Updates and pic on my blown "New" Sr20det.

[NiekoVon90]

Well guys, I'm new to the Forums, But not cars. Mostly a 300zx Guy. A while back i got my Little 1990 240sx XE coupe, Its now got an SR20DET swap. Forged Wiseco Slugs, Forged Rods, New Oem Crank, All new Timing chain, guids, tensioner/oilpump/waterpump, Fully Rebuilt Head, ect. This Engine is BRAND new, Maybe 1/2mile on it moving it, and taking it around the block. Not sure anyone has ever seen Or had this problem before, And i need to vent Before i take my cadillac phantom and destroy this thing with it. Long Story Short, The Very end of my Exhaust cam (The slot where you would jam a tool and hold the cam in place) Has Broken. A chunk of the Cam Broke off while the engine was running and made its way to the bottom end and now i have this Extreamly loud Deep knocking. Honestly sounds like a rod... It has 50lbs oil pressure at idle, and had 75lbs when it happened. I shut it down immediately and discovered this, And i broke the rest off with my fingers like it just desintigrated... Feel Free to laugh away...



The engine Purring away About 5mins before...



Not Expecting any sympathy, And i'm going to have to rebuild this s*** again. That is the one thing i overlooked because i never locked the cams that way. Moral of the story, When it's apart, INSPECT EVERYTHING!

[Lobo240sx]

Woah that really sux. Were those the original stock cams?? Hopefully you can maybe pull the head off/oil pan and hope it is there? I've seen a few broken cams before on Nissans but not at the end of the cam. The most broken cams I've seen is the Nissan Stanza. The big part of it is people not changing their oil or adding oil lol. Good luck with it bro.

[NiekoVon90]

Yes they were the stock cams, Just A pain in the a** to pull the entire engine apart again... And the oil drains on the back of the head where it would have fallen (Hopefully) Dont even look big enough for it to fit. But im sure it made its way down there. Does that drain straight onto the Crank? or is it just machined to drain into the pan? Which is why im unsure why its knocking. I didnt think it would fall directly into any moving parts, and it was heavy enough to sink and stay in the bottom of the pan. And When it first did it, it knocked really violently, then went away, then came back, then faded out softly, And now it sounds like someone is hitting that damn thing with a hammer. I WANT to ASSUME it's a rod knocking, but that wouldn't just go away (In normal cases) it would continue to get worse... Anyways this car is driving me insane... Haha

[NiekoVon90]

Well, I put it all back together today, everything on the cylinder head looked fine. Started up fine, and didn't knock. Now it makes a strange ticking noise. (sounds like a ticking vg30e lifter when it's low on oil) full of oil, and 75lbs at idle. When I rev it slightly the noise changes, and sometimes it sounds like someone tossed a bolt into the valvetrain. I got under the car and I hear nothing unusual under the engine. It's much much louder up top towards the back of the cylinder head near the firewall. Still pretty lost. And I want to assume that the metal made it's way to the bottom of the pan, or is stuck in a place where it isn't going to do any harm until I tear down the engine.

[NiekoVon90]

Updates, Come to find out, When the engine was built it had 5w30 in it. Which now smells like gas and has the consistancy of water. I started it, and let it warm up and it only had 5LBS of oil pressure at idle. I assume its not enough to keep my lifters pumped up, and Its All Valvetrain noise. Yay, no rod knock... Going to change the oil out to 10w40 and pull both oil pans off and see what the hell is going on if there is metal in there or its someplace else... Hopefully i dont have to tear it down again. between cold start and warm up with the engine running it Didnt make the noise... Anyways, I will keep everyone posted.

[Lobo240sx]

Yes they were the stock cams, Just A pain in the a** to pull the entire engine apart again... And the oil drains on the back of the head where it would have fallen (Hopefully) Dont even look big enough for it to fit. But im sure it made its way down there. Does that drain straight onto the Crank? or is it just machined to drain into the pan? Which is why im unsure why its knocking. I didnt think it would fall directly into any moving parts, and it was heavy enough to sink and stay in the bottom of the pan. And When it first did it, it knocked really violently, then went away, then came back, then faded out softly, And now it sounds like someone is hitting that damn thing with a hammer. I WANT to ASSUME it's a rod knocking, but that wouldn't just go away (In normal cases) it would continue to get worse... Anyways this car is driving me insane... Haha

The galleries in the back I believe do go to the crank. The debris is probably stuck in one of those oil passages and releasing little pieces at a time. Check the oil strainer and pan for debris and metal shavings. Use regular oil no synthetic while breaking in the built engine.

[NiekoVon90]

Well, as far as oil goes, it's going to be mobil 5000 10w40 for break in, since it's conventional. After that its onto mobil1 synthetic 5w40. Still not sure what that 5lbs of oil pressure at idle when warm was about. Definately going to open this oil filter up and see if there is anything unusual. Also going to try and stick a small magnet down that oil drain. I will update later today.

[NiekoVon90]

All metal is out of the engine with no damage to anything. Changed the oil to 10w40, And it was running Fine for about ten minutes (untill warm). I took it to the gas station and i pulled out and Got on the gas, After my quick pull, i lost my oil pressure again, and Clack Clack Clack. Trying to use my brain (and what little common sense i have) and i'm just going to replace the pump. When the engine was built it wasnt replace, Love finding out all this NOW! I've read a few threads around and this is a common issue. Atleast it's not a Rod Knockin. haha

[NiekoVon90]

By the way, The car took 4qts to read full on the dipstick. I know the capacity is about half quart less, But i wanted to see wtf was up with this damn car.

[OutToWinPAHC]

Yeah stop running it, pull the pan, replace the strainer and oil pump/

[NiekoVon90]

Ordering an S14 sr20det strainer, ISIS extended oil pan, and genuine Nissan oil pump tomorrow. Hopefully this solves my problems. My gauge bounces all over the place when I hold the throttle steady. I assume the cylinder head has to come back off to get the front cover and pump off. Soo looking forward to that....

[NiekoVon90]

Have everything ordered, everything is shipped except the oil pan. Damn mobil app and I didn't read there was a wait time of 1-2 weeks for them to restock. Engine is torn down to the head, noticed cylinder 2 was wet. And I had lost a bit of coolant. Assuming it's a headgasket issue, since the head is brand new. But I'm not sure why it would be a HG because it's a Cometic MLS. Anyone else have problems with these things sealing correctly?

[Lobo240sx]

Engine is torn down to the head, noticed cylinder 2 was wet. And I had lost a bit of coolant. Assuming it's a headgasket issue, since the head is brand new. But I'm not sure why it would be a HG because it's a Cometic MLS. Anyone else have problems with these things sealing correctly?

Cometic head gaskets are a hit and miss. Most of the time it has to do with the way it was installed. I'm assuming you are using ARP head studs and not the stock studs. Use some copper spray or compound to get a good seal. You could have some decking issues as well. While taking it apart you are going to lose some fluids?

[NiekoVon90]

It had been burning coolant and oil... Yes ARP head studs. I have the gasket Copper Spray aswell. I assume the deck is fine because it was all checked out prior, and the head is new... So i assume the HG is the problem with the loss of coolant while it was running, as far as burning oil goes, the rings arent seated and im getting a ton of blowby aswell. Im seriously about to sell this engine and just LSX swap...

[240life]

That copper spray on is a joke, destroyed a perfect TOMEI MLS gasket on my Sr..never had any issues before, now the copper spray is all in my coolant and my headgasket is leaking.

[NiekoVon90]

Oh man, you will never guess what I found... She is toast. Found all kinds of metal in the plenum, the rest found its way into the cylinders and tore up EVERYTHING. Pistons, cylinder walls, combustion chambers. All destroyed. Surprised it even ran... Pics tomorrow...

[NiekoVon90]

Oh man, you will never guess what I found... She is toast. Found all kinds of metal in the plenum, the rest found its way into the cylinders and tore up EVERYTHING. Pistons, cylinder walls, combustion chambers. All destroyed. Surprised it even ran... Pics tomorrow...

[NiekoVon90]

Here is the Carnage. The Metal in my plenum was part of my piston Rings (WTF Right?) Apparantly It had no thermostat, was overhead, Melted the pistons, ect. All before i Got it. WHAT THE HELL. Luckily, the crank is beautiful, and i have another short block I am going to get Bored out to 87mm, Throw some JE pistons, and Eagle rods, STD acl race bearings, and a new HG and i should be okay... Hopefully. I can just buy another damn Sr20 for what its costing to build this one. =/
(sorry big pics, just wanted you to see the detail)


Half the ring land on the intake side is gone, and all the top rings on the Pistons were broken and blown into the combustion chambers.

Every Rocker except #2 intake side is fine, this thing must have starved of oil, and i am sure the lifter is siezed.


Think i can Save this? or is it something that will Cost a TON to fix...?


The Cylinder is literally splitting from the Block...It's about 3mm Deep all the way around.


Wow, My BRAND NEW engine... Whatever. Anybody know what i can do with the Head? The combustion chambers look terrible, and i need this car running NOW because my CG5 accord is also giving me problems.

[Lobo240sx]

Looks like the metal shavings and debris clogged the oil cam squirt tubes on your #2 lobe. I'd start by seeing if the machine shop can inspect the head. Most likely in your case you are going to need a new block and head. The top of the piston looks like a lot of detonation and heat.

[NiekoVon90]

Well, I have another block that's at the machine shop right now getting bored out. And the head is getting repaired. Just need my piston/rod combo, bearings, lightweight flywheel and solid crank pulley. Then going to get it blueprinted and balanced to 10k just to be safe. No, I'm not running it that high on hydraulic lifters. Rev limiter will be set @ 8k.

[homeslicej2]

Yikes! That's some bad damage. Hope the new rebuild works out much better and you can get back to enjoying the car.

[NiekoVon90]

We will see, really tempted to just say "F-CK YOU NISSAN!!"
And just sell it off... I'm starting to seriously hate this car. And to make matters worse, the z31 I used to own drives by trollin everyday, and I look stupid. Also just became 'less employed' as I like to call it. Life just punched me in the balls big time...