rod bearing woes

[zachm611]

i bought a parts car for $400 mainly so i can do a AT to MT swap in my supra, ive been tossing around the idea of keeping this car for a future 2jz swap, not sure yet we'll see what its future holds. now to the point.. it has a jdm 7mgte. i bought the car with rod knock so i finally got around to tearing apart the engine to find plenty of metal flakes. after removing the end caps on the rods i found a severely eaten bearing on #3... what would cause something like this? also the mains were waayyy over torqued the impact gun wouldnt remove them, had to use a breaker bar.

i have high res pics if anyone would like to see.

edit: 2nd picture has a bearing from a different cylinder to compare the 2.

 

[TheNewRed]

i bought a parts car for $400 mainly so i can do a AT to MT swap in my supra, ive been tossing around the idea of keeping this car for a future 2jz swap, not sure yet we'll see what its future holds. now to the point.. it has a jdm 7mgte. i bought the car with rod knock so i finally got around to tearing apart the engine to find plenty of metal flakes. after removing the end caps on the rods i found a severely eaten bearing on #3... what would cause something like this? also the mains were waayyy over torqued the impact gun wouldnt remove them, had to use a breaker bar.

i have high res pics if anyone would like to see.

WOW, looks like an oiling issue...:aigo:

 

[iamshawn]

bam >> http://engineparts.com/publications/CL77-3-402.pdf

look kinda like the hot short... oil starvation

 

[TheNewRed]

i bought a parts car for $400 mainly so i can do a AT to MT swap in my supra, ive been tossing around the idea of keeping this car for a future 2jz swap, not sure yet we'll see what its future holds. now to the point.. it has a jdm 7mgte. i bought the car with rod knock so i finally got around to tearing apart the engine to find plenty of metal flakes. after removing the end caps on the rods i found a severely eaten bearing on #3... what would cause something like this? also the mains were waayyy over torqued the impact gun wouldnt remove them, had to use a breaker bar.

i have high res pics if anyone would like to see.

edit: 2nd picture has a bearing from a different cylinder to compare the 2.

Oh yeah....heres how to solve that, READ ALL OF IT!!!!http://www.supramania.com/forums/showthread.php?t=31378

 

[zachm611]

awesome link thanks a lot for it.

The New Red i have already read that for my engine build, i was no way related to any damages this engine has. lol but thanks for the tip

 

[TheNewRed]

awesome link thanks a lot for it.

The New Red i have already read that for my engine build, i was no way related to any damages this engine has. lol but thanks for the tip

Actually "rod bearing failure can be caused by many things, Other than the common lack of oil, improper clearance at assembly, improper machining, failure to torque properly, and my favorite- ignition knock, are all causes of bearing failure"....im just saying more then likely thats why yours failed!:3d_frown:

 

[zachm611]

i heard from a friend of the owner that when it broke down there wasnt any oil on the dipstick so that sounds like the winner.

 

[TheNewRed]

i heard from a friend of the owner that when it broke down there wasnt any oil on the dipstick so that sounds like the winner.

Yes Yes, my good sir!:biglaugh:

 

[starscream5000]

Actually "rod bearing failure can be caused by many things, Other than the common lack of oil, improper clearance at assembly, improper machining, failure to torque properly, and my favorite- ignition knock, are all causes of bearing failure"....im just saying more then likely thats why yours failed!:3d_frown:

I've got another one to add to that, coolant mixing with motor oil. Due to a BHG most likely, or a really ignorant individual who can't tell the difference where to put coolant, and where to put oil.

This mix will create an acid, which eats away at softer metals relatively quick (rod and main bearings here).

This is most likely the #1 cause of rod knock after a BHG repair.

 

[TheNewRed]

I've got another one to add to that, coolant mixing with motor oil. Due to a BHG most likely, or a really ignorant individual who can't tell the difference where to put coolant, and where to put oil.

This mix will create an acid, which eats away at softer metals relatively quick (rod and main bearings here).

This is most likely the #1 cause of rod knock after a BHG repair.

Excelent point, you would have to be REALLY stupid to let that happen!

 

[starscream5000]

Happens A LOT more around here than the others that you've mentioned .

 

[JustAnotherVictim]

Due to a BHG most likely, or a really ignorant individual who can't tell the difference where to put coolant, and where to put oil.

I would link to another thread, but I won't. :biglaugh:

 

[IJ.]

Bitchy thread

 

[JustAnotherVictim]

Yea that one. :biglaugh:

 

[themadhatter]

that might be the worst rod bearing i've ever seen

 

[zachm611]

now im rather curious.. did someone actually mix up where to add coolant/oil?

and themadhatter its much worse in person.