Rocker Arm stud Question

[buzzkillg230rc]

HI All,
I had my heads rebuilt for my Porsche 2 liter. After receiving the heads I reassembled the engine. After re-assembly I ran the engine for 20 mins @ 2500 rpm to break in the heads, everything sounded great.
after a few days, I went to pull the car out and it started making a claking noise from the number 3 and 4 valve cover. come to find out my rocker arm stud on number 3 pulled from the head.
I took the head to the machine shop and had it repaired, it looks like they welded the area and tapped it with a helicoil. my question is, the rocker arm stud is not bottomed out, meaning i can tighten the stud, however if i tighten it all the way, it leaves me with no thread to attach my rocker assembly.
currently, I have them back out 1.5 turns out from bottoming out, which lets me get full thread on the rocker assembly. should i loc-tite the stud? or leave it as it?

Any info is appreciated

DeAngelo

[Clatter]

They make bigger studs for motors with big cams, etc.
Might look into a set of those - they use a bigger nut, and fit tighter to the rocker shaft.
Some are longer as well. Cheap insurance.

Short of that, I wouldn't hesitate to try a bit of Red Loc-Tite..

[buzzkillg230rc]

Thank you for the response. I called the machine shop and they recommended using red Loc-Tite.

[Type 4 Unleashed]

If they used a heli coil, then their shouldn't of needed to weld the head ? And for a rocker stud to pull it had to of been way way over torqued.

EMW carries the larger 8mm rocker studs, which are also longer for use with rocker base shims for room to set rocker geometry.

Most of the rocker stud holes can be seen on the bottom except maybe 2, so the rocker studs won't bottom out they will go thru the bottom side too far, making them too short.

[Piledriver]

The stock rocker studs the 7mm part should surely let go first, no?
The hd studs are recommended even on a stock rebuild.

[Type 4 Unleashed]

Before the 8mm stud upgrade, I never saw a pulled or broken stock rocker stud.

The larger 8mm upgrade allows for an increase in torque and better supports the rocker stands and the longer studs also allow for longer valves to increase installed height in springs for higher lift cams. I forget the torque on the stock rocker studs, 8 to 10 pds ?

The 7mm rocker studs, the stands, the adjusters, and the rockers are hardened steel, the rocker shafts are mild steel, who would of thought.

[wreck]

I used type 1 HD studs(EMW was out of stock of their studs) , I had to cut them down a bit . I needed the extra length because of the valve/spring set up . I've about 7mm of spacers . If using the type 1 studs you need to drill the rocker gear to fit the bigger studs .