My timing chain install went very wrong. The exhaust cam 24mm hex built into the cam to hold it still rounded off. The exhaust sprocket is permanently stuck to both exhaust cams. I was using my 1" impact and needless to say the cam hex head gave before the the exhaust cam sprocke bolt. I spun the cam around before i could pull the socket off and broke the #1 exhaust valve in half. Great now add another 8 hours to remove the engine due to how hard the the transmission bolts are to get. Along with the passenger side manifold to convertor connection, it was not an easy task. Well i get the engine out and flex plate off and get the engine mounted to the stand. Here i start finding problems. i find black exhaust soot around the back of the block starting from the back rear portion of the exhaust manifold. no cracks so im guessing bad gasket. Leaking rear main seal. severely torn motor mounts. and the drivers side catalytic converter has what looks like a perfect ice cream scoop out of the center of the catalyst. All 6 soark plugs were covered in soot except for #4, which was white and severely degraded which i attribute to detonation.

While im still at tdc and the cams removed i run a leak down test on cylinder 4 and its at 60% loss and all the air is escaping into the oil pan... Now i know my one quart every 500 miles is due to bad rings. so i begin to remove the cylinder head knowing im going for a full engine tear down. I knew the combustion chambers were going to be dirty but i still wasnt ready for what came out. when i removed the passenger head.


It was worse on the other side. SO i get the heads off and then work on the oil pan. Get the oil pan off and the tarnish was absolutely disheartening.


with the pistons removed there was light scratching on the main and rod bearings. the piston rings were completely frozen in the pistons with carbon. I had the timing covers, block, rods, and pistons sent to be hot tanked and and inspected. Although the ring ridge wouldnt catch on my finger, the machinist said that if he has to ream the ridge he'd bore it .020" over. I told him no, to ridge ream it and hone it and check the clearances

So heres the question should i stick with oem nissan rings for almost 170$ or go with another brand like npr or ???

 

Also with the main bearing selection. Im going oem on the bearings and after the codes im looking at a 3, 5, 34, and 45. should i be worried about the 2 offset bearing selections.

 

ehhh it was worth a try.

For a little update. I picked up the block today from the machine shop and was told everything was perfect. Cylinders, rods, and crank were all well below wear limits with cylinder out of round was off by .0008". Thats pretty much amazing for a block with 160K on it. There was no taper on any crankshaft journal and with a micropolish, it completely removed and fine scratches in the journals. My machinist didnt have to remove and ridge ream because they were non existent and the new crosshatch he put in was nothing short of perfect 60 degrees.

Heads are still being worked on and i still have some parts to order. One of the upgrades is the 2006 vq35de revup oil pump. Same price and a much better pump. OEM rings and head gaskets, rear main seal, OEM timing chains, tensioners, guides, and all orings. Fuel injectors are being ultrasonic cleaned and new O2 sensors. Should run like a kitten

With the block and crank codes my main bearings are going to be 3, 5, 34, 45. and rod bearings are 1, 1, 2, 2, 2, 2.

 

If doing all that work why not upgrade your rods and pistons?

 

Upgrade rods and pistons for another 1600$ is not what i want to do for a 03 pathfinder. I know its not a 350Z but its pretty much the exact same motor and if i was going to upgrade itd be my 07 350Z. This is my GFs pathy and the nico club forum is heavily lacking the tech aspect that this group has.

Cross hatch


journal micro polish