value broken

[John H.]

I own 1972 SB Manual TM. Engine rebuilt 5 yrs ago,has 2000 miles on it.
As I was shifting from 2nd to 3rd normal driving. Engine started to make
metallic noise from valve cover.
After inspection by a different shop it was found that the STEM of the
valve had broken off. Also had one push rod that had split have way
down shaft, is now bent about 5 degrees.
I have been told that most valves are made in 2 peices. The upper tip
was machined together with the rest of the shaft. Apparently this tip
failed. Is there any other issues I should be concerned with.
Shop has sent off heads for new valves, push rods, lifters etc.

[Joe L.]

Re: value broken

I own 1972 SB Manual TM. Engine rebuilt 5 yrs ago,has 2000 miles on it.
As I was shifting from 2nd to 3rd normal driving. Engine started to make
metallic noise from valve cover.
After inspection by a different shop it was found that the STEM of the
valve had broken off. Also had one push rod that had split have way
down shaft, is now bent about 5 degrees.
I have been told that most valves are made in 2 peices. The upper tip
was machined together with the rest of the shaft. Apparently this tip
failed. Is there any other issues I should be concerned with.
Shop has sent off heads for new valves, push rods, lifters etc.

John------



Inasmuch as you've had two pieces installed at the previous "rebuild" fail with so little run time on the engine, I'd be VERY concerned about the quality of ALL the parts installed as part of that "rebuild".

[Duke W.]

Re: value broken

My bet is that the rebuilder filled your engine with a bunch of mismatched aftermarket hot rod parts, but I will be up to you to figure it out and decide what to do. Like Joe says, the whole valve train is suspect and maybe the rest of the engine.

I never recommend anything but OE equivalent valves, springs, rockers, balls, pushrods, and OE cam lobes. With enough head flow and an efficient exhaust system, SBs can run to 6500+ revs with hydraulic lifters and 7000+ with mechanical lifters, and failures are very rare.

Duke

[John H.]

Re: value broken

Thanks guys fpr your comments.
The original rebuild shop is a total joke....A MR.know it-all,
I found out the hard way.......Several thousands dollars later.
This shop had car in his shop for a heater core replacement
and the interior of car caught on fire.
Quote: "It wasnt't my fault, your radio shorted out".
I got to the bottom of his studity and NOW OUR NCRS CHAPTER
is having a judging clinic at his place in April.
What a wonderful relationship this appears to be.
I had to sue him in court.