Rod bearings 97 3.8

My son's base model began knocking horribly and I'm pretty sure at least one rod bearing is fried. The engine turns so I'm pretty sure it's not seized but it does draw alot of current when cranking, the terminal and battery wires get hot. I'm on the fence on this one. Should I junk it or repair it? It's a v6. Anyone here replace rod bearings on a 3.8? How difficult is it and is a base model mustang worth the tear down and rebuild? I would have to replace all the connecting rod bearings, to be thorough.
 
Depends on condition.is it a nice base model mustang? I wouldn’t say a tear down/rebuild of the 3.8 is much better/worse than most other engines. The main deciding factor is gonna be cost. Parts/machine shop/tools etc.
Have you considered dropping in a used engine?
 
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+1 on above.

+1 on machine work is very expensive these days as well as the parts do add up fast when doing an engine rebuild.

For the whole salvage yard motor route try searching car-part.com. However given the age of the car it's possible that any salvage yard motor might in of itself not be any better than a "core" itself.

To me it depends upon such factors as:
  • is the rest of the car in good shape.
  • what is the car worth to REPLACE. Check out craigslist to see what other cars could be purchased for about the same repair budget.
  • How handy are you with regards to major engine work? For example if you need to pay a professional to do the work then the answer hands down is no. The car is not worth repairing.
  • Is this a daily driver or a project?
 
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I do appreciate the input. And honestly, its not in the best shape BUT I paid 400$ for it which is a fraction of it's worth. The frame is straight, the engine doesn't smoke and as it was running the transmission shifted fine. I should get estimates on this. I'd like to do it myself but prepping an engine hoist in my apartment community just wouldn't fly. As I understand this particular repair, the oil pan removal is really all the access I need once the engine is hoisted, correct? No need to drop piston or head seperation?
 
+1 on above.

+1 on machine work is very expensive these days as well as the parts do add up fast when doing an engine rebuild.

For the whole salvage yard motor route try searching car-part.com. However given the age of the car it's possible that any salvage yard motor might in of itself not be any better than a "core" itself.

To me it depends upon such factors as:
  • is the rest of the car in good shape.
  • what is the car worth to REPLACE. Check out craigslist to see what other cars could be purchased for about the same repair budget.
  • How handy are you with regards to major engine work? For example if you need to pay a professional to do the work then the answer hands down is no. The car is not worth repairing.
  • Is this a daily driver or a project?
I appreciate the input. It's a daily driver and it's in fair shape, I bought it for a song though- 400$. I honestly don't think it needs an engine. I need to remove the sparks and see if the engine turns by hand just to be sure.
 
I would cut apart the oil filter looking for babbit material, good chance the mains will need replacing too at the least.If the crank is damaged(very likely if it is knocking) you will probably have to pull the engine(when I was young a guy came out and turned the rod journal in the driveway on my '56 Chevy but not sure if this is still a viable option, it later broke the crank in half). Myself I would dump the car and start over, I have too many bad memories of money pit cars after owning 34 or so.
 
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I would cut apart the oil filter looking for babbit material, good chance the mains will need replacing too at the least.If the crank is damaged(very likely if it is knocking) you will probably have to pull the engine(when I was young a guy came out and turned the rod journal in the driveway on my '56 Chevy but not sure if this is still a viable option, it later broke the crank in half). Myself I would dump the car and start over, I have too many bad memories of money pit cars after owning 34 or so.
Cut open the oil filter and look for debris -that is a veteran move. I appreciate that. And yes money pit cars, I've been blessed to have avoided those- so far anyway. Thanks for the reply.
 
I do appreciate the input. And honestly, its not in the best shape BUT I paid 400$ for it which is a fraction of it's worth. The frame is straight, the engine doesn't smoke and as it was running the transmission shifted fine. I should get estimates on this. I'd like to do it myself but prepping an engine hoist in my apartment community just wouldn't fly. As I understand this particular repair, the oil pan removal is really all the access I need once the engine is hoisted, correct? No need to drop piston or head seperation?
I just wanted to make sure that I'm understanding what you are asking. Are you asking if it's possible to perform the repair with just the oil pan removed?

FWIIW the Mustang has a difficult oil pan to remove. The K-member needs to be removed. The engine will need to be supported from above.

If asking for an opinion I think it's short sited to attempt to do this level of engine repair with the motor in the car. The Mustang's motor isn't all that hard to remove. Once removed and on the engine stand access is soooooooooo much easier. Plus if there is unexpected damage the motor will already be out.

It's not really possible to replace all of the lower end bearings with just the oil pan removed. Because the crank can't be removed with the engine attached to the transmission.
 
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I just wanted to make sure that I'm understanding what you are asking. Are you asking if it's possible to perform the repair with just the oil pan removed?

FWIIW the Mustang has a difficult oil pan to remove. The K-member needs to be removed. The engine will need to be supported from above.

If asking for an opinion I think it's short sited to attempt to do this level of engine repair with the motor in the car. The Mustang's motor isn't all that hard to remove. Once removed and on the engine stand access is soooooooooo much easier. Plus if there is unexpected damage the motor will already be out.

It's not really possible to replace all of the lower end bearings with just the oil pan removed. Because the crank can't be removed with the engine attached to the transmission.[/QUOTEM
 
Correct. Once the engine is clear and separated from bell housing, hoisted mid-air and the oil pan removed. My question was more toward NOT having to separate heads, drop pistons, timing gears and belt. Is replacing spun bearings possible with the engine hoisted, oil pan off and without complete disassembly on a 3.8? I'm hoping to approach( or walk away from ) this project as prepared as possible. I appreciate any input as this would be my first crack at replacing rod bearings.
 
If the rod bearings are damaged likely the crankshaft at least needs to be ground. I wouldn't even attempt this without removing the heads and disassembling the bottom end. Also the 3.8l V6 is notoriously difficult to get the head gaskets to seal. I wouldn't try to reinstall the heads without having a shop that really knows what they are doing surface the block and heads.