BallStuds

[gmask]

So I had hoped to recover some of the old ballstuds from my old cylinder head. I have 6 good and tight ones from another head but it turns out that all of the ones on the old head are totally loose!! I've ordered 6 new ballstuds.

My question is should I give the new ones any priority over the old ones?

I was thinking that it seems that the cylinder 1 puts extra wear and tear on parts so it shoud get priority.

The old head was leaking oil from the studs down onto the sparkplugs so maybe put the new studs on that side??

[240 Ed]

As far as leaking ball studs, before installing them into the head, coat the thread with non hardening Permatex. This will definetely seal them.

[ctaylor738]

How can a 130 ball stud leak?

Isn't it is a solid piece of metal screwed into the head?

Please enlighten me!

[240 Ed]

Well, the ball stud is continually soaked in oil, being that it is in the cam galley.
I suppose that if the stud had been removed, or the threads buggered, or just cuz, the oil would find its way down and out and onto the spark plug.
I was suggesting a way to seal the threads.

Also, Loctite makes a "thread sealer" that works well.

[gmask]

Originally posted by ctaylor738
How can a 130 ball stud leak?

Isn't it is a solid piece of metal screwed into the head?

Please enlighten me!

There were several that were so loose that I could finger unscrew them which would explain how oil could easily get past them. I also noticed in one of the manuals that it is recommended to add a 2mm washer if they cannot be tightened to the specified torque. I haven't found the specified torque yet but since the head is new the threads should be extra tight and the studs on the sparkplug side are going to be all new. I will probably use some loctite as well.

The ball part of these I think is supposed to have a torque of at least 20 foot pounds. Many of the ones I threw out had little to no resistance.

[ctaylor738]

But even if they were out of the hole entirely, where would the oil go? Don't they screw into a blind hole in the head? I confess to never having one out of my 130 0r 110 engines.

The torque setting for the 380SL is 60 Nm for the studs.

[gmask]

Originally posted by ctaylor738
But even if they were out of the hole entirely, where would the oil go? Don't they screw into a blind hole in the head? I confess to never having one out of my 130 0r 110 engines.

The torque setting for the 380SL is 60 Nm for the studs.

Nope the hole goes straight through. If you use a mirror you can see that the stud end is just above the sparkplugs. On the other side the studs go through to the air/exhaust passageways.

Anybody know the conversion for Nm to Foot pounds?

[240 Ed]

Look in the Haynes manual in the engine specs and you will probably find the correct torque in ft/lbs. If not, you can match it up with something with the same metric.

[ctaylor738]

Indeed, the Haynes manual shows 100 Nm or 72 ft-lbs.

[Arthur Dalton]

Nm X .74 =ft/lbs

Ft/lbs X 1.35 = Nm

[gmask]

Originally posted by ctaylor738
Indeed, the Haynes manual shows 100 Nm or 72 ft-lbs.

You beat me to it... I still haven't found the torque setting for the ball part ..I think it is 20 ft/lbs. Haynes only mention the torque for the whole stud.

[Arthur Dalton]

<< I still haven't found the torque setting for the ball part >>

Ball spec is 14-25 ft/lbs.

This is only a thread resistance spec. range for the ball when adjusting the valve lash. Less than this and the ball will not lock
at it's set position with the self locking threads. [ resulting in valve lash not holding].

[gmask]

I finally got all the rockers back in.. setting the valve clearance was tough. The new studs are impossible to turn safely with the crow foot wrench. Many of the valves had to be adjusted by taking the rocker off and then turning the cap with a socket, then put rocker on and test clearance etc. All in all a very good workout. These things better stay put for ten years..

[vince]

I'm having trouble understanding the oil leakage (although I seem to remember this coming up in the MBCA STAR many years ago). If the hole for the stud went all the way through to the combustion chamber (which would be "right above the spark plug") then combustion gas could leak into the valve cover. Also, buy the correct crowfoot wrench. The adjustment interval is 12,000 miles. And they do require periodic adjustment. After all, valve seats wear and the ball studs wear. In fact, if you cannot get a reliable adjustment, it could be that the ball studs are worn. They tend to wear to a cone shape, rather than ball shape.

[gmask]

Originally posted by vince
If the hole for the stud went all the way through to the combustion chamber (which would be "right above the spark plug") then combustion gas could leak into the valve cover.

The sparkplug fits into a recess the threaded hole for the stud goes through to the top of the recess .. the combustion chamber is rather shallow and only has the three holes.. the spark plug, inlet and outlets. I noticed when I was installing the new studs that the threaded hole that had been leaking previously on the old head was especially easy to screw into on the new head. I can't think of a reason for this to be so but it is apparently apt to happen with the m130 head. I used thread sealer on all the ballstuds so hopefully I won't get leaks again.


I do have the correct stahlwille crowfoot but it tends to slip off unless I put sideways pressure on it which is hard when you ned to use both hands on a breaker bar just to turn the thing..I'm not kidding theya re that stiff.. after the struggling with the first new ballstud I worked the others back and forth some to try to loosen them up a bit.