Rod Bearing Showcase Thread

[davidf]

'03 Coupe, 180k miles. Unknown history. Dug into the rod bearings the day after we drove the car 160 miles home from purchase. One bearing had spun(#3), but it must have JUST spun as no heat discoloration and no damage to rod big end or crank journal. Bearing felt just as tight as others insert into to big end and clearances checked out. We got super lucky.

[Ramage]

When replacing the bearings, is there a more scientific method of measuring the clearances without removing the engine from the car?

As far as I am aware the Plastigauge method is the only feasible way to check your clearance with the engine still mounted.

[ac427]

When replacing the bearings, is there a more scientific method of measuring the clearances without removing the engine from the car?

[0-60motorsports]

My 2004 Vert at 135000km / 83000 miles - I am the third owner having picked it up in 2012 and there is no doubt my car was treated like crap prior to my ownership. The number of half assed repairs and simply wrong things I had to correct in the first 3 years of owership was nuts.

Number 5 definitely spun at least once, given the witness marks on the back of the bearing. Near as I can figure, the tangs kept it from spinning more than a few times since they're still intact. I got incredibly lucky twice: first, that I didn't grenade the entire engine, and second, that nothing blew up after I completely missed those witness marks, threw new OEM bearings in, and buttoned it back up.



Since then, I've put 20,000 km (13,000 miles) on the car and while the very first oil analysis after the replacement showed elevated Copper(12ppm) and Lead(19ppm), the last three reports have come back clean with nothing in the filter and no cold start knocking.

Nice save.

[RockyMtnM3]

Ramage WOW, that is impressive. Glad you got that sorted out!

[Ramage]

My 2004 Vert at 135000km / 83000 miles - I am the third owner having picked it up in 2012 and there is no doubt my car was treated like crap prior to my ownership. The number of half assed repairs and simply wrong things I had to correct in the first 3 years of owership was nuts.

Number 5 definitely spun at least once, given the witness marks on the back of the bearing. Near as I can figure, the tangs kept it from spinning more than a few times since they're still intact. I got incredibly lucky twice: first, that I didn't grenade the entire engine, and second, that nothing blew up after I completely missed those witness marks, threw new OEM bearings in, and buttoned it back up.



Since then, I've put 20,000 km (13,000 miles) on the car and while the very first oil analysis after the replacement showed elevated Copper(12ppm) and Lead(19ppm), the last three reports have come back clean with nothing in the filter and no cold start knocking.

[M3Mino]

Here is mine done around 89K miles with about 15K VF570 supercharger miles on it.

[0-60motorsports]

'06 car, 105k miles on the odometer. Rod bearing history is unknown, I assume they are the originals.

Nicely done at the right time.

[old///MFanatic]

'06 car, 105k miles on the odometer. Rod bearing history is unknown, I assume they are the originals.

True you don't know if anyone replaced before. But I agree that it's unlikely (if that engine is original @105k) that they were replaced already with that wear showing.

[sapote]

'06 car, 105k miles on the odometer. Rod bearing history is unknown, I assume they are the originals.

'06 cars didn't have bearing recall, so these are original, your timing is perfect for a new set.

[nsa]

'06 car, 105k miles on the odometer. Rod bearing history is unknown, I assume they are the originals.

[E46 M3]

showing copper are the top halves. A bit surprised that they worn this much for 67K miles.

Agreed, my old M3 had over 130kmiles and the new owner recently did them and they looked better than mine...

I do know however that previous owner was an exec lady that had a huge commute and seemingly drove it well.

[Consum3r]

Early 2004 build, bearings replaced at 90k



R

[sapote]

picked up my 2003 M3 earlier this year with 176k miles. The original owner had the car from new and never replaced the rod bearings. I decided to replace them within about 100 miles of bringing the car home. These are the originals below.

Bearings looking not bad for 176K. The PO babied it so you have a low wear drivetrain here.

[SpineDoc112]

picked up my 2003 M3 earlier this year with 176k miles. The original owner had the car from new and never replaced the rod bearings. I decided to replace them within about 100 miles of bringing the car home. These are the originals below.