My civic hatch has a b18a turbocharged motor in it and i blew a head gasket. As i pulled the head off i found the tops of the pistons to have a thin layer of tar like substance on it, some i could wipe off and some i couldnt. Is this a sign of detonation? how can i clean this off / would i be better off replacing pistons (is this a sign of significant overheating)? Any input would be great!
Sounds like carbon buildup. Pretty normal.
how would you remove / clean it before putting it back together?
Soak a rag in gasoline and wipe them down. I wouldn’t worry too much about it.
Thanks!
detonation would be pitting?
if you are concerned with detonation, you should invest in/build some setup to monitor the engine.
a friend of mine uses a bosch sensor and a pair of headphones. you should be able to see the pics and the post.
http://www.turbo-mopar.com/forums/showpost.php?p=521051&postcount=50
another setup that works is here:
http://www.honda-tech.com/showthread.php?t=1555006
a little wierd looking but it will tell you if you actually have detonation or not.
Brian
leave the carbon on there, free thermal coating haha.
signs of detonation:
slivers of metal
pitting on pistons/valves/head
slivers of metal on plugs
or the more obvious signs
Thanks alot for the help!
My piston looks like the pic Toda posted…will Gasoline soaked rags take care of that, or should i JB weld it?
weld the pieces back on