1jz has rod knock

[oowee623]

earlier tonight i was doing some spirited driving in a canyon with my buddy and while on the downhill i heard a knocking noise passed 3000rpm so i let off the rest of the way down, i checked the oil and it was at the full mark. i drove it past 3000rpm a few times cause i was in denial that a 1jz could develop rod knock then limped it home where it currently parked in my garage:cry:

so now my question is, is the motor salvageable or do i need another long block? what other options do i have?

the car has been through 2 bhg 7mge's and i just got the 1jz swapped by aaron back in january, aside from ecu caps it never had a single problem until now:1zhelp:

 

[tlo86]

2jz bottom end, ~300$

 

[JASONA70]

2jz bottom end, ~300$

:word8kn:

 

[suprahero]

You can get a used 2j block for $300.00 if you're willing to wait for one to become available, and then hope that it doesn't have any problems. I bought one for $300.00 from a guy in Tennessee only to find out it had a spun bearing. You can rebuild your 1jz block and have one that will last you for a very very long time as long as your oilpump is o.k.
Something made you get rodknock, and if you're oil was full then I would want to find out why. Good luck.

 

[OneJSupra]

^^^ i like to know what made your 1j rk as well as to help other 1jz guys from not having it. I check my oil level like my life depends on it before and after driving the car.

 

[jdub]

Something to think about concerning "spirited driving", especially on a road with hard curves and inclines...the oil in the pan will slosh. The oil pump will lower the pan level just by pumping oil through the motor. Lateral G, aggressive braking, and road inclines make it possible the pump pickup to be uncovered, resulting in an immediate loss of oil pressure. It only lasts a few seconds, but it's enough to FUBAR a bearing (especially a worn one). I ALWAYS run my oil a quart over the full mark on the dipstick...cheap insurance that applies to the J series motor too.

I'm not saying this was the cause, but it is a possibility.

 

[blackmaxx96]

You run a quart above full?
How long have you been doing that?

 

[blackmaxx96]

To the OP:
Sorry to hear about your motor... I'm deathly afraid of this as well because this is my second supra and I went through two 7M's on my first one... One was BHG then knock... the other one straight up seized.

 

[jdub]

You run a quart above full?
How long have you been doing that?

For years
There is no downside to doing so.

 

[OneJSupra]

For years
There is no downside to doing so.

Same here but I ran half a quart over the full mark. So far so good.

 

[suprahero]

If one over full is good then two over full must be great................just kidding John, but ever since reading that you do this, I do it on both of our supras as well. Thanks.

 

[di_rosa]

make sure you get a GOOD shop to rebuild yours, i've rod knocked 5 2j's, and 4 of those were freshly rebuilt that only last 200 km's before my oil had so much metal in it, it blinded me in the sunlight. (and no, it wasn't my fault, i cleaned everything out, including oil cooler and turbo, even did 3 oil changes at the 0km mark for each engine).

the oil cooler is VERY important to clean out as it retains a lot of metal. i actually changed mine since my machinist said he couldn't get all the metal out.

 

[webbs7mgte]

agreed find a good reputable shop to do your rebuild or someone who knwos what their doing ntos ome guy who claims he can do stuff and really can onyl do brakes and oil changes lol... but also quick question on the 1jz topic..how much horse power are the stock internals good for on no special tune jsut tune to oem settings

 

[oowee623]

Something to think about concerning "spirited driving", especially on a road with hard curves and inclines...the oil in the pan will slosh. The oil pump will lower the pan level just by pumping oil through the motor. Lateral G, aggressive braking, and road inclines make it possible the pump pickup to be uncovered, resulting in an immediate loss of oil pressure. It only lasts a few seconds, but it's enough to FUBAR a bearing (especially a worn one). I ALWAYS run my oil a quart over the full mark on the dipstick...cheap insurance that applies to the J series motor too.

I'm not saying this was the cause, but it is a possibility.

what he said may be the most propable cause,i wish i had an oil pan similar to the greddy oil pan for SR20's(prevents oil sloshing with the use of flaps on hinges) which my friend that was behind me had :/ or at least a crank scraper...

i'd like to keep the motor a 2.5l by preference so i will check the block and see if i can rebuild it, possibly upgrade it. right now im gonna just park it in my garage until im ready to rebuild it.

also im gonna check my oil filter to see if there was anything wrong with it. i know this may sound stupid of me but i read that stock toyotas were crap so i switched to mobil 1 and coincedently my stock oil pressure guage didnt work afterwards, i didnt think anything of it because ive had it go bad on me before and was gonna replace it but i havent seen and supras in the junkyard lately, but this incedent was about 3 weeks ago which should have done the damage then. maybe another possible cause

edit: why take it to a shop when i can save money doing it myself aside from machine work of course. i know and trust a lot of supra owners here in long beach that can help me out. i dont trust any shops here for engine rebuilds anyways

 

[improved]

For years
There is no downside to doing so.

I've added a quart over in my 7m with no ill affects. Although, I did this because it was verified on the forums before hand.


Jdub did you happen to check the clearance of the quart over on the 1J?

Matt-

 

[jdub]

The sump is big enough...at least as large as the 7M. There are several guys here doing it and you can tell zero difference in the way the engine runs.

Think about it...what happens to the oil when the motor is running vs shutdown?

 

[ForcedTorque]

1jz has rod knock

HAHAHAHAHAHAHAHAHAHAHA



To the OP........I say this on behalf of all 7M owners, and is in no way directed at you but at your thread title instead.

 

[Jostar]

Another way to rod knock any motor is...................Detonation/knock/misfire, That's how i blew mine first, The damn stock ecu was the culprit on my car...

 

[oowee623]

HAHAHAHAHAHAHAHAHAHAHA



To the OP........I say this on behalf of all 7M owners, and is in no way directed at you but at your thread title instead.

no offense taken, i was lead to believe these motors were virtually indestructable

Another way to rod knock any motor is...................Detonation/knock/misfire, That's how i blew mine first, The damn stock ecu was the culprit on my car...

not in my case, my ecu has new caps and i only use premium gas

 

[ForcedTorque]

I really do feel sorry for you. I'm not the one usually in the 7M/1J arguments