible.
4. Preload the dia for accuracy.
5. Adjust the screw so that when you move the rocker up and down the dial indicator shows .004 movement. Tighten down lock nut to spec and retest for .004.
6. For assurance rotate the engine and check the measurement again.

[makaio]

The feeler gauge is much easier to understand and is really no that hard to do.

But Bob described the dial gauge pretty good.

[HawgRyder]

Mukilteo....you got everything correct except #2.
The dial indicator will be vertical (above) the valve stem.
Bob

[Chuck Moreland]

Good luck trying to use a dial indicator with the engine in the car. You might reach a few rockers, the rest just don't have the clearance to get the indicator in place.

[ischmitz]

Is that even a valid method to adjust valves with a dial indicator?

With the oil between the valve stem and the rocker arm adjuster I am wondering if the dial indicator gives accurate readings. Especially with the heavier oils I have to sometimes slide the rocker sideways to break the oil film between the mating surfaces before I recognize any clearance. Also the swivel foot is sort of loose on the set srew throwing in another uncertainty.

Ingo

[Rot 911]

I used the dial indicator to adjust my valves when I finished up my engine rebuild and the engine was out of the car. The thing I found it most useful for was to get an idea of just how much drag there should be on the feeler gauge when the valve is adjusted properly. My "magnetic" drag setting ended up being about .005. When properly set to .004 the feeler gauge is actually quite difficult to move.

[Superman]

I prefer the dial indicator method. JW does not use this method, but I think that's because he's MUCH quicker with the feeler gauge. The feeler gauge method is quicker. But the dial indicator method does give you some interesting information.

You've got the basics correct. My exhaust is backdated, my heater system is backdated and my A/C is removed. So, access to all twelve tappets is a cake walk. When you use your hands to rock the rocker back and forth, be sure to make sure it travels ALL THE WAY in each direction. Smash that oil. Wiggle the rocker a little (rocker shaft wear can cause the rocker action to be twitchy). The .004" spec should be created between the FARTHEST points you can get the rocker to travel. In other words, just like the feeler gauge method, rookies will make the mistake of adjusting the lash too big. Too much clearance. The gauge should just barely move .004" when you rock the rocker AS FAR AS IT WILL GO in each direction.

[cary]

Originally posted by Kurt V
I used the dial indicator to adjust my valves when I finished up my engine rebuild and the engine was out of the car. The thing I found it most useful for was to get an idea of just how much drag there should be on the feeler gauge when the valve is adjusted properly. My "magnetic" drag setting ended up being about .005. When properly set to .004 the feeler gauge is actually quite difficult to move.

Ditto on Kurts thought. I really lets know what the feeler gauge method is supposed to feel like.

[Mukilteo911]

Great feed back, not at least we have a complete description of the process. I figured I would do it with the dial and then check with the feeler to make sure I was doing it right with the feeler. I have done it 5 times with the feeler four of the five were good adjustments checking by the ears anyway. But I would hate to burn a valve so I wanted to start checking. Whats a little time when it comes to getting it right.

[5axis]

I had posted these some time ago on the rebuild page. I think it was a thread about tools.
Here is a Kant twist clamp and a starret flexible mag base holder, sans mag base. A portion of a "indicol" and a test indicator. I have quite a assortment of gages, indicators and various holding equipment.

After doing a few I found I could feel my way to about +/-.001 .

[fuelie600]

Has anyone tried a Gunson's Click-adjust?



The tool uses the long lever to loosen the lock nut and the knob turns the adjuster. You turn the adjuster in until there is no gap, then back out the adjuster a certain number of clicks to the proper gap, then lighten the lock nut with the lever. It's very fast and easy. It also compensates for uneven wear on the mating surfaces of the shoe and valve - a feeler guage will bridge the worn surfaces and result in a more generous gap.

You must first calibrate the tool to the thread pitch of the adjuster. The adjuster knob emits clicks when it is turned, so you calibrate the gap in clicks with a feeler guage. Here's a better description.

These tools are popular with old British cars. I'm planning to try it on the 911 in a couple of weeks and post the results.

[caliber60]

I think the important question is, can you adjust all the valves with the engine in the car? I can barely fit my hand to adjust the valves in the back. I mainly did it feel. How can you fit a dial indicator in there?

[Mukilteo911]

my car has a carb engine and older exhaust so it is easy to get around.

We have to know how well the Click Adjust works, sounds cool.

[William Miller]

Just getting on the subscription list.
Some one once asked me if you can do the adjustment by eye.
(Watching the adjuster screw and hold it as you back it out.)
I theory it works, but you really can't see what your doing.
This gadget is really doing the same thing. Once the adjusted is dialed in tight it should back it out 1/10 a turn = 0.1mm.

I think this is the right amount.

[fuelie600]

It's a little more precise than by eye. It resets when you screw the adjuster closed, then clicks at certain intervals on the way out.

[5axis]

Originally posted by caliber60
I think the important question is, can you adjust all the valves with the engine in the car? I can barely fit my hand to adjust the valves in the back. I mainly did it feel. How can you fit a dial indicator in there?

Mine is a turbo so the enging comes out for a lot of things. Mostly for more/better go fast stuff, but that's another issue.

It's not a big deal.

I think the NOVA guys would do a drop for cheap beer.

[RoninLB]

Originally posted by Mukilteo911

We have to know how well the Click Adjust works, sounds cool.

I'm always looking for more toys.

These 911s aren't as much fun as leaning over the fender to adjust a Chevy with a running engine.. small blocks with higher comp and exhaust was nice. big blocks w/marine exhaust was wild. I will still use a vac gauge at the same time, so there is a lotta reving going on..
so as long as you had ventalition..

the self imposed oil bath & oil vapors was cool.

[William Miller]

The NOVA guys may even buy the beer!