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Rob's GTS engine pull

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Old 05-13-2009, 12:34 AM
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86'928S MeteorGrey
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Default Rob's GTS engine pull

I got a shot of Rob and Mark while the engine was getting ready to be pulled. Excuse the cell phone photo. Here, the power steering resevoir was about to be dumped... The last step before yanking the engine. Unfortunately, I had to go to work so I missed the grand moment. The oil filter had some flakes. Don't know the prognosis yet, but I'm hoping for the best. No real hiccups at all while I was there. The car really is nice. It's going to be a great stroker recipient...
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Old 05-13-2009, 12:57 AM
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Rob Edwards
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I'm still in the throes of the bedtime ritual so pics will come later but the verdict is the #2 rod let go. It let go in an interesting way. Pictures at 11....
Old 05-13-2009, 01:28 AM
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RyanPerrella
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Thats me in the background sniffing the rear end!

Rob, so does the rod just break, or does the bearing due to oiling or something and cause the rod to go as it did? I was trying to figure out how a rod just decides to suddenly BREAK, so i figured it must have been caused by the bearing failing then....... boom
Old 05-13-2009, 02:36 AM
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Rob Edwards
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Ok, some carnage pics. Bottom line, there was no bearing shell left in the remains of the big end of con rod #2. Looks like it pounded out the bearing, then spun it, then broke the connecting rod. Then the busted rod hit the crank (taking a big chunk out of the counterweight), bending the con rod 90 degrees and spewing fragments all over the place.


But this is weird- it broke at the big end, not along the neck. I took the remains of the #2 rod cap to Greg, who pored over it like a jeweler looking at a Tolkowsky cut round brilliant. His first question was 'where are the rod nuts?' To which the asnwer is, I don't know. The rod nuts are torqued to 55 lbs and they leave marks on the rod cap, as you can see in this pic. Some of the marks have been worn down on one side, as if the bolt stretched and the nut moved side to side a little, then perhaps it just unscrewed itself (or explosively failed and got launched through the oil pan

Perhaps more will become clear when I get a chance to tear the thing down all the way.

Closeup of nut markings:




Remains of rod bearing surface:


Nice strong rod bolts:



Here are the bits as they lay in the oilpan, and the hole:


Overview of the whole bottom end:


#2 broken rod, bent 90 degrees. I'm going to have to remove the crank and girdle and then cut the connecting rod off in order to be able to get the piston out of the cylinder:



Judging by the chunk out of the counterweight, I think this crank is done. Too bad, as the bearing surface doesn't look all that bad (but what do I know...). I don't see anything from this limited veiw that makes the block junk but I can't imagine how the counterweight could take that kind of hit and not crack something in the block somewhere. We'll see.



Oil filter shiny bits:



Got the car flatbedded home, and gave her a much needed bath. She cleans up nice:








May be a while before Jen's car is back indoors....








Anyway, it was nice to meet you Mike, and thanks for all the help! Ryan was there to help out as well. and William A too. Big thanks to Mark A. for helping me out yet again!!!!!11!!!eleventy!1!

Old 05-13-2009, 02:40 AM
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GregBBRD
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I got to see some of the pieces...very strange. Unfortunately, I got a feeling that some of the important pieces to the puzzle might have been washed away, already.
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Old 05-13-2009, 03:07 AM
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mark kibort
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cant you weld up the crank and make it good again? I hate to see a GTS crank go in the dumpster.

How did this happen? any warning? what oil used?

Sorry to hear about the damage. Im sure you will make it better, stronger than before.
Best of luck.
Mk
Old 05-13-2009, 03:36 AM
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RyanPerrella
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Originally Posted by mark kibort
How did this happen? any warning? what oil used?
AMZOIL

No joke




Yeah i commented too as to the strength of the bolts, the nuts missing was also interesting and it appears that thats what caused the hole in the pan which Rob didnt show us a pic off. Actually when i looked at the location of the hole it appeared that cylinder 6 would have shot the nut based on the cylinders being offset, the hole seemed (at my first glance) to look like it would have been cyl 6, but it was 2.

Also interesting to see the rod cap in 3 pieces. Interesting that the big end broke, more still that the cap broke, even further that cap isnt in just 2 pieces but 3, that does seem very odd. (EDIT: The cap is in 2 pieces NOT 3) How the hell would the nuts loosen themselves though? The threads on the bolts looked terrible but i assumed that was because the nuts must have been launched off them.

Last edited by RyanPerrella; 05-13-2009 at 04:05 AM.
Old 05-13-2009, 03:40 AM
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Oh and wow does that car clean up nice!

I'll try and get you some good engine degreaser too when i return your tools on Friday so you can clean up that engine bay.

LOL i love how your loafers are like on display too in front of the engine!
Old 05-13-2009, 03:52 AM
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It is easy to take for granted the forces exerted in these engines even under non-max loads... until you see the results when something goes wrong. Pretty amazing. And as a '93 GTS owner seeing it in person turned my stomach a little.

Aside from a little engine "repair", Rob has a very nice car to work with. It looks great and will be a real prize when he gets done.
Old 05-13-2009, 04:23 AM
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86'928S MeteorGrey
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It was good meeting you. Glad I could help out. The definitive evidence probably shot through that little hole and is still lying on the side of I-5 somewhere. Could it have simply been a re-used or incorrectly torqued nut backed off a little and caused all of this? Could it have been a #2/6 bearing replacement (preventative) that wasn't correctly fit? Did you get any maintenance records from the po? Was it just a lack of oil pressure there at one point on the track that started it on its way to failure? Maybe a little of all... Or was Amsoil directly to blame? Too many questions... We'll probably never know. Looking forward to the teardown photos.
Old 05-13-2009, 04:25 AM
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Originally Posted by 86'928S MeteorGrey
It was good meeting you. Glad I could help out. The definitive evidence probably shot through that little hole and is still lying on the side of I-5 somewhere. Could it have simply been a re-used or incorrectly torqued nut backed off a little and caused all of this? Could it have been a #2/6 bearing replacement (preventative) that wasn't correctly fit? Did you get any maintenance records from the po? Was it just a lack of oil pressure there at one point on the track that started it on its way to failure? Maybe a little of all... Or was Amsoil directly to blame? Too many questions... We'll probably never know. Looking forward to the teardown photos.
Mike,

I didn't realize you where who you are until I asked Rob after you left.

Thanks again for the Craigslist finds!
Old 05-13-2009, 08:52 AM
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So can the block be salvaged?
Old 05-13-2009, 09:35 AM
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Originally Posted by Marine Blue
So can the block be salvaged?
Yes so how are you going to repair it? Can you get away with a crankshaft, a connecting rod and piston for #2 and new bearings?
Old 05-13-2009, 10:45 AM
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Are you sure the block can be salvaged? As I see the connecting rod is wried, so I suppose that the cylinder should suffer of ovalisation. Then, it is likely that the roundness is greater than the odds of repair.

Puyi
Old 05-13-2009, 12:32 PM
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Hopefully the block and crank can be repaired. Even though you won't be putting them back in the GTS for a while. When the day comes these cars hit big money, that original #'s engine is going to be required (or one like it...).

But moving back to happier thoughts, that is going to be a wicked GTS with the 6.5L under the hood!!

As a fellow GTS owner, I found those pictures very disturbing.

Was this an early or late VIN '93 GTS?


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