Lessons Learned - Valve Adjustment
 

Was time for my second annual valve adjustment, while setting a personal best for this (2 hours), I made some observations...which led to what we call in the military, "Lessons Learned". So, here is my AAR for my latest valve adjustment:

1. No matter how hard you try, you can't get the feeler gauge under the head stud.

2. If you bend the feeler gauge enough (to get a better angle) it will break, and break, and break.

3. Whom ever designed or is responsible for the location of the cylinder 3 valve....should be shot...enough said.

4. Intake valves seem to hold their position (except #5!).

5. Exhaust valves have an attitude...always need to be held with the screwdriver.

6. Along with that, while trying to tighten the nut, no matter what you do, the screw will twist, the feeler gauge slip out, and any remaining oil (x12, and magically appearing from no where) will make your hands so slick you won't be able to hold any tool, let alone a screwdriver!

7. What is the definition of "magnetic resistance" anyway?

8. If this is your first time (or second) it would probably be a good thing to check your work (how do I know this?).

9. Questioning your German mistress's morality doesn't help (or was that cursing it...oh well, doesn't matter now anyway). Patience is a virtue, and the mistress appreciates it too.

10. Alcohol (ok, beer) is essential once the task is complete.

Island...love your feeler gauge tool, also got to try some new offset wrenches...also awesome!

Enjoy and have a Happy New Years!

Rob:

I experienced my first valve adjustment for my 87 Carrera Saturday. It was not fun. To make a long story short, after warming the car up and making a couple hard acceleration runs, my car developed a sudden loud clicking noise. I immediately shut it down and coasted home. I had my car flat beded to a very reputable Porsche mechanic. He said I was very lucky because a nut came loose from one of the valve adjustment screws and it was sitting by the oil return tube waiting to make its way into the motor.

He adjusted the valves for $250. My car's acceleration is a lot crisper than I have ever noted before. What a relief!

I am actually glad to have had the experience. I learned more about my car. I know I can get through a valve adjust if money is too tight or I feel like torturing my self. And, I learned to double check everything when working on a critical part of the car. After feeling the difference that a proper valve adjustment can make, I seriously doubt I will try it again. It is $250 well spent in my book.

Mike

I did my first valve adj. a few weekends ago, and while it was a PITA, I didn't find it "difficult" I found it very difficult to check my work, trying to put the feeler gauge back in was almost impossible. I adjusted them and then checked the gap by shaking each rocker arm and doing a calibrated feel to make sure that I indeed had a gap. Started her up and no valve ticking, improved idle and seems to run a little better. A neighbor who has an 84 coupe told me he pays $800 for a valve adjust, oil change, all filters, spark plugs, rotor, and dizzy cap. While I can understand that, it seems a little rich, who knows, maybe his mechanic does a little more also for that money, I know his mechanic doesn't adjust the emergency brake cause he told me it doesn't work. Thinking about it though, when you include oil, filters, rotor, cap, plugs, valve adjust gasket kit and filters your probably talking $200 (I haven't checked). You gotta factor that in as well.SmileWavy

I just did my first valve adjustment yesterday and it took two 4-hour sessions. And now tap tap tap. Oh well, at least I learned something. Now I have to decide if I want to find the tapping myself or have someone do it for me.

Erakad, your findings truly hit home. Here are a few more:

The feeler gauge will NOT let you check your work after tightening the nut.

The gap will mysteriously expand after you have tightened the nut.

Three Advil Liqui-gels are required before, during, and after the job.

Tape your right middle finger before you attempt to loosen the nuts.

Pelican Parts gasket set includes the nuts and washers...sweet.

You will not want to double check your work, but you should.

The tap tap tap noise means you have to do it again.

Razor, yes did miss a couple...

Like....knock on wood if your head studs are still in place, extra points if they're still tight

Extra batteries for the flashlight...more if you're slow...like me..:)

Ok the truth...I haven't finished the check....I went to a movie instead and will do the check tomorrow, so sue me. :)

Razor, if you're redoing the adjust, what about oil? Are you going to drain the oil again...or, I think I read somewhere you can jack up one side and retain most of the oil.

I performed all the other service items (oil change, filter change, air filter replace, fuel filter replace, plugs, rotor, & cap). With the savings from that, I am more than happy to pay $250 once a year to have the valves adjusted by a pro.

Mike

True dat. paid $250 for a pro-style valve adjustment over the summer. Money well spent. SmileWavy

Well said my good man... Well said.

Now, Chris, you were the guy that said that it was cheapest to be your own mechanic. That only works if you can do the work correctly!! :rolleyes: A bad valve job will cost you significantly more than the $250 you saved. Do you think that the weekend mechanic can successfully adjust his own valves?

Is $250 the going rate in Chicago for a valve adjust? And does it cost the same to adjust the valves of a 73 as an SC as an . . . . ?

thanks

larry

I tried to adjust my valves on my previous SC 4 years ago, I never could get them right, the 2nd time I got closer but a few months later I developed a backfire and popping on deceleration took it in and one of the valves had worked loose from the lock nut. The elephants foot gets tricky as they wear and it makes it difficult to get a good measurement for the clearance, $250.00 is money well spent for a pro.

It was much easier to drop the engine/trans, replace the clutch and fix my bad 1st gear syncro than do a valve adjustment.

Hugh:

I have to dissapoint you. Unless you run synthetic oil, you can do it for under $100 in quality parts. At least on my SC, PP sells the tuneup kit with all parts you mention for around $80.

But I was surprised too. That was the first time that I felt that buying parts for the 911 wasn't so expensive after all. My wife did watch me unpack the stuff in the evening. She smiled and said understandingly: "Spending some money, eh?" I said: "The whole pile of stuff is only $80". She was suprised, and it looked like I had a cheap hobby - for this order... ;)

George

All the mechanics I have talked to have become conditioned to "touch". I guess its just plain experience. I botched a valve adjustment job last summer as well and had the car towed and was really pissed at myself for the failure. After all its not a hard process relative to the mechanics of it, but I find its the lack of good access, equipment and design. Some are better then others at this game. We all learned though that a little mistake can be very costly!

Feelin no shame'

Bob
73.5T

Larry,

It depends on what a "weekend mechanic" means...

The guys who's sole tool collection consists of a "catch all" kit and who think a pair of vise grips is a good universal tool should not be doing a valve adjust....

However someone that has changed oil on several cars, can gap a spark plug, and knows how to use a torque wrench should be able to do this.

Not casting dispersions at those who have tried and failed here, stuff happens and we've all made mistakes. This isn't a mechanically difficult job per se, I think even those who had trouble with it would say that, but it is a precise job that can be fustrating. (Which I think is the point to the top 10 joke above)

I would imagine the going rate in CHicago is higher.

I adjusted the valves on my SC last weekend.
A couple more to add to the list:

It is so much easier to adjust the valves with the engine out it almost makes it worth it to pull the engine ;)

Do not try to custom bend the feeler gauge (see above, it happened to me too).

If the feeler gauge breaks it will usually do it while adjusting the last exhaust valve.

You will not be able to get the broken feeler out without loosening up the valve you just adjusted.

Pelican sells replacement blades, I have them on order.

I should have ordered the island adjusting tool, but since I had the factory style tool I figured it was good enough. Oh well.

I too checked my work by trying to wiggle the rocker after tightening the jamb nut.
I came to the conclusion that it should wiggle side to side a little but should have absolutely no rock in up and down (clearance on the feeler).

A few more tips:

1) I like to adjust all the exhaust valves then come up top to do the intakes, just personal preference. Doing the relatively easy exhaust valves in repetitive order will give you a good feel of a proper/consistent gap. Then you go up to the intakes, you'll remember what a good gapping feels like.

2) Leave the feeler gauge between the valve and the elephant foot when you are adjusting. It will save you from trying to slip the tool back in.

3) Snug the elephant foot down on the feeler gauge to the point where you can barely drag it through, then tighten up the lock nut. I noticed after tightening the locknut, the gap will open up just slightly and give an almost perfect feel.

4) A mirror on a stick is almost imperative to get to #3 and #6 intakes

5) Loosening the valve considerably is sometimes the only way to get the feeler gauge between the valve and e-foot. Go to tip #3.

6) MarcA's tip is to use a .005 feeler for final inspection. If you can slip the .05 all the way in, it's too loose.

Razor--

I had some tapping after my first valve adjust and was able to locate the offending valve (#6 intake, of course) with one of those mechanic's stethoscopes.

Like I said, I hadn't checked, but your right. For my 84 PP lists the maintenance kit at $113, plus tax and shipping, goes to about $130 plus $15-20 for engine oil, but not Swepco for the trannie, and your at $150

Good idea Targa911man. I'll get one today.

Also, is Island's adjustment tool different than PParts tool? If so, where can you get it?

Get two of Island's tool and put .005 stock in one and .004 in the other (and don't forget to mark which is which). Like Charlie and Marc, double check your work with .005 stock. Stainless steel stock is not nearly as brittle as the normal feeler gauge material and does not break as easily. I've done 3-4 valve adj. jobs and always with the engine out of the car. I think it would be worth it to pull the engine just for the ease of it all and also to replace the misc. little stuff that you can only do then.

Razor; the tools I've had made are backordered. . so to speak. (the guy I've had building these has been busy with other stuff)

tolerance & "feel":

Every measurement has a tolerance associated with it. . . there it is.
(.004" ± .002" per decal underside of rear decklid)

http://forums.pelicanparts.com/uploa...1070131966.jpg

So really, if you can pull the .004" feeler gauge out of the gap, w/out cussing, they're not too tight. And Richard, maybe go to a .003" and .004", go-no-go set-up. . .whatdaya think?

Wow- I'd never noticed that before. So according to factory the range of 0.002-0.006 is acceptable! It seems 0.006 would lead to v. noisy valves?

After I did my valve adjustment on my '87, I think paying $500(Los Angeles price) is too much. Out of 12 valves, I only had to adjust 2 valves. Rest of them are just checking making sure it's within spec. It took me almost a month. I got frustrated, leave it along, come back next weekend. I know the valves are not designed to be adjusted with engine inside the car. If you take out the engine, it would be just like any other cars(ex. BMW 325i). Would you want to take out the engine just to adjust the valves? Probably not. It can be done with engine in the car. A mirror will help but not too much. I did mine mainly by feel. Some of the valve position do not even allow you to look at the valves. You just have to stick your arms in there.

LeSchander didn't mention that he also drops the engine to check the oil.

Yep, I follow the tolerance shown under the rear deck lid. I set my '87 at a tight .004", (actually .004" honed to .0035"). Nice and quiet. I suppose you could go to .003" and all would be well, maybe a loose .003"?

Chris:

I do understand what you are saying. Well, I know the difference between an open end wrench and a box wrench, have changed the oil on a few cars, and know what a spark plug looks like ;) (that is what you said, wasn't it?) Now, all I need is a friendly mechanic to take me under his wing, and in exchange for some sweat and banged knuckles, teach me some of the simple things. (hint, hint) :D Hey, Naperville isn't that far away!!! :eek:

But I've got plenty of time till spring and the arrival of green grass, green leaves and the Green "E".

larry

Was going to do my own valve adjustment in both cars this week. Forget it now. I'll farm it out and save on the towing!

Mine are noisier after farming it out than they were when I adjusted them. I'm going to check 1 or 2 & if the clearances are good I'm going to assume its wear on the elephants foot, or rocker thats causing the noise.

Cantdrv55 this is all in fun. Doing the valves gave me much pride. I didn't even know what noisy valves sounded like until now. And now I'm not afraid to pop the valve covers and poke around. Soon I should be able to say that about an engine drop. That was funny Targa911man.

The $250 I spent for the "re adjust" included new gaskets, nuts, washers, and one quart of Mobil 1. I live in Los Angeles County and I went to Nardi Motors in Whittier, Ca. My car has received service from Nardi Motors for several years from PO's. Mr. Nardi performed the adjustment himself. He is a veteran Porsche mechanic and has campaigned some serious 911 race cars over the past few decades. I knew I was in the right place when I pulled into his shop and saw a couple wild 911 race cars being prepared for customers.

I am glad for the experience, but there is a certain peace of mind knowing the valves are adjusted correctly and my motor is running at an optimal level.

Mike

P.S. This valve adjustment thing must be like having a baby. I hated it during the experience and immediately after, but I am already thinking I will have another go at it in 10,000 miles...

So here we go...did the recheck today...4 times...just to practice. Wish I had known the range, I would have left them a bit tighter. Sounds like I have 1 tapper...maybe on #6...but on the intake, so easier to deal with. I listened thru a long screw driver (like my daddy taught me), but didn't hear anything, but that was only good to #5, hmmm. As I recall, #6 felt great, any harm in just leaving it?

Oh, armed with the above, I'm going to err towards tighter than looser.

Oh, armed with the above, I'm going to err towards tighter than looser.
I hope you meant looser than tighter

How about using a dial indicator??

I had tappers on 1, 5, 2, and 6 intakes. Since I didn't take the spark plugs out, I couldn't turn the engine. So after about 1 hour to adjust the belt tightness (getting those washers to line up are a b$tch) I quickly tightened the intake valves. No more tap tap tap. I used one of those $10 stethoscopes from the auto store to locate the tapping. Six was the worst. I broke a feeler guage and 123shifter suggested using a magnet to get the broken piece out. That worked. Now I'm ready for the track.

Anyone near Wichita, Kansas Jeff Baxter at Oversea mtr's
does the valve adjust for $150.00 plus parts and doesn't care if you bring your own!Besides I've known the Guy for 35 years and trust him without question. Not quit JW but at least I don't have to drive to the nw for service.

Keith Epperly 87 slant nose turbo look Carrera cabriolet

I've been blasted by others before on this ( Eric Coffey) but if you're comfortable with the spec range...at least know this:

The screw used for adjustment is a 8mm x 1 pitch screw. 1/10 of a turn from completely closed is the *ideal* target of 0.1mm ( about .004 inch). However, taking a quarter turn of your screwdriver blade and cutting THAT in half is 1/8 turn.....equals spec plus a "scoch" of extra. Always better somewhat loose vs somewhat tight ( that can burn valves).

YMMV....so no burning slams.... OK?

---Wil Ferch

You bring up an interesting point. Last weekend, as part of my engine rebuild, I timed my cams and then adjusted my valves. I had the dial indicator all set up so I thought I would see how close I was on the valve adjustment. What I learned is that to get the correct adjustment of .10mm (.04in) the feeler gauge is very difficult to move under the elephant's foot. I don't mean "magnetic drag" that some refer to on here, I mean almost too tight to pull the feeler gauge out. Every time I went with the "magnetic drag" my dial indicator would show around .12mm for a gap.

The thing that helped me the most was using a micrometer to get a "feel" for how tight the gauge should feel. Like Kurt mentioned, I found out that the correct feel is a lot tighter than I thought and a lot tighter than most people describe.

Adjusting your own valves is a huge PITA the first or second time you do it, but is gets a lot easier once you get comfortable with it.

KurtV:
Maybe what you're experiencing is this:
I've mic'd various Porsche .004 feeler blades and all were .0042 to .0046

---Wil Ferch

Interesting. Maybe I shall get a micrometer before I try again. I suppose that would give me the "perfect" example of what .004 feels like with the feeler. I followed the "slight drag" terminology and ended up loose. In all fairness though, I think I got all 12 equally loose.

I use an aggresive timing: 13 degrees BTDC. After the valve adjustment, I starting getting some pre-detonation until the engine warmed up. I loosened the 13mm nut and twisted the timing down a degree or two and problem solved.

Is there any coorelation between valve adjustment and timing or was that just coincidence?