No Vaccum after breaking rocker shaft bolt

[sdteb]

So after blowing a HG and putting 'new heads' on it that were ported and valve job with big valves, started the car up every thing was great. driving her around and literally a rocker shaft bolt on the front driver side... replaced it with grade 8 bolts started back up, hard to start and sounded like i didnt tighten them down correctly, very luggish response, so I order ARP rockers bolts and put it back together, very hard to start and as literally 3-4 in vaccum....wTF???? before the rocker shaft bolt broke it was so smooth, i cannot find a vacuum leak ANYWHERE

help

 

[salvageV6]

Did you do a compression or leak-down test yet?

Another test would be to pull the valve cover off the side with the broken bolt and have a look while it's idling.

 

[Pronto]

Sounds like it might have bent a valve.

 

[sdteb]

pulling the heads back off , sucks,,,,,no compression on the cylinder where the rocker shaft blot broke. bent valve? hole in piston? ill have it off asap worked on it today

 

[sdteb]

ok so i pulled the head off when i could not get any compression on number 1 cylinder.... 3 had some compression and i gave up aftr that,.... when putting 'new' different set of iron heads and new big valves in it with new valve springs should i have had to measure for new pushrods? this is a roller cam engine... remember after about 10 miles it broke a rocker shaft bolt and then ran like this...
ill post before p vids of it running fine at start up and pics of the head and piston today.. i poured alky in the valves and not leaking ..

the original pushrods are 8.250 in length....080, could this be the culprit?

 

[Chuck Leeper]

when putting 'new' different set of iron heads and new big valves in it with new valve springs should i have had to measure for new pushrods?

Most certainly.
My guess is, you coil bound some springs, and subsequently, found the weak link in the shaft.
Lay a strait edge across the tips of the valves. Big differences in installed height?

 

[earlbrown]

Pull your pushrods and see if one of them got bent during the shaft failure.

 

[sdteb]

no bent pushrods... it would be awesome if someone have a good youtube video on verifying pushrod length on buick v6... to double check my work, yes, its my first time measuring these.... even though i have couple of these.