Are you sure that you are not having a “spring bind “ situation? Also take a look at some of the other rocker arms to make sure they are not hitting the studs at maximum lift. You may have to use a different set of rocker arms.
Hi Rick..... I did change that cam and rocker arms during the rebuild .
I used the Comp Cam XM270HR has about 0.500 lift and installed 1.5 Roller Rockers .Springs were also changed to accommodate the cam .
Now I'm done for the season.
I believe I have yet another rocker arm stud problem! After the last broken stud I removed the roller rockers and went back to the stamped rockers thinking the ny-lock bolts were not engaging the stud well enough. Well I don't think that is/was the case. Had another issue this w/e and after putting the vac gauge on it looks like the same problem.
Not even going to check it........just gonna pull the boat and address it over the winter.....have screw-in studs installed!
I guess it's true what they say about the press in studs........they $UCK!
Even with the oem studs pressed in you should not be breaking them Take the cam lift multiplied by the rocker arm ratio and figure out how much the rocker arm moves. Remove a valve spring and compress it fully measure its height.
If rocker arm travel is more than the spring height thats why the studs are breaking
Before you remove anyhing measure the spring with the valve fully open. guessing you wont fit a business card between the coils
NOT TO SCALE
If the ratio moves the rocker arm tip 3 inches and the valve spring compressed is 3 -1/2 you break the stud.
If the ratio moves the rocker arm tip 3 inches and the valve spring compressed is 2 -1/2 inches your fine
Very interesting test! Will look at that before I take anything apart!
Also thanks for the link.
Hoping to pull the boat this w/e..........not even going to change the oil......do it in the spring; not in the mood!
Just gonna power wash; remove the OD; drain the raw water side and cover it.
They're good heads but can only handle .420 lift. . What will your machine shop charge for screw in studs, cut guides and spring pockets ? Or run a smaller cam
