JFK78

I recently had my D16Z6 rebuilt w/SRP pistons, eagle rods, blockguard, etc.
Break-in went fine, motor ran great for 2-3 months. Ran a max of 10 psi of boost.

So I went out after I had 1000 miles on it, turned up boost to 13 psi for the first time and made a run through 1st,2nd,and 3rd gears. No detonation, felt great. Let off in 3rd, shifted to 4th. All of a sudden motor is running on 3 cylinders and has a ticking/knocking noise. So I baby it home 2 blocks away and pop the hood, and start pulling plug wires while it's running to find which cylinder went bad. Cylinder #1 was dead, so I pulled the spark plug.

The ground strap was bent over onto the center electrode, and there was bits of aluminum spattered on the porcelain. Looking into the cylinder, I saw a scrape mark in the carbon on the top of the piston- something had obviously entered the cylinder and mashed the plug. So I put a new spark plug in and started her up.

She ran perfectly!! Except for the RPM dependent knocking/ticking noise, it seemed fine. I took it back out for a test run, and it ran perfectly, strong as ever. I did a compression test just to be sure, and all was well. I will never know what went through the cylinder for sure, but I have a theory I've settled on.

I think that a piece of aluminum from inside the intercooler came loose, flew through the charge piping and throttle body, and went through the intake manifold to the farthest cylinder (#1). It then entered the cylinder and contacted the piston and spark plug, bending the ground strap over, and then melted, thus the aluminum spatter on the porcelain. The plug has never had any aluminum spatter or flecks on it again.

So now it's running fine, but that noise is still there. It sounded like valvetrain, not deep enough to be rod knocking. I pulled the valve cover and checked out the cam and valvetrain like 3 times, and everything is fine.

So I drain the oil, and guess what? The oil is all metallic and silver looking in the pan, and I find pieces of metal in it, little curled up pieces that are aluminum on one side and brass/bronze on the other. CRAP! So I change the oil and filter, run it for like 20 minutes, and drain the oil again. Same exact thing as before. So I figure I've got a bad rod or main bearing since nothing else in the motor is made of that type of metal. Right? Wrong!!!

I drop the oil pan and pull all of the connecting rod and main bearings, and the thrust washer in the bottom end. Guess what- every single one is in perfect shape, just like they should be in a motor with only 1000 miles on it. Now I'm really confused. The pan has a ton of the metal shavings in it and lots of metal sludge. While under the car, the oil pump pickup tube was off, and I also noticed metal shavings just like those in the pan (that are way too big to fit through the pickup tube screen) are in the oil that is dripping out of the oil pump. What the heck?!?!?

I know that the block, head, oil pump, and oil pan were all thoroughly cleaned when I assembled the motor. And now I know that all of the bearings in the motor are fine, as well as the cam and valvetrain. Also the oil pressure readings are perfect, so I'm sure the oil pump is fine too in spite of the metal shavings I saw fall out of it. So I'm confused.

I am now confused, irritated and don't care. So I proceed to clean it all thoroughly, put it all back together, put new Redline oil and a new honda filter on it, and run it. I actually want it to break so I know what the problem is. So I proceed to turn the boost up to 15 psi and go to the track. The motor sounds nasty with the rattling/ticking/knocking sound, and I'm a little embarrased by it while in the staging lanes. I made 8 passes that night, and it was running stronger then ever!! No detonation or hesitation at all, running perfectly with 10-15 psi of boost (boost controller was fluctuating) and making consistent mid 12 sec passes at 111-115 mph!! And the noise never got any better or worse. I couldn't believe it!

So I go home, dump the oil, and yup, more metallic oil and shavings. I then put another new filter and new redline synthetic in it, and start her up. Oil pressure readings are perfect, spark plugs look great, running awesome. But knock is still there.

A few days later I go to another import race at bremerton raceway. I've got the boost holding perfectly at 15 psi. I make 5 passes, running low 12's at 115 mph. The car is running better than ever and I just set my new personal best time. On the 6th pass in the semi-final round, my tranny breaks on the shift to 3rd. I now have only 1st gear, nothing else, not even neutral. So I take it home and put her in the garage. I haven't touched the car for like 4 months now, but I'm now ready to get her going again. I've got a new tranny so that's solved. But this engine thing really sucks.

I really don't want to have to pull the motor out again, or remove the head. Does anyone have any idea what the noise is and where the metal is coming from?

The only other thing I didn't check was the the bronze piston pin bushings, but I have never heard of or seen these go bad. Plus the bushings are all bronze, not aluminum and brass/bronze like the shavings, and the amount of metal in the oil and the number of shavings was tremendous, too much to be just a pin bushing.

Any ideas anyone? Sorry for the long story, I just needed to get it out.

non-VTEC

i know you probably don't want to do this but i would pull the entire engine again and have it sent to the machine shop for close examination.

with all the metal shaving in the oil system you don't want it running through the turbo and stuff or one day it will grenade big time.

sounds like a valve train problem if the bearings are good...........maybe the cam is bad? or maybe a cylinder is so out of round and what your hearing is piston slap and the metal your seeing in the pan is metal from the piston/cylinder wall?

dunno what else to say........maybe pull the head and have someone come measure the pistons and cylinder walls.......

good luck

raene

After machine work was done, were all the oiling passages cleaned? If there was excess shavings in the passages that would explain where the metal shavings are coming from.

O16581724 5 2 5

I'm two years late getting in on this, but it sounds like your main bearings are the problem, if you didn't check those of course.

Pssst!

update please