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Spun a rod bearing Ugh!! It torn down FEW PICS

Uno99

Uno99

Donating Users
Came off the HWY and heard a knock. I limp it home and parked it right away. Finally got into it. Cylinder 1 spun the rod bearing. Not to broke up about it. Parts list is all done and it will be off to the machine shop on monday. Cant wait for the UPS man to arrive next week.













 
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Im not gonna risk getting a tired beat up engine when I can do the work. The chassis on has 104K on it and is pristine. Its my DD and I will just have more piece of mind if I rebuild it myself. Another big factor is the hot tanking is free and the machining is very minimal seeing how my buddy own a small machine shop.
 
Only reason I ask is MOST rebuilds don't last very long that's why most people find a JY engine and throw some new gaskets and seals on it. If you can do the work and machining then that should cut down a lot of cost. Plan on keeping the same rods and pistons id assume? Just machining and new bearings for the rebuild?
 
yeah rods and pistons are fine. I picked up all ARP hardware as well. My 98 S1X 3.0 setup lasted so im hoping I can repeat that but going with a VS cam this time and just a 3.4 pulley.
 


Uno99, I'm working on the same problem. 99 GTP with a rod knock. Spun #3 crankshaft journal / connecting rod bearing. Viewed the forums and it seems rod bearing failures are common. Did you find any other thing that might have cause the failure?
The engine I'm working has a worn camshaft bearing. It's worn down into the copper babbit. Could have caused oil starvation at the rod journal. I have a picture of the bearing, had trouble uploading.
 
Hey Flashman i use photobucket to host my pics. Sign up for a free account there and upload your pics. You can resize them as well and then they have the links you can copy into your post so we can see your pics. As for how mine spun the only think i can think of is i did find some small pieces of rex RTV in the oil pickup tube screen so possibly some got stuck in and oil passage somewhere and starved it for a bit. I still need to open up the oil pump but i broke my torq bit so i need to go get another
 
No clue what caused the rod bearing to spin. Only thing left is possible rod bolt stretch??? I dropped the block crank and all rods off to get checked cleaned up and spec'd out. Gonna be a week turn around. All parts are here so im just waiting. I power washed and degreased some of the engine bracket and mounts today.
 


If you search on James 400TurboSBG guy.. you'll find he cut apart a couple of engines and found oiling deficiences. I think the main post is on 3800Pro. Well worth a read if you are going to rebuild.
 
Uno99, very clean engine hanging on the engine hoist. Let me know how the machinist is repairing the crankshaft / rod journal. Thanks
 
Will do. Ill also have him wrireup the machining cost withput my "friends & family" deal so you have an idea what that may cost you
 
Flashman said:
Uno99, very clean engine hanging on the engine hoist. Let me know how the machinist is repairing the crankshaft / rod journal. Thanks
Click to expand...

usually you end up with a reman crank, which is welded up and then ground back to spec.

ive seen 2 of those break right at the weld, one of em took out a buncha expensive parts (cam, rods, pistons, chainset, and 8 valves)....and the crank snapped at just off idle while making a left turn

i think you can still buy new cranks but i believe its over 800$.

only way to get a good crank is to buy a good used motor...which my last one cost me 150$
 


#1 rod and cylinder spun but im think it may only need a polish rather than a turn but ill let the pro's make that decision. I also brought in all the other rods and end caps too so they can be checked. I also found out the car has a 97 remaned engine in it?? None of that came up on the auto check and carfax. So nice of the seller to be so honest with me.
 
Just talked to my buddy at the machine shop they confirmed the rod bolts streched causing the #1 rod bearing to spin. Im having them just install the springs and freshen/cleanup the heads. Gonna re-ring it as well. Hopefully it will be back to me by this friday.
 
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