all_motorsi

Take a look at these pictures of the #1 hole cylinder head.. all other combustion chambers are flawless, besides minor fuel deposits from running rich. The cylinder walls are beautiful and glossy, as well as all the pistons. tomorrow im going to pull the bottom end apart, as the engine was making a knocking sound during start up and high idle. I will update pics as the dismantle-ation continues.

Took this using an 8mp camera with the super duper macro setting

quicksilver1689

damn that looks bad, weird its only happening in one cylinder with it running rich. How does the corresponding piston look? prolly has little craters from where the metal was blasted off.

all_motorsi

actually, ALL of the pistons (including #1) are flawless!!!

thats why im posting this, beacuse if the piston was F***'ed and the sleeve was scored I would be shure that thats what it was.. but NO! this is the only damage on the entire engine for all that i can tell! I believe that the knocking/ tapping noise that i hear during start up and high Idle is probally this exhaust valve, im going to pull all the valves out and have a machine shop clean up the seats and head. But do you see the minor, bumply pitting texture all around the chamber... this is UNIQUE only to this hole. all the other head surfaces look smooth and beautiful WTF IS GOING ON PEOPLE>>>????

tricura

Is this a built motor?

BlueSi2k

hmm definitely looks like there was something foreign in there be it pieces of piston or something else. Maybe your motor ingested something somehow? Spark plug is ok?

96 GSR-T

my head looked like that after peices of JE's got all mashed up in there

HiProfile

Despite the valve seat soaking up heat, the cylinder head is generally cooler than the pistons, and you almost always see detonation on them first.

Are you 100% possitive that the head was flawless before you put it on last time? I could see being sold a built motor from someone not thinking you'd pop the head off that same day.

tricura

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HiProfile &raquo;</TD></TR><TR><TD CLASS="quote">Despite the valve seat soaking up heat, the cylinder head is generally cooler than the pistons, and you almost always see detonation on them first.

Are you 100% possitive that the head was flawless before you put it on last time? I could see being sold a built motor from someone not thinking you'd pop the head off that same day.</TD></TR></TABLE>
Kinda what I was thinking, if the head is torn up, but the pistons fine. They were put together that way. We've seen it here many times people bringing it to us, with some damage on the motor only to find out some hack threw it together and let it go.

JaredKaragen

is that a y8 head?

that looks like the aftermath of detonation... almost looks like the motor was assembled with the combustion chamber looking like that....

mike_belben@yahoo.com

looks like foreign object damage to me

HiProfile

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike_belben@yahoo.com &raquo;</TD></TR><TR><TD CLASS="quote">looks like foreign object damage to me</TD></TR></TABLE>

Exactly - when you've dealt with as many 40yr old CNC retrofits as I have, thats what the deck of huge machine looks like. The spots between the valves are clearly intended with raised ridges around the 'crater'. Detonation removes material, not displace it.

BTW looks like Z6 or B16 head, no flat quench zones.

mike_belben@yahoo.com

the dents are the giveaway. probably a spark plug strap broke off on a previous owner, head got sold apart from the piston with the matching tool marks.

detonation on a honda is more likely on cylinder 3 IMO

miller

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike_belben@yahoo.com &raquo;</TD></TR><TR><TD CLASS="quote"> probably a spark plug strap broke off
</TD></TR></TABLE>

I have seen this many many times, that is exactly what it looks like.