RB26240Z Posted February 15, 2011 Share Posted February 15, 2011 (edited) The car has a stock bottom end. N1 oil and water pump, metal H/G, single turbo - gt4088r. The car was being tuned at shop. During the first run, I heard metal noise (sort of broken metal pieces in a can)around the valve cover,tuner shut the car off immediately, I took the valve cover off did not see anything. Decided to tear it down to avoid further damage. Brought the car home, engine out and head removed, I noticed metal debris inside the headers when removing it. Turbo spins fine nothing in there. When I removed the head, here is what I found. Pretty much on every cylinder, more on 2,3,4,5. anyone seen this before? Edited February 15, 2011 by RB26240Z Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted February 15, 2011 Share Posted February 15, 2011 Yep... that's called MAJOR detonation... Same thing on this first 26 I bought. I got another one to use. Quote Link to comment Share on other sites More sharing options...
RB26240Z Posted February 16, 2011 Author Share Posted February 16, 2011 Thanks for the reply. Is the head reusable? Quote Link to comment Share on other sites More sharing options...
johnc Posted February 16, 2011 Share Posted February 16, 2011 It kinda looks like something got into the combustion chambers, but there are no marks on the valves. Would detonation chip little chunks off the quench areas and then toss them around in the engine? Quote Link to comment Share on other sites More sharing options...
jeffer949 Posted February 16, 2011 Share Posted February 16, 2011 Im going to have to say that is FOD (foreign object damage). The marks are to square edged to be detonation. Detonation is pretty much always domed in shape. Also the fact that you had stuff in the exhaust points to something being in the cylinders. Had you had intercooler piping welded up and some slag could of broken off and gotten into the cylinders? Or are you running an open intake on the turbo that you could of sucked something in?? Just my experience. Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted February 16, 2011 Share Posted February 16, 2011 I'm 100% positive it's detonation. Quote Link to comment Share on other sites More sharing options...
kiwi303 Posted February 16, 2011 Share Posted February 16, 2011 looks rectangular/triangular dents hammered into the surfaces, very much like the inside of the chamber and top of the piston on a Sthil FS450 brushcutter that lost it's ring and had a piece bounce around the combustion chamber. Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 16, 2011 Share Posted February 16, 2011 How about a picture of the debris from the header? Quote Link to comment Share on other sites More sharing options...
tyler031734 Posted February 16, 2011 Share Posted February 16, 2011 I'm 100% positive it's detonation. I'm 100% positive its foreign debris... There now were even. But what the heck got in all the cylinders plus in the header and not take chunks from the turbo? Got a muffler? Check it maybe? Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted February 16, 2011 Share Posted February 16, 2011 I'm 100% positive it's detonation. OK, maybe I should have said "caused" by detonation......... I still believe it's detonation the OP/tuner heard,, and was the cause of the damage shown to that head. I can assure you the ring lands are collapsed to some degree on at least one of those pistons. Edit: After looking at the pics enlarged, it appears to be pieces of valve guides, and ring lands / rings scattered around the chambers. Post those pics up on the Australia RB sites and see what they have to offer. I'm sure that is a image that has been seen often. Quote Link to comment Share on other sites More sharing options...
jakeoster Posted February 16, 2011 Share Posted February 16, 2011 Damn tough luck man. You just recently get her running? Quote Link to comment Share on other sites More sharing options...
RB26240Z Posted February 16, 2011 Author Share Posted February 16, 2011 Yes, I did get her running recently (January), and yes, that's pretty much what I've been having is tough luck with this thing. It's been almost 9 years and I am pretty sick of it already. If its not one thing it's the other. I spent waaaaay too much money on it to just get rid of it, and can't find the motivation to go forward and do a complete rebuilt. Quote Link to comment Share on other sites More sharing options...
RB26240Z Posted February 17, 2011 Author Share Posted February 17, 2011 Upon further inspection and clean up, I got some samples of the pieces on the pistons and the head. (1st photo) They are aluminum, and looks like they are pieces of the head/quench area, and the pistons. Here are some photos of parts taken off, (to go back on, soon, hopefully). Quote Link to comment Share on other sites More sharing options...
RS Speed Posted February 17, 2011 Share Posted February 17, 2011 checked to see if all the valve guides are in place... ive seen them crack and drop a piece off into the head. Quote Link to comment Share on other sites More sharing options...
jakeoster Posted February 18, 2011 Share Posted February 18, 2011 Yes, I did get her running recently (January), and yes, that's pretty much what I've been having is tough luck with this thing. It's been almost 9 years and I am pretty sick of it already. If its not one thing it's the other. I spent waaaaay too much money on it to just get rid of it, and can't find the motivation to go forward and do a complete rebuilt. I felt the same way after my build was trashed by a negligent driver after driving it about as many times as you can count on one hand. It'll work out man, just take a little break from it for a while. Quote Link to comment Share on other sites More sharing options...
ZT-R Posted February 19, 2011 Share Posted February 19, 2011 sorry to see that man, that blows. Quote Link to comment Share on other sites More sharing options...
synthtk Posted March 3, 2011 Share Posted March 3, 2011 Looks like my head after I melted piston #2, head should still be usable, just take it to a machine shop and have it checked out to see if i can be milled down. Quote Link to comment Share on other sites More sharing options...
MONGO510 Posted March 3, 2011 Share Posted March 3, 2011 Foreign object went thru engine. You would have chunks of piston missing if those pieces were from detonation. Material can go thru the turbo. My $.02 Mongo Quote Link to comment Share on other sites More sharing options...
Mark N Posted March 11, 2011 Share Posted March 11, 2011 I would have to agree with the detonation diagnosis. What sort of fuel system are you running and what AFR's were you reading at the time it happened? Quote Link to comment Share on other sites More sharing options...
frank280zx Posted March 11, 2011 Share Posted March 11, 2011 I agree with the detonation analsys Remember detonation is an erratic form of combustion that apart from causing head gasket failure also is wel capableof causing other engine damage. Detonation occurs when excessive heat and pressure in the combustion chamber cause the air/fuel mixture to autoignite. This produces multiple flame fronts within the combustion chamber instead of a single flame kernel. When these multiple flames collide, they do so with explosive force that produces a sudden rise in cylinder pressure accompanied by a sharp metallic pinging or knocking noise. The hammer-like shock waves created by detonation subject the head gasket, piston, rings, spark plug and rod bearings to severe overloading. And yes the pictures shown look allot like sever detonation.. and it is consistent with the sound heard (metal knocking) Not FOD 9 though the pieces knocked of by the detonation might cause "FOD" but sure as hell this is caused by leaning out big time. Sorry to see it.. but that one will need a complete rebuild (check your bearings aswel) Quote Link to comment Share on other sites More sharing options...
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