Carnage... Broken Rocker shafts... need some help

[TheCamel]

Well if some of you remember I posted about an issue with my motor, and I was not in the US when the motor began making noise when my father was taking it to storage.

The pictures below show it was not a blown motor, but instead broken rocker shafts, and if you can believe it, my father was able to keep the motor running on 3 cylinders for about 4 miles to get it to storage.

Few questions for the experts:

1) Are these the TA heavy duty shafts, or are they the stock units.
2) I know the shafts are prone to breaking from reading the posts on here, but to the bolts usually snap off as well?

As you can see from the pictures the pushrods are not in the correct positions, and they are not seating into lifters. I am wondering if they may have pushed out of the block and are sitting in the intake valley (will pull the intake later this week, just wonder if it is possible.

The cam is a Lunatti 200/200 and I was not sure if I want to replace it now as well. Once I get the intake off and see how bad the lifters are, I may go with the heads and cam, or if there is glitter in the oil filter, then I may be calling Don Cruz to see if he can work some magic...


Thoughts?

 

[Rafs-T-Type]

I recommend the TA shafts, stud it, and use rjc caps. I bet the bolt broke and took the shaft with it.

 

[Amelio]

been there done that I got several broken shafts......

I am upgrading mine as we speak....I got the solid shafts and the RJC braces as well as the stud kit from TA.....this should fix the issue.

Hopefully those broken bolts dont give you too much of a fight.....good luck!

 

[earlbrown]

I've never seen one break in the middle. Normally it's the outside one and the rocker shaft peels up on the end. I almost wonder if the hold down bolts weren't properly torqued and they backed off just enough to let harmonics start wreaking havoc until everything started breaking. Those rocker buttons look almost new.

A magnet will pop those countersunk pushrods right out. Make sure to check them all for straightness before thinking about putting them back in service.

The rocker saddles are a needed addition on any engine from stock all the way up to hi po.

 

[750H.P.V6]

I agree with Earl that the shaft breaking in the middle isn't anything I've seen before. I was trying to see if there is evidence of fretting between the rocker shaft and the saddle which could be evidence that the bolts were loose and the shaft was moving around. Having all 3 bolts break is really strange, I suspect one of the end bolts failed first prior to the shaft breaking in the middle. How long had it been running after the cam install before this happened?

Neal

 

[bryesh]

Look at the middle bolt where the shaft snapped. It looks to me like there are clear striations, if so a crack grew at this bolt and it snapped. Without the bolt holding it, the shaft was overloaded in bending and broke right at the weakest point, the bolt hole. After the shaft snaped in two, loads from the rockers would have pryed the two shaft halves up on the remaining two bolts, snapping them. To me it doesn't look like the shaft or the other two bolts have striations, if not then they probably weren't fatigue failures. I bet those are some stiff springs too... .Just a theory.


Also I don't remember my stock rocker shaft being that thick. Am I wrong or is that an aftermarket shaft?

 

[Boost231]

I ran ta performance shafts with Rjc.braces. Next thing I broke was the rocker itself. Will snap at the base. In the end its just better to go with roller rockers. High spring pressures will break all kinds of parts. One weak link at a time

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[jasjamz]

I ran ta performance shafts with Rjc.braces. Next thing I broke was the rocker itself. Will snap at the base. In the end its just better to go with roller rockers. High spring pressures will break all kinds of parts. One weak link at a time

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True. But his heads would need to come off to trim the pedestals. At that point, best to put some ported ones back on.

 

[baby6]

Wow never seen that happen before. Crazy

 

[Rafs-T-Type]

My solid shafts also broke in the middle - http://www.turbobuick.com/forums/threads/pics-of-broken-rocker-shaft.329335/. There is also a link to a "how to" ditch those buttons. Those buttons really messed my day up..I should say days . Check it out!

 

[ZNix]

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[coldair85GN]

I've broken 2 stock GM rocker shafts back when my car was a hotair but never broke the bolts. I'm using Harland Sharpe 1.65 roller rockers with the heavy duty braces they came with now. I can't imagine those breaking.