Rocker studs coming out?

[69gmc-IN]

So I've been working on getting my GMC back road ready, was trying to diagnose a clack that to me sounded like a rocker arm slapping a valve. I'm a novice here so this was just my first guess and what I thought would be easiest to check. well I pulled the valve cover today and found that most of the valves had some lash in them and a couple were excessive. I went to tighten the rockers down and remove the lash when I found that one wouldn't tighten any more. Then I noticed it the stud is much higher than the rest so I started looking closer and I've got a few studs that aren't level with the rest. It seems that the rocker studs are backing out. What am I looking at to get these replaced? I read some older threads on here that said you can't really press them back in cause they'll just back right out again. Any estimate on how much it would cost to have a machine shop replace all the studs with screw ins? And if I do would this be the best time to replace/clean/refurbish/whatever the valves? I don't have a ton of money to dump into it right now. About 8 years ago I had a stuck thermostat and the engine temp got pretty high, but if I remember right it didn't get super high before I shut it down. Also any other general thoughts about the condition of everything seen in these pics I'm really trying to learn all I can and do things right. Also I'm seriously considering replacing all of the lifters since they're probably original.

Pics below. Thanks!

[GRX]

It does indeed look like your studs are pulling out. Three solutions. All of which I have performed at one time or another.

#1 - simplest is to drive them back down and pin them. Which involves drilling through the stud boss and the stud, then driving in a roll pin. You can buy a drill bit and set of pins for $10. Have to be careful not to mushroom the top of the stud of course. They used to make a special tool which drove on the center of the stud top when you hammer them down. Have not seen one in a while. You can also thread on a couple old rocker nuts and hammer on those.

#2 - next is to buy a stud puller, tap the holes, and install a set of straight double thread studs with no hex. Then reinstall your rocker components.

#3 - best option is to pull the heads, have a shop pull the studs, have them tap the holes and machine the top of the bosses down for studs with a hex. This is a good time to have them round out the push rods holes and install some guide plates. And yes.That is the best time to have them thoroughly checked over. Guides, flatness, seat wear, etc ...

[69gmc-IN]

Ok, so option #3. any idea on a ballpark range for a shop to pull the studs etc? how much to have the head once overed? I've never done any of this before so I have no clue if it's a $100 or a $500 job.

[hugger6933]

Call your local machine shop and ask them the price to do screw in studs for a 6 cylinder.

[69gmc-IN]

Sounds good. I just got the number of a local shop that's supposed to be pretty good. I'll give them a call tomorrow and get an estimate. Thanks for your help. I'll try and keep this thread updated.

[hamjet]

Pulling studs isn't hard, just stack a bunch of washers and tighten the nut. I did that and then threaded the hole and installed a screw in stud with out the hex. the head was off the block, but I've heard a lot of people doing it on the engine. just use rags or tape or what have you to stop thread shavings from falling in the engine. plus I used high strength thread lock on the stud..

[kwmech]

Do the 6cyl studs go into the coolant jacket like the small blocks, may want to drain a little before doing it in the vehicle

[69gmc-IN]

OK I've been busy for awhile but planning finally starting to work on this truck again. Does anyone know the answer to the last post in this thread? do the studs go into the coolant jacket or not? I'm assuming if they do it would be less than ideal to tap the head on the truck, wouldn't that risk putting shavings into the coolant system? Thanks again everyone in advance.

[GASoline71]

Originally Posted by GRX

It does indeed look like your studs are pulling out. Three solutions. All of which I have performed at one time or another.

#1 - simplest is to drive them back down and pin them. Which involves drilling through the stud boss and the stud, then driving in a roll pin. You can buy a drill bit and set of pins for $10. Have to be careful not to mushroom the top of the stud of course. They used to make a special tool which drove on the center of the stud top when you hammer them down. Have not seen one in a while. You can also thread on a couple old rocker nuts and hammer on those.

#2 - next is to buy a stud puller, tap the holes, and install a set of straight double thread studs with no hex. Then reinstall your rocker components.

#3 - best option is to pull the heads, have a shop pull the studs, have them tap the holes and machine the top of the bosses down for studs with a hex. This is a good time to have them round out the push rods holes and install some guide plates. And yes.That is the best time to have them thoroughly checked over. Guides, flatness, seat wear, etc ...

I have done option #1 many times. Even while the heads are still on the engine in the truck. I have put a nut on the stud and used a brass hammer to tap down the studs.

Use a shop vac to suck up the metal shavings when you drill and also stick rags in the drain back holes just in case.

The rocker studs do not go into any water jackets on SBC heads that I am aware of. The lower head bolts along the bottom of the outside of the heads do.

Gary

[69gmc-IN]

Awesome thanks for the reply. I'm pretty sure I'm going to re seat them and drill/pin them on the truck. I think it's going to be the quickest fix for me to get the truck back on the road.

[GASoline71]

It is quick, and on the I-6 head there is a lot of room to work and a pretty decent sized area to drill into.

Gary

[geezer#99]

You don't even need to drill and pin them.
Just Stake them in place.
Use a solid pointed drift or punch and punch them right where the stud and boss meet. Do it at a 45 degree angle.
One on each side will work.

[RichardJ]

I don't know if I'd trust staking the studs. Stock valve springs have dampers which I can't see in your photos?

These pictures are from Leo Santucci's Inline Six Book.
The second picture shows drilled guide holes, threaded stud holes, knurled guides and hole for A.I.R smog tubes.
Stud holes are open to the water jacket.

[mmiddle]

^^^^ Pictures win the day and settle the debate.
Drill 1/8" hole and drive roll pins in there. As long as you are running a stock cam there should not be any issues with studs lifting after they are pinned. This is actually a common problem.