Special tools needed for valve adjustment?

[tranzor_Z]

Hey All,

I was all set to adjust the valves on my bone stock '73 240z, however when i went to actually adjust one of the valves clearance i found that a 14mm was almost to the point of slipping off the adjustment nut. A 13mm is too small and just for kicks i tried a 9/16 its the same as the 14mm.:sleepy: .

So i'm just wondering if i just need to use an adjustable wrench (which i would hate to do) or is there a special tool needed that is a 13.5mm or something. I guess i could try to file out a 13m so i get a tight fit.

What i am really afriad of is round out the adjustment nut itself.

Also from what i've checked all the intake valves were snug at .010'' but ALL the exhaust valves were way less than .008", hmm. I sure do need to get these things right.

Any help will be very aprecctiated.

-Thanks

[MikeW]

It really is 14mm. I've heard others claim that some tool vendors make wrenches than aren't quite right but I've never seen that myself. It sound like perhaps a previous owner used an adjustable wrench and that's why it seems off. I suppose you could try a pair of vise grips but those kind of also fall into the category of tools to use only in an emergency.

[2ManyZs]

You should only need a 14mm and a 17mm to do the valve if I remember right... sounds like someone along the way has overtightened the lock nut and it's started to round off. I'd replace it, but first you'll have to get it off. I wouldn't use an adjustable, better to use a good set of Vice-Grips or you run the risk of rounding it off even more with an adjustable.

Or perhaps, it's your wrench that you are using that is spreading... a lot of the less expensive brands of wrenches have very weak open end jaws and will flex enough to cause a lot of rounded off nuts and bolts.

[Daniel]

I've had luck with a couple of tricks.Insert a small flat blade screwdriver into the gap left in the wrench and try to crack it loose or use a stack of feeler gauges as a filler.Just a thought.

[tranzor_Z]

I really appreciate all the replies.

I noticed a few things in retro-spec while studying today.

1. I was trying to loosen the entire assembly via the 14mm adjusting nut. After i loosely put everything back together this hit me, DOH!:stupid:

2. I was being ultra gentle becase i didnt want to damage the componets, maybe i should just revert to blunt force. Break out the breaker bars.

Again thanks for all the replies i wish i didnt have to study so much other wise i'd have this done, but i guess having a better job is worth it , then i can buy more parts for the Z.

-Later,

-Steve

[280zx Fever]

1. get a set of vice grips

2. get that old nut off and go and get another.

3. readjust

dont try to make it work just get another so it does work withouht trying

[Victor Laury]

You do not turn the 14 mm first. You turn the 17 mm lock first while holding the 14mm. After the 17mm lock nut is loosened, the 14mm turns without resistance. If the 14 is rounded off, it's because sombody forgot this during a valve adjustment.

Think of it as a 14 stud that srews into the head. On it is the 17mm lock nut. the lock tightens down on the head surface to lock the stud in place.

[tranzor_Z]

Hey guys just wanted to let you all know that i figured out the 17mm thing night before last.

I find it strange that in not one article or in the haynes service manual i have that it just doesnt say to turn the 17mm. Hmm, oh well i hope this might help someone in the future.

The car is running absolutly fabulous now. It starts right up has a much smoother idle and the gas milage has gone up considerably just in the driving i have done since i got it done.

Thanks to all the replies , i only hope i can learn enough quickly to help someone else out.

Now on to tuning those darn dual Weber DGV's...sigh.

-Thanks

-Steve