[michbo62]

I recently bought an 2001 300m for $450.00. I bought it knowing it had engine problems.
Now I am trying to figure out what's wrong with the engine. That's were I need help, as I don't have much experience being able to tell what an engine sounds like if it has a spun bearing, or a bent valve, or a rod knock, or who knows what??

When the engine is idling, I here a bit of a tick or knock. When I give it a little bit of gas It really starts knocking, sounding like its in the lower end??
I think maybe it's a spun bearing, but again, I don't know what that sounds like.
What do you think?

What can I do to figure this out?

[nitromonster]

Hi is like my motor, connected rod is busted.maybe
a+++

[Daytrepper]

I would bet its a spun bearing from your description.

Only way to really figure it out is to remove the oil pan and pull the bearing caps to inspect.

[kamikaze]

which motor? the 2.7 that was in my car did that and it was a spun bearing. so I dropped in a 3.5ho.

[michbo62]

So I need to pull the engine to do this? Or can I get to it from under the car?
Is there anything else that it could be?
If it turns out that I have a spun bearing, do I simply put new ones in? Or does the motor need to be rebuilt? By the way the motor is a 3.5. I believe this was the only motor that was put in the 300's.
Could someone please explain how the bearings could spin. And what is making the rattle noise?

Thanks

[peva]

Essentially - yes. Except 2.7's are in some European M's.

[michbo62]

So I'm still looking for advice.
If it's a spun bearing then that's major bucks right?

[frankiee]

I also think it would be a spun rod bearing.
I just bought a Buick for $500 with a knock and a suspect spun bearing.
!/2 hour in the parking lot to drop the pan and it was a spun bearing.
Put in a new bearing for $10 and drove it home.
Still has a knock to it so later I am going to pull the piston and rod and put a different connecting rod in.
When they spin it means there is metal to metal contact for one reason or another and heat builds up and it attaches itself to the crank and breaks from of the little retaining tabs that hold it in place. So the bearing is going around with the crank and it wears the connecting rod larger.
If it were just a rod knock and it did not spin then just go to the local parts store and get a bearing for $10 and throw it in.
It depends on what is wrong. As said by others. First find the problem then worry about the solution.
A cracked flex plate sounds identical to a rod knock.
Run engine and shut key off and flick key back to run just before it quits.
You might have to do this lots to get the hang of it.
If it knocks just when the engine catches then it is a sign of a cracked flex plate
Best way would be get under there and check it out. Drop the pan and check the rods.
Maybe even a mini movie from your cell or camera and a link to Tiny Pic or where ever you want to put it.
We could listen to it and go from there.

[michbo62]

OK here is the video, what do you think?

[Daytrepper]

Sounds like a spun bearing in the video. Check the torque converter bolts and make sure they are tight.

You can pull the oil pan and inspect the bearings with the engine in the car. However, if it has a spun bearing, it will likely need a crankshaft kit, (new crankshaft and bearings), or machine your current crankshaft and replace the bearings. There is a chance one of the connecting rods will be out of round and need replacement as well. The engine would have to come out of the car and come apart if this is the case.

A spun bearing is a bearing that spins in the connecting rod bearing journal, either from lack of lubrication, or excessive clearances. When it spins it usually tears up the machined surface of the crank and the inside of the rod.

The rattle noise is the connecting rod slamming against the crankshaft because it has excessive clearance.

I would suggest a complete rebuild on the engine, or, pull it out and put in a low mile used (cheapest most reliable route) engine. When I rebuilt my 3.2 I had $2500 plus into it, just into parts....but prices have came down since then.

[michbo62]

Ok thanks a lot, I'll have to do a little checking, maybe I can find an engine.