Eric

Thanks for the clarification

I was going off of what the 'customer' told me when he brought it to me with symptoms. I hadnt seen any of the receipts, and the guy has 6 other cars so I can assume he was just confused.

Do you mind PM'ing me the shop for my own personal information

Thanks again

Andy

 

Can you guys explain what "cutting" the crank is?

 

When a crank gets damaged, a machine shop can grind the journals down up to .25 mm under sized to clean them up. This is quite common in the industry. You can buy undersized bearings from every manufacturer.

Crankshafts are case hardened in the journal areas making the surface very hard and not easy to wear down. Case hardening treats the surface of the crankshaft and the hardness decreases the further from the surface you get. Grinding crankshafts under size removes a lot of the case hardened material. For high performance applications, an uncut crank is stronger and less likely to fail.

 

Update on the engine.

I pulled the motor out of the car today and disassembled it. It would appear that this motor was an in car rebuild. The balance shafts are still in the motor. The pistons are JE with minor scuffing on the skirts and appear to be in decent condition. The rods are Eagle and are cut for narrow and wide bearing tangs which I have never seen in an Eagle. The rod bearings are in decent shape with minor contamination marks. They are factory Mitsu bearings. The front thrust bearing (one that takes the abuse of the clutch) is toast. Most of it is in flake form in the pan and inside the oil pickup. What is left was very deformed and actually working its way around the journal into the main bearing area. The second thrust bearing fell out and ended up in the oil pan. The thrust bearings are also factory Mitsu bearings. The center main bearing is delaminated and nearly spun. The rest of the mains are showing signs of contamination with copper showing in the center of the bearing where the oil feeds in. The mains are also factory Mitsu bearings.

There is no obvious sign as to what caused the issue. The odd part of the whole build is that there are factory bearings in the motor. For an in car rebuild, you would assume that at the minimum, the rod bearings would be upgraded.

 

So your saying factory bearings, rod or main, are not good bearings? Why do some shops tend to use them in their high performance builds with no problems?

 

I am not saying that factory bearings are bad or that they wont work. There are however better choices than the factory bearings when it comes to high performance high horsepower applications.

 

Sweet

Good info to know......I havent heard from the Doc so I'm not sure which route he is planning on taking. I'm assuming he's going to want a built 2.0 setup....

 

careful with that crankwalk. not good

 

No they just **** rod bearings lol

 

whats the best method putting the stock thrust bearing in??? cant figure it out

 

so the title is misleading, it was a built engine with a cut or stock bottom end. how can you say it is crankwalk. it is modified and not related to the stock internals. please delete thread.