blew my 2j......suggestions?

[dirosa]

well, i always take note of my oil pressure (greddy sensor and gauge), and have noticed it lower than normal at hot idle (usually around 1.2bar, now down to 0.9bar), so i decided to drain the oil and see what's going on..........sure enough, metal in the oil.

now, since i have caught it before there's been any real knocking, do i:

a) replace the engine with a jdm one?

b) rip apart the bottom end, change the bearings, thrust washers, oil pump and get the crank micro-polished? i can get a jdm engine for like $1300, but all that is going to cost around $500-$600, plus all the time for me to do it.........though, i have changed every seal in this current one, so changing them all again in a jdm replacement would jack up the bill some more


and lastly, can we play the blame game? how the F*** did it blow?

• i NEVER opened up the engine
• i never ran low on oil
• changed oil every 5000km or less
• always ran synthetic oil
• never over heated

the only thing i can think of is i never changed the jdm oil pump, and maybe it starved the engine. it's just odd that after two years, it decides to go. i've had the same oil pressure for the past two years, then this. all i did with that engine was slap on my exhaust manifold and turbo, and go.

 

[bioskyline]

i chose option b, then you know what you have, vs a JDM mystey engine that you dont know its history.


as for why it blew, i was already a jdm motor? only thing i can think of is previous damage from the previous owner

 

[destrux]

Could have been contaminants going in with the oil or filter, oil temps could have gotten too high (coolant temp isn't a good indicator of oil temp). Could have been caused by contaminants that were in the turbo CHRA if the motor you took it off of was blown. Could have knocked dirt in while changing a seal or gasket and it made it's way into the oil pump.

Lots of possible ways, but figuring out what exactly caused it is the trick, otherwise you could end up with a repeat.

Previous owner damage is unlikely to surface after two years, unless you put less than 10K on it in those two years or something.

 

[dirosa]

wow, super fast responses, thanks guys........

yes, it was already a jdm engine (can't afford a usdm one, sorry)

the turbo was freaking brand new when i got that jdm engine, so i probably gotta rebuild that, but it's ball bearing, so i'm boned

i'm usually pretty good when changing seals and working, cleaning the area with brake cleaner and a rag, so i doubt i would've knocked enough dirt (if any) to cause any serious damage.

destrux, you bring up an interesting point about mileage......i actually am lucky that i don't drive very far to work, and would have to say that yes, under 10k in 2 years is totally possible. i did notice when i changed the valve stem seals that there was a lot of sludge buildup around the cams and valve springs and surrounding areas. but it was like that from day i got it, so i changed the oil a few times right off the bat, and figured it couldn't get any worse, and i would be ok. if it wasn't a turbo engine, i would've ran anti-sludge chemicals, but i know it thins out the oil, and is dangerous for turbo's, so i didn't. could it really have been sludge?

 

[f00g00]

If an oil port is blocked then even though you could have good pressure something could be oil starved.
When slick 50 came out I bought some and put it in my 72 280SE 4.5 mercedes hoping to bring a high mileage motor a little more power while all it did was plug up my overhead cam oilers and my lobes were ground down and I lost some bearings. This all happened within 3000 miles. The whole pan had metal in it, and there was metal everywhere when I pulled a valve cover. Luckily I got stationed in Japan and got a low mileage 73 450SE which I shipped back and put that motor in.
I don't put any additives in any more.
How much metal are you talking about?

 

[te72]

As for which route to take, I would stick with the engine you have, simply for the knowledge of knowing what you're up against. A new engine always brings about new mysteries.

 

[kneedragger85]

Was this a singled GTE? What turbo, tuning, & AFR's did you have?

 

[dirosa]

As for which route to take, I would stick with the engine you have, simply for the knowledge of knowing what you're up against. A new engine always brings about new mysteries.

i agree with you there, though if i stick with this engine, i don't know what caused it's destruction, and therefore can't prevent it's destruction a 2nd time if i rebuild it without fixing it's problem.


i was running a gt4088r, tuned with proper afr's (11.5:1 under full boost, 14.7:1 at idle and cruise)

 

[Backlash2032]

Stick with what motor you have.

A) You don't have the JDM motor mystery
and B) You will likely find the source of the problem when you tear down your current engine.

 

[te72]

i agree with you there, though if i stick with this engine, i don't know what caused it's destruction, and therefore can't prevent it's destruction a 2nd time if i rebuild it without fixing it's problem.

Well, you're gonna need to pull the engine out anyway, might as well get a stand and start dismantling the motor, you're bound to find some hint as to the problem anyway. Worst case scenario, you can at least take some pictures and hope someone on here can help.

 

[dirosa]

yeah, i'll be pulling it next weekend i think. i'll post up pics.

i popped the valve covers and took at a look under some cam caps, and they're scored...........not horribly, just not perfectly smooth. not a big deal right? might loose a bit of oil pressure there, but nothing major right?

 

[te72]

Sounds to me like the oil got a bit too hot. I wouldn't be surprised at all to find that my motor is in that boat as well, although our ambient temps are rarely over 90°, and the worst I've ever done on a warm day is maybe a 0-130 run... who knows. Will be doing a semi-teardown/inspection of mine when it goes in the other shell.