Some of you may remember, I've been looking around for a 455 that is not hurt too badly for core as a rebuild. I finally found one near enough that I could get it! It is a 1970 Toronado engine with E heads. That's the good news.

I started tearing it down this weekend and documenting each piece as I did so, just to be thorough. I pulled the valve covers on the passenger's side and found that the braces which link the intake to exhaust valve rockers are broken. Two of those braces are snapped, the ones over the #4 and #6 cylinders and both at pretty much the same spot.

Just to note, the engine turned over relatively easily (without plugs) before I disassembled the valve train. Looking at the cam and lifters for those cylinders, I see no other evidence of damage.

I am attaching two photos, but if anyone knows what may have caused this or has any diagnosis ideas, I'd appreciate hearing the diagnosis. Thanks!

Mark

 

No idea what could have happened, but I have some used bridges if needed.
Just pay the ship on 'em. Good luck with it.

 

That is not common, but not unheard of either. I wouldn't worry about it too much if you are rebuilding it anyway.

 

^^^This. It is not unheard of. Metal fatigue, manufacturing tolerances or defects, poorly done valve job that didn't set the stem heights properly, seized rocker arm on the trunnion - lots of potential causes. None of them are fatal.

 

Looks like the breaks are very clean indicating the engine has not been run much (if at all) since they happened. Suspect the person pulling the engine removed the valve covers so they wouldn't get damaged, and ended up damaging the rocker arm pivots instead.

 

I replaced the head gaskets on my Cutlass a while back and found two broken bridges as well. As long as they were assembled on the head lined up correctly it won't have any bad effects. Get a couple new/used ones when you put it back together and you should be fine. I found a couple at a wrecking yard for $2 each. They were in better shape than the ones I replaced.

 

Sure is a lot of sludge in that engine!

Gene

 

Get rid of those bridges and get screw in studs! Throw that factory junk out!