broken rocker stud

[walkerheaders]

hi guys,
please help, I need to know if i can replace a rocker arm stud while on the car? and where i can get one? and if coolant will come out? i have 690 heads with stock 3/8 pinned studs.

i just got back from my 4th drive across america since july. (company truck and trailer)
i decide to treat myself today with a drive to work in the impala. about a mile from work, i hear noise, unusual noise, popping back thru the carbs. WTHell? i start pulling plug wires till it changes and decide #8 exhaust is not opening. i have to drive it home, no real choice. and luckily no real problem.
TURNS OUT: the roller rockers sit higher than the stockers and there are not alot of threads holding the poly lock. the top of the stud broke off. looks like i will have to put the stock rockers back on for now. the rollers didnt cure the noise i was having anyway. this isky 296 hyd. runs good but is not quiet? i have had the rockers down from a 1/4 to 1-1/2 turns in increments, no difference.
hope somebody has a good idea.
if the head has to come off, then it will get a set of screw in studs, BB rods, a big solid cam, re-sealed and re-balanced. just didnt want all that me$$ right now.

PS: you all know i am pullin for our man Fred, just havent been here to say.

thanx for your help on this, i like my 409 better when i can drive it.

[johnnyrod]

I like drivin the car as well. I dont know much about water jacket and studs but if it is a problem just drain some fluid off like lower the level and give her. Not much to lose if you do find water at least you could move ahea:cool: d and be back driving real soon. Good luck John

[RCE1962]

Walkerheaders

Well...I went through all of the highschool auto-mechanics years and completed a whole bunch of hours towards my mechanic's license...then life went sideways.... and... that door closed. Still love it though....... and lots to learn.

Anyways, I can't offer as much technical advice, as most... if not all...the members on this forum, but I like to think I can keep up in some respects. However, in terms of "technical" I think, presenting my advise to you... and many others here, would be like preaching to the choir. Having said that...I'd still like to offer my "observed" opinion, since i stongly beliveve there is relevance.

I bought a set of 690's about 1½ years ago. Both cast in 1961. One head has a cracked rocker stud. Hope to install re-worked heads in 2007. I've talked to many auto-enthusiasts, hot-rodders, restorers, etc, down here, and have also presented my case here, on this forum. Summary of inquiries include, high spring pressure, slight casting imperfections, pin and drilled pin areas, and just plain old age & stress, may contribute all or just part of this problem. I can relate to age and stress... BTW.... but will refrain from any close references to the noted sub-title at this time.

These 409 heads have become increasingly rare and expen$ive heads.... that apparently can have a bit of a weak link in the rocker-stud area. Afterall...the engine is 41-45 years old!!! Everyday use will compound problems.

Personally....before I install these 690 heads, I will get the screw-in studs done. I've debated to preserve the original status of these heads...but at the end of the day...I like to drive the car, as well as, and to continue its overall life & protect the investment. (Sorry..no candy-*** stories). Standing on it..from time to time..should not be an issue).

Knowing what I know now, even if I was looking for a 409 car today...I think I'd prefer the insurance of the screw-in studs, even over original. I can a appreciate a "survivor' as much as the rest of you, but I hate to think of this, or the rest of the 409 motor market as a "Historical Powerhouse" but yet similar to a "boxer with a glass jaw". (Bad example...but you get the idea.) Probably getting pretty darn close to the collector market expecting these to be replaced anyways.

I'd consider it a bonus if it was already done. But that's just my opinion. :)

RCE1962

[fatride]

Bob, I had the same thing happen to me. In my case I already had Mr Gasket screw in studs installed. As far as replacing the stud, since it is a press fit it would be a good iodea to heat the head a bit and place the stud in the freezer. Lineing the stud hole with the hole in the stud boss could be a problem. I'm sure this job can be done at home. Also, Mr Gasket makes a screw in stud that does not require milling the stud boss. I have a number of the studs here and will send you what you need. The stud has a shoulder and can be tourqed by double nutting Coolant should not be an issue although the stud does hit water. I'm uninformed enough that I would try this if it were my engine! If it doesn't work you can always pull the heads. :stooges

[bluescreamer]

Bob
I would try replacing stud. 1st you will hit water when you pull stud.
Drain water
2. valve spring has to come off so you can drive roll pin out toward
valve stem. may have to bend pin to remove it.
Not much room to use a drift pin and a hammer because you are at the
back of intake. there are worst locations with a lot less room.
Hope there are enough threads remaining on stud so you can force
the stud out of head by shiming under nut as you turn it down.
I did this a number of years ago when I broke a stud. only problem
I can see is when you replace the stud and have to aline it with the
hole in the stud boss. I used two small nails the same size as pin
and positioned in the stud and one in the stud boss. Then
eye balled the alinement and tap the stud down in to position.
Take hood off car it gives you more room to work with. Take your time
it can be done.
Allen

[CDNpontiac409guy]

Bob, I have no explanation for the valve train noise...
but stud relacement....
like Allen said:deal :deal :brow

[dq409]

the rollers didnt cure the noise i was having anyway. this isky 296 hyd. runs good but is not quiet? .

I think you replaced one noise with another.
There are many discussions here about the roller rocked noise as this is common with the rollers.

I didn`t notice any rocker noise before it was mentioned here as I always thought it was normal but they do make noise I call music !!!

I would pull the heads and replace the pinned studs with screw in ones,,, jmo

[skipxt4]

Bob: The info that Fatride and Bluescreamer gave you is right on the money. Boy, you can't get any more unlucky than that, breaking the last stud on the engine.:mad: It couldn't have been number 4. Of course not, that would have been too easy. Anyway, if you get your pinned studs from Showcars, they are .003 larger on the bottom. You will definately have to heat the stud boss and freeze the stud, before installing it. I have used dry ice in the past, with good results, but be careful and protect your hands and face. Skip :)

[bluescreamer]

Bob
I would be careful with a over sized stud. I would use a standard Dia,
stud, You have the replacement roll pin holding it place after its installed.
Run the risk of spliting stud boss, with a oversized stud, unless you
have reamers to oversize hole.
When I did this I used a mirror and light to aline hole as I was
tapping stud back into its final position.
Allen

[skipxt4]

Bob
I would be careful with a over sized stud. I would use a standard Dia,
stud, You have the replacement roll pin holding it place after its installed.
Run the risk of spliting stud boss, with a oversized stud, unless you
have reamers to oversize hole.
When I did this I used a mirror and light to aline hole as I was
tapping stud back into its final position.
Allen
When the original stud is removed, the hole becomes enlarged making the use of OS studs necessary. .003 is the thickness of a sheet of paper. Skip:)

[walkerheaders]

thanx so much for the replies. looks like i may get a chance on sunday to look it over and decide what to do.
the last time this car broke a rocker stud, it was 12 years before i drove it again. we dont want that to happen.

[walkerheaders]

glad i didnt have to take the stud out. (looks like a major PITA)
thanx again for all your help.
finally got to have a good look. it broke only about 3/16 off the top! very strange but good for me. the roller rockers just dont grab enough threads without screw-in studs.
I was able to run a die down the stud just far enough to sand the top of the stud flat. then i machined an extra set of poly-locks to get maximum thread contact. put the stock rockers back on and away we went. the 409 seems happy for now. I still have some ticking noise that wont go away, people just think it has solid lifters and i just leave it at that. in the future, i will go with solid lifters, 7/16 screw in studs, rat motor rods, and a reseal and re-balance job. for now, it's all good.

PS: i now have a nice set of purple Angus 1.75 3/8 stud rollers for sale cheap.

[BA-Man61]

Bob,

I'm glad your 409 is back in action! I've admired you car several times at some of the local cruise-ins, and I have to tell you that is one beautiful machine. Anyway, I might be interested in your rocker arms, and I'm only about 35-40 minutes away (near Wolfsville). I've just finished a 348 for my 61 BelAir, and I aquired two 409's last year. I'm planning on building a stroker for my 63 SS. I hate to turn down "cheap" parts. Send me an email if your intereted in selling them.

Thanks,
Eric

[walkerheaders]

thanx for the compliments eric. sometime step up and intro yourself. although i do try to avoid being near the car when it's on display. gonna be around the next few days. home 301-898-5678 cell 410-259-0581 come on over. 2 miles east of libertytown on rt.26