mercedes Ball Studs 6 Cylinder

[aluminum]

1966 / 1967 Ball studs : 6 Cylinder 250
What kind of " sealant " should be used installing them ?
I was thinking Permatex Aviation but perhaps a bad choice
I know they can leak Oil if not sealed > I am swapping a Head out and some
of the Ball Studs are worn but the Head is Great

How about the Torque down of the Ball Studs anyway ? just how tight should they be ?
My Book says 58 LBS Cold for the head and 72 LBS for " Rocker Arm mounting bolts ?" ( do you think that means Ball studs ? )

Same Motor 250 6 : Valve Guides : One head seems to have what lookslike Copper or Copper Alloy . The Other Head has Bronze or Brass like looking Guides

? do they interchange ? the 1966 Head Has the Copper looking Guides

Thanks for any Info

[t walgamuth]

Originally Posted by aluminum

1966 / 1967 Ball studs : 6 Cylinder 250
What kind of " sealant " should be used installing them ?
I was thinking Permatex Aviation but perhaps a bad choice
I know they can leak Oil if not sealed > I am swapping a Head out and some
of the Ball Studs are worn but the Head is Great

How about the Torque down of the Ball Studs anyway ? just how tight should they be ?
My Book says 58 LBS Cold for the head and 72 LBS for " Rocker Arm mounting bolts ?" ( do you think that means Ball studs ? )

Same Motor 250 6 : Valve Guides : One head seems to have what lookslike Copper or Copper Alloy . The Other Head has Bronze or Brass like looking Guides

? do they interchange ? the 1966 Head Has the Copper looking Guides

Thanks for any Info

I am no expert and do not have a book at hand at the moment but I believe I know the answers:
1. What are you sealing? The threads on the ball stud? If so I would only use what is recommended by mb. There is a torque spec and if the threads are worn too much the adjustment will not stay put.
2. Ball studs are not the rocker mount bolts.
3. Valve guides are pretty simple and whatever is available that is close in size your machinist will be able to make fit, I suspect. And probably the material can vary.

Good luck with your old benz! I used to drive them....have owned three fintails back in the day....a 190c , a 220s for parts and a 220b. Excellent cars but very rust vulnerable.

[aluminum]

Yup Rocker Arm Ball Studs > my Book was right
and Rocker Arm mounting Bolts " Are Ball Studs "

Thread Sealant Vaires : I know this is Important
moly under the head and the liquid PTFE (pipe dope) seems to be common
still working on that

I noted what looked like Dried Pipe Dope on the Ball Studs when I removed them .

The Top of the Valves has a Shim where the Rocker Arm hits
You can use thinner ones if you can't get Adjustment clearance

[t walgamuth]

Can you post a picture of the place it says the rocker arm bolts are ball studs please? Also please show a picture of the shim where the rocker hits the top of the valve?

[aluminum]

Did that allreaady last post just view the " Attached Thumbnails "
just look back > or as I did Just Google it

Or just look here Mercedes-Benz Rocker Arm Ball Stud
https://www.*******.com/Mercedes~Benz-parts/Rocker-Arm-Ball-Stud/

Thanks

[Frank Reiner]

Originally Posted by aluminum

1966 / 1967 Ball studs : 6 Cylinder 250
What kind of " sealant " should be used installing them ?

How about the Torque down of the Ball Studs anyway ?

Originally MB called for the use of tallow to coat the threads of the shell of the ball studs. The animal fat serves first as a lubricant for the threads in the aluminum head, and over time, with heat cycling, cokes to form a retaining compound. Lard could serve a similar function. Oil sealing is not an issue; any leakage past the threads will be very small, and in any event is internal.

Tightening of the shell in the head is ~ 60 lb/ft.

[t walgamuth]

Originally Posted by aluminum

Did that allreaady last post just view the " Attached Thumbnails "
just look back > or as I did Just Google it

Or just look here Mercedes-Benz Rocker Arm Ball Stud
https://www.*******.com/Mercedes~Benz-parts/Rocker-Arm-Ball-Stud/

Thanks

That picture was appreciated but does not show what I asked.

[aluminum]

Originally Posted by Frank Reiner

Originally MB called for the use of tallow to coat the threads of the shell of the ball studs. The animal fat serves first as a lubricant for the threads in the aluminum head, and over time, with heat cycling, cokes to form a retaining compound. Lard could serve a similar function. Oil sealing is not an issue; any leakage past the threads will be very small, and in any event is internal.

Tightening of the shell in the head is ~ 60 lb/ft.

60 LBS for the Ball studs Thanks Frank that sounds right Cold
I see several mentions of liquid PTFE (pipe dope) or similer product
I noted some off white crud on the threads removeing them I bet that was dryed Taallow or pipe dope.
I was asking because I want to try to get it right Thanks
My impression is that its easier to swap out the entire Ball Stud with adjustment stud as a unit . I have ones on a cracked Head I can use on the Used Head thats in good shape excepting the worn adjustment studs on the Rocker Arm Ball Studs . My Take on it is that turning the Adjustment Studs
all the way out and in seems to get them to loose for my likeing
Used an Impact Gun for removal as a unit they get tight ( 24 MM )

[Benz Dr.]

It helps if you understand how the ball stud works. It's also important to keep rocker geometry in mind and it's also easier to place a purpose-made shim under each cam bearing to raise the cam slightly. If you don't want to remove the cam then you can get thinner lash caps but since you will likely need 12 of them it's also going to cost more than the cam bearing shims.

[aluminum]

Originally Posted by Benz Dr.

It helps if you understand how the ball stud works. It's also important to keep rocker geometry in mind and it's also easier to place a purpose-made shim under each cam bearing to raise the cam slightly. If you don't want to remove the cam then you can get thinner lash caps but since you will likely need 12 of them it's also going to cost more than the cam bearing shims.

Thank You Doc Good Info
I shall Keep that in mind as I proceed . I have seen these Shims for sale .
I have never seen any Shims on any of the 3 250S MB heads I disambeled so far but no doubt I just have not run into them yet .
I did learn the hard way how to tell if such an OHC Head has been Milled allready
by just looking at it from the top along the edge IE > the distance between the
Valve Cover sealing edge and the actual Head itself . That Edge should stick up
about 80 / 100 Thousands my guess by Eye . Right away if less it's Milled you can see it without removing the head from Block . I mention this Because I looked for a Used Head from Salvage and it's a time saver. As well you can place a straight Edge along the same Valve cover sealing edge checking for warpage along the top*( Most often if a Head is milled your talking top and Bottom )
What ? Do you think replacing Head Bolts is that a MUST DO END OF STORY ? * * They look perfect but they are Torque to yield ( TTY ) Bolts
I guess you just tighten in sequence ending up with about 60 LBS then an Extra 90 Degrees ( a 1/2 Turn extra ) * Does that sound right ?
The 66 Sedan I removed the head from the Bolts where Very Tight lucky me I brought a Cheater Bar about 24 inches of aluminum Pipe I use for such
Head had next to No warpage *but the Head Bolts felt more like 100 Lbs of Torque and I have removed a Lot of heads , was worried I might Break a Head bolt.

[t walgamuth]

Stretch bolts can be measured at the neck to see if they are safe to reuse. I would have my machinist do it.

[Benz Dr.]

No stretch bolts on this engine so they can be used over and over again as long as there's no damage to any of them. Torque to proper specs and then undo each bolt one at a time and then re-torque to spec again. Do this after about 500 miles of diving with the engine slightly warm.
I use Permatex thread sealer on the ball stud base. Oil can and will leak by the threads. If you see oily spark plugs that's where it's coming from. Oil leaking out the exhaust will usually be burned in the manifolds so it can be harder to trace. If your plugs are clean it's a good bet that the exhaust ball stud/s are leaking if you see some smoke at idle.

[t walgamuth]

Originally Posted by Benz Dr.

Not stretch bolts on this engine so they can be used over and over again as long as there's no damage to any of them. Torque to proper specs and then undo each bolt one at a time and then re-torque to spec again. Do this after about 500 miles of diving with the engine slightly warm.
I use Permatex thread sealer on the ball stud base. Oil can and will leak by the threads. If you see oily spark plugs that's where it's coming from. Oil leaking out the exhaust will usually be burned in the manifolds so it canbe harder to trace. If your plugs are clean it's a good bet that the exhaust ball stud/s are leaking if you see some smoke at idle.

Here is what the op stated: Torque to yield ( TTY ) Bolts. Are there more than one set of bolts being discussed?

[Benz Dr.]

OP is wrong. Next.

[t walgamuth]

hah hah!