2 nd spark plug crushed...what happened?
#16
If the valve head dropped off first and then broke open a coolant passage, instead of hydraulic lock, wouldn't the coolant just get forced up the intake or out the exhaust? Depending, of course, as to which valve broke?
My guess is that the block developed a crack which leaked small amounts of coolant into the cylinder. The presence of this coolant messed with the normal heat cycles of the valve material inducing premature failure, the valve head banging around on the piston may have wedged in there on the upstroke and worsened the original crack. Good luck and good investigative work.
My guess is that the block developed a crack which leaked small amounts of coolant into the cylinder. The presence of this coolant messed with the normal heat cycles of the valve material inducing premature failure, the valve head banging around on the piston may have wedged in there on the upstroke and worsened the original crack. Good luck and good investigative work.
#17
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Maybe the valve retainer let go, allowing the valve to drop down, resulting the broken valve ? This is a pretty common failure mechanism on other engines if they're over reved. Not sure on the 944 series, but I suspect that it is. It's pretty common to replace the retainer during a rebuild.
-Bob P.
-Bob P.
#18
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The springs on the broken valve did not break. Looking at the liters they seem to be ine also. None are warped or scarred. The car has 159,000 miles on it. I'm still not exactly sure how the crack developed. About 2 yrs ago the engine did run hot for a few minutes due to a shift in the radiator, which in turn caused the fan to eat through the water pump hose. The water pump was recently replaced as were the belts and cogs. I loved this car and hate that this has happened. I'm not sue if I should part this one out or look for an engine. How much do used engines go for, and how difficult of a job is it to put in?
#20
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There's a guy parting out an 85.5 in Buffalo, NY (it's listed in the rennlist classifieds). He says that it's running fine. With the exception of a few external components, it should be a direct swap into your '83.
-Bob P.
EDIT : actually it's here -> <a href="http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic&f=24&t=000496" target="_blank">http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic&f=24&t=000496</a>
-Bob P.
EDIT : actually it's here -> <a href="http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic&f=24&t=000496" target="_blank">http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic&f=24&t=000496</a>