Bearing devistaion and crankwalk

[T is for TURBO]

Well, Some of may have read my last thread about my engine a few weeks ago. Well I finally got the engine pulled out and this is what I found. Rod beaing #2 spun, and Rod bearing #4 is just destroyed. My question is, do you think crankwalk caused the bearings to spin/destroy themselves, or do you think it was just in the process of walking and the bearings spun due to oil starvation as rod cap #4 was BONE dry when I took it out.
Here are some photos.

 

[T is for TURBO]

Here are a few more

 

[Rick@AP]

Well, crankwalk, if bad enough, will cause the thrust bearing to wear. The particles from the bearing, especially metal ones, can circulate through the oil and cause the other bearings to go bad. Usually though the crank angle sensor gets destroyed by the movement of the crank long before enough metal is released into the system to cause a problem with the other bearings.

Your oil looks a little watery, are you sure you don't have a leaking oil cooler or bad headgasket?

 

[T is for TURBO]

well, about half of the oil that was in the oil pan before this happened only had about 200 miles on it, so that might be why it looks watery. However there may be a small leak somewhere, but if there it is very small.
On another note, I had no idea that the motor was even walking until this happened. There were no signs at all, clutch was pretty good, CAS was still intact, no RPMs dropping while pressing the clutch, no ticking noise other than valve train noise. I just thought I lost oil pressure and starved that bearing of oil. But when I pulled the caps off yesterday, thats when I noticed all the damage.
Well, Im not to worried about it, I plan on swapping a 6 bolt in anyway. But I just wanted your opinions.
Also, what do you guys think about rebuilding? Worth it? I would only rebuild it for a spare motor if I did rebuild. Otherwise Ill just part it out I guess.

 

[InvaderGSX]

Another thing to consider is your oil pump/front case went bad. Did your car have oil pressure on the gauge? That will definitely make a rod bearing go if you have lack of oil pressure from a bad front case.

 

[timloomis]

you definatly started to walk,that thrust bearing is down to the copper lining.personally,id just part that motor out,because youll at LEAST need a new/turned crank,new rods,and a lot of cleaning up and machine work.

 

[InvaderGSX]

Definitely buy a new crank. I have had bad experiences with machine shops trying to machine them to spec. That crap never works. Buy a new Topline or Eagle crank. And replace all 4 oil jets in the block and the oil pump. People never replace the oil jets and that is the key thing in my opinion with crankwalk.

 

[T is for TURBO]

Well, I had oil pressure (according to the crappy stocker gauge), But then I heard a loud popping noise (which I think is was the rod bearing being ripped in half. After the popping noise, The oil light came on and I shut it down...

As for rods, do you really think I'm going to need new rods? I havn't pulled the crank yet to inspect them, but from what I can tell they still look good, as do the cylinder walls... But I guess I won't know until I pull it completely apart..

 

[InvaderGSX]

Yeah your best bet is to drop the motor off to a machine shop and have them check it out. Most likely the rods can be machined. They might tell you they can machine the crank, but I wouldn't. It'll just take a crap quickly. And they'll hit you for over $150 to machine and balance the crank so you mine as well spend a few extra to get a brand new crank. If you plan on making a lot of horsepower you mine as well get new rods, but if not then keep the stock ones. You can get Eagle rods for around $300. Pistons rarely go bad on these cars comapred to other cars.

 

[T is for TURBO]

Well I don't plan on making much more stock power with the 7 bolt.. Im just going to keep it around as a spare, (or put it in my geo storm as im going to do a 6 bolt swap

(Any one in the eastern wisconsin area wanna help me do a 6 bolt swap )

 

[94awdcoupe]

The main bearings tell the story. Engine was run on low oil pressure for a long time (weeks) or run with no oil pressure for a short time (minutes) The thrust isn't telling anything, it was run at low oil pressure as well.

 

[timloomis]

thats also true.thats why i have an autometer gauge now.my dummy light came on before and the stocker said i still had good pressure.sounds like your gauge crapped out.

 

[blackGSX2g]

The main bearings tell the story. Engine was run on low oil pressure for a long time (weeks) or run with no oil pressure for a short time (minutes) The thrust isn't telling anything, it was run at low oil pressure as well.

I agree. Your main bearings look about as worn as the thrust surfaces of your thrust bearing. I wouldn't point to crankwalk as the cause of this, but rather poor oil pressure as 4G63-GST pointed out. It looks like you were getting bearing wear all over, not just the thrust bearing.

 

[T is for TURBO]

I agree. Your main bearings look about as worn as the thrust surfaces of your thrust bearing. I wouldn't point to crankwalk as the cause of this, but rather poor oil pressure as 4G63-GST pointed out. It looks like you were getting bearing wear all over, not just the thrust bearing.

Thats what I was thinking as well. My theory is that I lost oil pressure (I think the front case took a dump, not sure yet, I have to rip it down) and it killed everything (except cylinder #1 rod bearing looks somewhat okay, (closest to front case)). Do you think the sudden loss of oil pressure could have caused the crankwalk? By the way, there isn't any noticably play in the crankshaft. I can push/pull on it an to does NOT move...

How do you think the turbo handled this? only has 210 miles on it

Ill check the cam towers and see what they look like when I get a chance...

 

[T is for TURBO]

well, Its been a while since I have posted in this thread. The block has been completly torn down. Damage: Cylinders walls need to be at least honed, if not bored, head looks good. Turbo has a little shaft play, but I think it will be fine, rods I don't know, pistons have some wear, but I think they are okay, crank is done for, as well as all the bearings. Buy the looks of it, my best guess is that the front case took a shit. I don't know of the balance shaft started to back out or what, but, well, here, take a look for your self, a picture is worth a thousand words...


Edit: The motor is not being rebuilt. I have a full six bolt longblock waiting to be dropped in. Im just have to eliminate the balance shafts, replace water pump, t-belt, tensioner and pullyes, mount water pipe, and turbo, then drop it in!

 

[Turbo Shogun]

Ouch ... My oil pump housing kinda looks like that too.

Machine shop beadblasted my head and didn't flush it out. WTF And my cam bearing caps were torqued to 55 ft/lbs ... My cam journals are scored and so are my cam journal saddles on the head. I don't know if I'll have to get a new front case yet ...

 

[T is for TURBO]

Ouch ... My oil pump housing kinda looks like that too.

Machine shop beadblasted my head and didn't flush it out. WTF And my cam bearing caps were torqued to 55 ft/lbs ... My cam journals are scored and so are my cam journal saddles on the head. I don't know if I'll have to get a new front case yet ...

personally, I wouldn't F*** around with a front case that has any sort of damage. I would replace it... but thats just my .02

55ft/lbs!!! isn't it supposed to be more like 14? I hope the machine shop is paying for the damages!

Good luck man!
-Shawn