C55 crankshaft damage
Super Member
Joined: Jun 2008
Posts: 855
Likes: 1
2010 C63
Whatever caused your crank to become damaged should be investigated. If you throw in a new crank, it's likely the problem is going to happen again.
Also, I've had many race cars, turbo, nos, etc and have never actually seen a "bent" crankshaft. If this is actually the case, the shaft would no longer turn in the motor. I'm not sure what your mechanic was actually talking about but the only possible damage that I can think of would be journal damage. this is easily fixed with a hard weld and grinding. Most machine shops can do it. there is also a nitrite coating on the crank which prevents the journals from being damaged in the first place, so I'm surprised you got this diagnosis.
Me, I abuse the heck out of my car. 143,000 miles now and not any major issues. I also spray 100-125 shot nos and I have a tune. I believe my tranny will fail before the engine ever does.
Good luck!
-Mike
Also, I've had many race cars, turbo, nos, etc and have never actually seen a "bent" crankshaft. If this is actually the case, the shaft would no longer turn in the motor. I'm not sure what your mechanic was actually talking about but the only possible damage that I can think of would be journal damage. this is easily fixed with a hard weld and grinding. Most machine shops can do it. there is also a nitrite coating on the crank which prevents the journals from being damaged in the first place, so I'm surprised you got this diagnosis.
Me, I abuse the heck out of my car. 143,000 miles now and not any major issues. I also spray 100-125 shot nos and I have a tune. I believe my tranny will fail before the engine ever does.
Good luck!
-Mike
Thread Starter
Newbie
Joined: Jul 2011
Posts: 13
Likes: 0
The car could be driven it's just the engine knock...so I assume the crank was not that seriously bent. Now the current problem is the bearings. No one seems to know what size/thickness they should be because it sounds that no two c55's are alike. There are three different sizes available and sounds like they are color matching.
Member
Joined: Aug 2010
Posts: 107
Likes: 5
From: New Orleans, La.
2009 gmc sierra 1500, 2005 C55 AMG, 2007 SL55 AMG.
Have the machine shop take a look at line boring the journals with the new crank they should be able to measure the bearing size. ACL bearings are great! Also check this out, I am also very doubtful the crank is bent read this link my be helpful.
http://mgaguru.com/mgtech/engine/cs107.htm
Have another shop check the crank for balance, should only be scared.
just my two cents
http://mgaguru.com/mgtech/engine/cs107.htm
Have another shop check the crank for balance, should only be scared.
just my two cents
Last edited by Ducatic230; Jul 18, 2011 at 11:07 PM. Reason: grammer
Super Member
Joined: Jun 2008
Posts: 855
Likes: 1
2010 C63
The bearing size needs to be looked up. There are markings on each journal and also on each main cap. These indicate the size of the journals and mains and you determine bearing size from that. If you're getting a new crank, which seems unnecessary, the journals need to be measured as well as the mains so you can get the correct bearings.
