Car was an '02 Maxima with 6 speed trans with just an intake. This engine had about 200K miles on it and was consuming a quart of oil every 200~300 miles. The precats and main cat converter were blown out and the engine knocked/pinged non stop when it got to operating temp then it would died at idle.

I removed it and swapped it out for an '06 VQ35 about a year ago.

I finally got around to tearing down the motor tonight to make room in the garage and sell off the scrap metal. Don't normally take alot of pics but when I pulled the cylinder heads off I was like



Cylinders 2, 4, 6 from left to right.



Cylinders 5, 3, 1 from left to right. Cylinder 5 is caked with several mm of carbon/burnt oil.



Cylinder head for Cylinders 5, 3, 1 - Look at the damage caused on the exhaust valves!!!



Cylinder head for Cylinders 6, 4, 2



Cylinder 5 up close.

The head gaskets finally went with all the crap in the combustion chamber and there was oil & sludge in the coolant. The timing covers and about every else was caked in nasty black sludge. Surprisingly bearings in the crank and rods were OK for the damage to the engine.

 

very nice

 

Where you been at?

 

just finished up school, now im free lookin for a job

 

I don't think the tops of the pistons themselves look all that bad. If you take the heads off of pretty much any engine and it will look like that. It's nothing that a little seafoam wouldn't clean up.

You'd get more insight by looking at the cylinder walls and ring lands.

I would have bored out this engine and put oversize HR pistons in it as long as the heads and crank were in good shape.

 

I agree, that is not terrible. I have actually come across cases where the motor didnt even turn from so much carbon buildup, we couldnt figure out why it would stop turning, even with a long a$$ breaker bar, turned out to be the carbon hitting against the head.

 

I can vouch for that

 

Haha seafoam won't touch this stuff, brake cleaner and a brush maybe.

Cylinder walls are scuffed up and rings are pretty ratty.

I've pulled a few VQ engines apart and this is the worst I've seen by far. Carbon build up on cylinder #5 is always there with every FWD VQ but this is the most I have seen.

Carbon build up didn't stop the engine from spinning that would be pretty intense if that was the case. It did start to get into the coolant from the head gaskets.

This motor was torn down to parts for scrap, it won't be rebuilt.

 

I've torn down a VQ35 with 800 miles on it and the pistons looked like cylinders 3 and 4 in your pictures.

 

Same thing happened to me with the vq30 I have apart right now. I thought I had a bent valve so I was pretty happy when I took off the head to find a small piece of carbon caught between the piston and head.

I agree with the point made about the rings as well. The engine I tore down has this thick sticky disguestingness slathered in the ring grooves. The small oil passeges through the back of the the piston where excess oil from the oil rings drains back into the crankcase were almost completely plugged.

 

god damn!

 

I've been searching for a how to on replacing the oil rings, and this thread came across, and since it's relatively recent, and all of you that replied seem to have seen the inside of a cylinder I thought maybe I would ask in here if there is any how to out there on getting those rings replaced, I got a 2002 6speed, and I would say it burns a full quart in 200-300 miles. Sad thing is, it's only got about 75k miles, so I would like to take it apart and replace the rings. But the most I've ever done was to replace a clutch so I never got that deep into an engine before. Any advice, links, ideas would be great. Thanks.

 

Curious on how much you think you would get money wise for the scrap metal?

 

It's not for the faint of heart. I wouldn't do it alone if all you've ever done is a clutch. The could be more wrong than the rings. You could have a broken ring land(s) on the piston. You should have worn cylinder walls. If you want to do it right, you'd bore it out, matched to the new pistons, preferably HR pistons.

Or you could go the easy route and pick up a newer engine from a junkyard for almost nothing. Put in an 08+ altima/maxima engine, for instance.

How's your compression? Have you done a leak-down test? There are other causes of excessive oil consumption besides rings.

 

It would be worth more selling for parts. Personally I would have honed and re-ringed it, unless there was deep cyl scoring. Seems scrapping the parts would be a disservice to you and the maxi community. FWIW I think scrap prices are at a low right now.

Sea foam on hot carbon in a running motor would have broken that up and give you more life. Nothing short of rings would help the oil burning though.

 

Bro, that's probably how my engine looks. I have a 2002 altima 5mt, alot of mods, with the VQ and i burn a quart of oil a freaking week. About 200-300 miles a quart..it is sooooooo frustrating. Especially when you have a father that thinks there isn't anything wrong with your car.....