I am ajusting my valves now, and don't see...

[rnln]

This is my second time I try this task, didn't do it right the first time. I am trying the lower one first. When reading many threads regading this task, many people saying they like to use the alen key to hold the bolt rather then the flat screw driver. Well, my cover is off now and I don't see that I have an option. On all of my valves, there is only the slot for flat head screw driver. Anyone has both?

One question though, how tight do I suppose to tight the nut? Last month, maybe I didn't tight it too tight and maybe it got loosen itself and it makes noise again after several days? only when the engine warmed up. I used a flat head screw driver to hold and an open end wrench to tight the nut by hand. Should I push it until I can't push anymore or should I hammer it with a hammer? :lol: I know I will get slammed for this.

One more thing, on the valve cover nuts. When I take them off today, all the crush washers "turned into the screw itself". I had to use a needle nose plyer to loosen them and screw them out by hand. Did I tight the valve cover nuts too tight?
Alright, under the car again.

Thanks.

[RoninLB]

maybe the allen is small enough to fit into the screwdriver slot ?

also see 101 Projects For Your Porsche p 58

I just lean on the nut to tighten. Probably comes to around 35-40 #ft

there could be other reasons for a valve ticking besides a nut coming loose.

[rnln]

After reading many posts, I have a feeling this task might better be for the pro, in the area of reliability of the engine. I am confuse when my hands are actually in there and carefully thinking about what I have read. Someone said it should be tight enough so the feeler can not be move (I assume back/forth), but can be able to rock left and right. Someone said it is like you are pulling a paper while someone standing on top of it. To me, that is imposible to pull. And while someone said only a little friction. I personally think all the above totally different. And the most important is too loose = valves noise and slowly damage valve guide. Too tight = damage valves guide quick without any sight.
Under the car again...

[Ronbo]

Valve adjustment really is an art. You get better at it the more you do it, but the 911 would be a very difficult car to learn on. Good luck with this!

[Jeff Higgins]

Too loose is always better than too tight. Too loose (within reason) just makes noise and annoys you; it will not damage anything. Too tight will not allow the valves to fully close and will soon burn them, especially the exhaust. Neither will ruin guides.

Porsche has a torque spec for both the lock nut on the adjuster and the valve cover nuts. Look them up in your manual and use them, at least until you develop the "feel" for how tight they are supposed to be.

As far as the "feel" on the feeler gauge, that's a tougher one to develop. It should slide freely between the adjuster stem and the valve. Do this: grab that feeler gauge between your thumb and index finger. Make sure it is oily. Squeeze on it no harder than you would pinch your wife's or girlfriends ni... you get the idea. See how the feeler gauge feels when sliding it back and forth between your fingers, that's about right.

[RoninLB]

although the valve adjustment is a simple process it can be intimidating.

even newbies that have done it many times have asked me if it was alright if they can watch my act. There was always simple questions that were answered with simple answers.

through it all is a respect for the guy's enthusiasm.

[bell]

i use a stubby flat head screw driver (easier to hold solid) and a wrench to adjust mine, one way to think of the actual adjusting/tightening part is to remember that a very minute turn of the flathead will make it loose or tight, the trick it so get the feel for the movement while tightening.

once you get the feeler positioned to where you can slide it sideways back and forth position your wrench and stubby screwdriver, when you feel drag on both sides of the feeler tighten the nut while holding the screwdriver securely and in place. once tight check the feller again for the same "drag", when you're happy with it remove the feeler, don't freak out if you can't get the feeler back in, i found that the .004 gap transfers to elsewhere in the valvetrain and can never ever get the feeler back in.....the gap is still .004.

on the cover bolts it sounds like you overtightened them.....but nothing to freak out about, maybe get a small torque wrench to be sure, if the washers are crushed i'd replace them....just good piece of mind.

roninlb has trained me well

[rnln]

Jeff,
really? There are many thread on this board saying too loose = noise and damage valves guides and = burn oil and = early top end rebuilt = $$.

I did this task several times years ago on the nissan 240z, and once on this 911 last month. man... under the car almost all day today, I have been tighten them and loosen them in and out several times. Loosen them as Jeff said above at the beginning, then I thought mine were that way, why noise? Then I got down again and tighten them all. Then I got scared of damaging valves or valve guides, and loosen them all again. Now they are tighten again.

Tighten as I still can be able to move the feeler gauge (.004") from left to right but have to wingle it first. I can not just pull it straight out. I have to wiggle it to get it out. Is it good? I think if there is room to use a straight gauge as on Japanese car, then it's much easier to tell. On our car, the gauge need to be shaped as an L and your fingers have to hold the gauge at the upper part of the L, harder to feel.

Someone (n this board) even said the gauge can not (or very hard) to go in. The nut has to be loosen before the gauge can go in. To me, as long as I can move/wiggle the gauge in there, I still can manage to get it in. The way I hold the gauge is with my thumb and my pointing finger, my middle finger is at the corner of the L-shape angle to push it in.
Note: my gauge is not straight but bent as an L shape.

If anyone in OC, Scal who has the experience and ok for me to watch and "feel", I hope I just can come and feel it.
Thanks.

Bell,
When you say "drag", you mean friction? The way I have mine now is lot of friction. I have to wiggle the bent L shape gauge to get it left/right, in/out. I still can be able to manage the gauge in there after I pull it out byt he method I wrote above.. so maybe it's not too tight.
Yeah yeah, I learn a lessen (on the washers) so I ordered the whole kit before I started. I will get more washers (a lot more) if I can fine them locally.

[GrantG]

I found this method to be VERY helpful on my first try:
http://www.pelicanparts.com/techarticles/911_backside_valveadjust/911_backside_valveadjust.htm

[2.7RACER]

I just helped my friend adjust the valves in his '90 C4 a couple days ago.

The "backside method" as described in my article referred to by GrantG above is designed to do a number of things.

First most folks suffer over the "feel" necessary to adjust with a .004" special feeler at the swivel foot to valve gap.

Using the "backside method" there is no need to develop any "feel". The no-go feeler gauge is blocked and the go feeler gauge slips in. Simple.

Throw away the special feeler holder that breaks and drops screws into your work area. Use a simple everyday feeler gauge set.

Don't loosen every single adjusting screw to fit the special .004" feeler in place at the hard to get at swivel foot.

By using a .003" normal everyday feeler at the rocker/cam cap, you can check if the adjustent is too loose.

Thus it is referred to as a "no-go gauge" It should not slip into the rocker/cam gap.

If the first test with the "no-go gauge" checks OK, then try to slip in the "go gauge" a .0025" feeler. It should slip into the rocker/cam gap. If it does not the adjustment is too tight.

If the .0025" slips in while the .003" does not, the valve is adjusted properly.

Do this first. You will find some of the valves require no adjustment.

Remember the adjusting screw is a 1.0mm thread pitch. This means from Zero lash to.004" at the rocker swivel foot is one tenth of a turn.

Very little movement of the screw to get the proper adjustment.

You can check your work simply with the no-go and go. The feeler either slips in or it doesn't. No guesing if you have the proper "magnetic feel".

Once you have used this procedure you can close up your engine with the confidence the job is done correctly.

This all works because the rocker ratio with the valves closed is approximately 1.4 to 1.

Divide .004" by 1.4 and you get a number between .0025" and .003".

With this method the tightest you can set the valve is .0035".

The loosest will be .0042".

Both well within the factory tolerance of +/- .002".

Even better, usually just under .004" so the valves will be quiet.

The "pros" that use the old method can benefit from this method.

It will speed up the job, with confidence it is done accurately.

[rnln]

GrantG,
Thanks. I read it before I started last time but when I was in there, I can't see how better since the feeler is so thin and "weak". Maybe I am a beginner therefore I just can't get it yet.

Anyway, I am done for the day. Thank you all for opinions. After a short test drive, I can see it's better but I still can hear a little, very little, noise (sounds like valves noise) when I open the door and stick my head out while giving it a little gas. Once a friend of mine, mechanic, said this is how 911 sounds so don't worry. I am not sure if he is right or is it really valves noise and can be corrected. Anyway, I got rid of maybe 80% of the noise today. Feel good
Part of me is telling to leave it to the pro so it can be done perfect. Another part is saying "again in couple weeks".
Again, thanks all.

[hcoles]

there are a lot of threads on this and it does take a bit of practice. The offset wrench helps a bit and cutting down the holder and/or blade makes it easier to get the thing in and out. You will get good at getting the blade in even when the tolerance is a bit tightish. Most on this bbs say the "feel" on the gauge ... should require a firm sliding force maybe with a bit of wiggle to get the blade out... this seems to get the adjustment quiet and not burning any exh valves. It is not a very great design in terms of adjustment but seems to work - IMHO - that's what I do, I'm no expert but have done probably 10 or so with the engine in the car and a few with the engine out of the car. I just love doing it with the engine out of the car.

[rnln]

Originally Posted by 2.7RACER

no need to develop any "feel"

Great, sounds very good. I will try it again with this method. Hopefully I can get it.

Originally Posted by 2.7RACER

If the .0025" slips in while the .003" does not, the valve is adjusted properly

How far does it slip in to count as "Go"? 1", .5", or .25"? Can you give me a hint base on your experience?

Thank you.

[2.7RACER]

rnin,
The "no-go" will be blocked where the rocker arm and cam contact.
The "go" will slip in as far as you choose to push it. One, two even three inches. 25, 50 or 75mm for you metric types.
It is pictured in the article.

[rnln]

Doug,
thanks.

[livi]

I remember this part clearly. The anxiety, the uncertainty, the worrying of not getting it right. The threads read over and over.

You know, I have a feeling you have already done a job as good as anybody could. Very meticulous. As you say, you have got rid of 80 % of the ticking sound so they are not as loose as before and if you could fit the gauge in the gap before tightening the screw, it can not be too tight. So, I think you should be proud of a DIY project well done. If you still canīt leave it as is, I would probably have a pro checking your settings instead of trying myself once again risking still not being certain. Having a pro checking it (likely giving it OK) you will then know you did it right and never worry about it again.

[jluetjen]

Originally Posted by rnln

One question though, how tight do I suppose to tight the nut? Last month, maybe I didn't tight it too tight and maybe it got loosen itself and it makes noise again after several days? only when the engine warmed up. I used a flat head screw driver to hold and an open end wrench to tight the nut by hand. Should I push it until I can't push anymore or should I hammer it with a hammer? :lol: I know I will get slammed for this.

I don't think that anyone answered this question. I would caution against over-tightening the lock nut. You shouldn't have to crank down on it with all of your strength. If you do, you may find that you end up in a situation where you can't loosen it next year, or worse deform the threads. I like to firmly tighten the locknut using my wrist muscles, but not put my whole arm into. If I'm straining to tighten it with just my wrists, I'm too tight. I'm most likely more in the 15-20 lb-ft range, 35-40 sounds a bit high to me.

The engine that I'm just rebuilding had had the lock nuts overtightened. All of the threads on the adjusters were distorted. As a result all of the adjusters had to be replaced. Adjusting the valves would would have been impossible for the previous owner of the engine.

[Tom '74 911]

Doug's (2.7RACER) method makes the process easy. Just keep in mind his statement re: 1/10th of a turn makes a difference in the adjustment. Some of the "purists" have scoffed at this method - but it takes the guesswork out of it and lets you know for certain if the valves are adjusted correctly before you close it all back up. I'm not particularly religious, but I'm I'm a believer in this method!

Tom

[RoninLB]

tightning down the spark plug washer is 20#

[rnln]

Even after tighten the nut, I still can push the gauge in there and wiggle it to move around. Sounds liek I am ok then. You make me feel so proud/good. If it stay that way after several long trips, I'll be very happy. Last month it only took several days of driving and the noise come back after the engine warmed up (10-15 mins of driving)

Originally Posted by livi

I remember this part clearly. The anxiety, the uncertainty, the worrying of not getting it right. The threads read over and over.

You know, I have a feeling you have already done a job as good as anybody could. Very meticulous. As you say, you have got rid of 80 % of the ticking sound so they are not as loose as before and if you could fit the gauge in the gap before tightening the screw, it can not be too tight. So, I think you should be proud of a DIY project well done. If you still canīt leave it as is, I would probably have a pro checking your settings instead of trying myself once again risking still not being certain. Having a pro checking it (likely giving it OK) you will then know you did it right and never worry about it again.