<VV> '69 140 head issues

[Tony Underwood]

Some may remember me bitching last year about the blue '69 suddenly 
making clacking noises hammering like it had rocks in the 
chambers.   This, after I'd taken hard notes about a suggestion made 
regarding pinning the seats with set screws... gave it a shot and had 
success, car was running well and I thought it was done.

Then came the clanking and clattering and I went "damn", after all 
that set-screw work pinning the seats and ANOTHER one came out???

I said bad words.   Parked it until I could get to it...


After a year, I Finally got to it... head came off 
uneventfully.   OK, here's the cool part.



ALL the seats were intact and in place, although one was all polished 
up and almost "funnel shaped" and the valve was "sunk" down into the 
seat.   The pistons on that side had shrapnel embedded in the crowns, 
all three.   I was puzzled, no idea what the HELL could have gotten 
into the cylinders... until I looked closer at the valve springs, 
particularly the one with the polished seat and sunk valve.


The retainer and spring could be wobbled easily by hand.   I mean 
WOBBLE.   The guide was gone.   Missing.  Vanished.   Or rather 
transformed into shrapnel.   Intake, #4, everything else seemed ok.


This head had been to a reputable (I thought) shop to have a seat and 
two guides replaced, I got guides from lclc and the seat was a stock 
item the shop had on hand.   I then picked up the repaired head and 
pinned the seats as per the suggestion that had been posted on 
VV.    Seems the guide in question ( the MIA guide) was one of the 
guides I had the shop replace.


So:   I had been condemning the pinning method concerning the 
seats... but that wasn't the problem this time, it was the shattered 
guide that simply slid down into the port and broke up.   No 
fragments anywhere in the head around the spring or rockers etc, not 
a trace.   Everything was all in the chambers and embedded in the 
pistons on the driver side.



This was the first time I ever saw a guide simply fall out and get 
crunched by first the valve then the piston(s).    I'm gonna be 
checking the pistons close before I start in on putting things back 
together.   I've seen pistons that busted seats and survive with 
simple scars, but this thing was really hammering when she brought it 
back home that last time.   And, what didn't stick in the pistons 
stuck in the squish area of the head.


I'll probably have some fun with this one before it's all back 
together again.



tony..