What are the signs of a spun rod bearing?

[badgsx]

This is on a second gen 7 bolt if that matters any.

 

[myblack98gst]

the BIGGEST sign I can tell you (went through 5 sets of bearings on the last motor!!) is at 2,500 rpms there is a destinctive tapping sound. either just cruising at that rpm or sweeping past it accelerating.. I dunno why it is but every time it started making that noise when the bearings got worn..

other than that buy a new oil pan gasket and spend about 30 minutes dropping the oil pan and check for metal in the bottom

 

[badgsx]

Would the tapping still be there with the engine at idle or when revving the engine with the transmission in neutral? And does it make the engine run any differnt other than the noise?

 

[temfate]

I too have heard (felt) this tapping... It happened at about the exact rpm range already mentioned, and it bothered me to no end. But I had no clue what it was and ignored it; until it was WAY to late! Fix it sooner than later if you have it!

 

[awd4g63]

If you spun a rod bearing, you'd know it. There would be metal flakes all in the oil. Also, there would be a pretty loud knocking noise, and that's only if that crank journal didn't lock up.

If your bottom end is on its way out, check the oil for signs of metal. Can you explain any noises or different driving behaviors a little more?

 

[44pirate]

Would the tapping still be there with the engine at idle or when revving the engine with the transmission in neutral? And does it make the engine run any differnt other than the noise?

Yes.
It doesn't run any different until it really lets loose.

 

[badgsx]

Well this just started yesterday. Its making a knocking sound while driving. I cant hear it while accelerating but as soon as I start cruising you can hear it and feel a vibration thru the gas petal. When you let off the gas and decelerate it gets even louder. But if you pop it in neutral the sound is gone. Also if you rev it up at idle there is no noise either. The car is still running fine and boosting fine. I'll change the oil tommorow and see if I find any flakes. What can happen if I keep driving it?

 

[skibumexicano]

If you had a knock..You'd know it and feel it...The car would also run like ass! I'd do the basics...Compression test, and check the oil for any signs of metal shavings...Good luck man..Dan

 

[awd4g63]

You can really screw something up if you keep driving it. Refrain from driving the car as much as possible until you get the problem fixed.

To be honest, it sounds more like a drivetrain problem, or just something loose and rattling around more than a rod knock; but be careful driving it if you have to. As Dan said, do some tests and figure out what the problem is.

 

[BigBADGSX]

Serious loss in power along with the knocking noise your talking about is usually what goes along with a spun bearing. I did the same thing on my 7bolt so much fun