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Discussion Starter · #1 ·
Over the years these cars are notorious for spinning bearings due to dented oil pans or lack of required services. What I'm looking for is advice and past experiences with people who spun a bearing and rebuilt the engine successfully. I'm not sure how severe of a issue I have in mine but I know bearing has spun. There are some reputable shops such as Pampena and ninja or even Ground zero but idk if its worth sending out if they will say its junk. Am I better off putting in my spare 4bolt? How Much was the costs when you were finished? How much are the machine shop costs? Who built it? Was it a oem build or did you actually build it up? Thanks for the help everyone!
 

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It primarily depends on how badly scored the journals are as a result. You or a competent shop/individual need to teardown and assess. Cutting and using oversized bearings is almost inevitable. Everything needs thoroughly cleaned and/or replaced as well, so the costs do add up.

-sent from my Galaxy Note 9
 

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Discussion Starter · #3 ·
It primarily depends on how badly scored the journals are as a result. You or a competent shop/individual need to teardown and assess. Cutting and using oversized bearings is almost inevitable. Everything needs thoroughly cleaned and/or replaced as well, so the costs do add up.

-sent from my Galaxy Note 9
So when one of our engines is rebuilt and it spins a bearing shortly after, what is usually the cause of that? Perhaps the break in process wasn't done correctly? or just bad engine building?
 

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That could be due to a number of possibilities. Poor assembly and improper clearances are up there, but a poor break-in procedure especially with a sh*tty rich tune and infrequent OCI's can attribute to failure.

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you should read the post in automotive discussions / general/ inside kormex transmission/ post #42 to #46. very insightful of rebuilt engine failure. hope this helps. halo
 

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I used Ray and David to rebuild my engine and I'm very happy with my car so far(about 5 k miles on it). I originally went with a local engine builder who had built a couple of these engines before but that engine didn't last 2000 miles. Don't do what I did.

 

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That could be due to a number of possibilities. Poor assembly and improper clearances are up there, but a poor break-in procedure especially with a sh*tty rich tune and infrequent OCI's can attribute to failure.

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Oci?

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From my own experience, yes it is worth it. In my case a rod bearing spun. Had a quality engine builder go through the block and heads. Machined the crank down, balanced it, and took as little off the cylinder walls as possible (.0035" if I remember right). I flushed out the oil cooler and oil filter housing in the basement sink with degreaser. Replaced the oil pump for good measure.

It's been 30k miles/12 years of pure abuse and adding power. Motor shows no signs of any type of failure. I did take it all back apart after a couple thousand miles for a noise issue, and sent the block back to the machine shop for them to double check. Turned out the forged aluminum pistons are just noisier than I was used to. No problem found.

I think the repeat failures must be from poor engine work or not getting all the metal out of the oiling system.
 
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Over the years these cars are notorious for spinning bearings due to dented oil pans or lack of required services. What I'm looking for is advice and past experiences with people who spun a bearing and rebuilt the engine successfully. I'm not sure how severe of a issue I have in mine but I know bearing has spun. There are some reputable shops such as Pampena and ninja or even Ground zero but idk if its worth sending out if they will say its junk. Am I better off putting in my spare 4bolt? How Much was the costs when you were finished? How much are the machine shop costs? Who built it? Was it a oem build or did you actually build it up? Thanks for the help everyone!
As I have mentioned in other threads Japanese built engines run a very tight clearance and with that being said one should pay close attention to detail.
 

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As I have mentioned in other threads Japanese built engines run a very tight clearance and with that being said one should pay close attention to detail.
Ive rebuilt Japenese sport bike engines... its not terrible... just slow.
LOTS of plasti gauge
 

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Just decided to throw the following info out there for those who may be interested, the secret behind significantly cutting down on the percentage levels of Engine Bearing Failure, especially for high HP modded engines, is having coated bearings such as ACL and Clevite H-Series race bearings, however its fairly hard to find the correct size coated bearings for our vehicles from both of these manufacturers and perhaps others.
For those who do not know what I am referring to, DFL ( dry film lubricant ) is a material that is heat, friction, chemical and anti corrosion resistant and protects the bearing surface from dirt that gets embedded into the surface, which is one of the main reasons for spun bearings other than the lack of lubrication and excessive heat. They may call this coating different names for marketing purposes but its the same stuff also seen on piston skirts. I bought Clevite 77 oversized bearings ( rods and main ) for my turned forged crank and got them DFL coated ( DIY ) and basically turned them into H-Series race bearings.
 

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Just decided to throw the following info out there for those who may be interested, the secret behind significantly cutting down on the percentage levels of Engine Bearing Failure, especially for high HP modded engines, is having coated bearings such as ACL , King and Clevite 77, however its fairly hard to find the correct size coated bearings for our vehicles from both of these manufacturers and perhaps others.
For those who do not know what I am referring to, DFL ( dry film lubricant ) is a material that is heat, friction, anti corrosion resistant with increased lubricity characteristics. It also has excellent embeddability characteristics. They may call this coating different names for marketing purposes but its the same stuff also seen on piston skirts. I bought Clevite 77 tri-metal oversized bearings ( rods and mains ) for my turned forged crank and got them DFL coated ( DIY ).
BTW for King Engine race bearings they call it pMAX black and ACL calls it CT-1.
 
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The H series race bearings have a thicker steel backing and thinner babbit coating. That is why they are stronger. I have never ran coated bearings in anything. I always run the standard off the shelf clevite h series and things have gone very well.

We do have h series bearings in stock, but yes this year it has been hard to keep it that way. The oversized h series mains have been on back order over a year. Standards are in stock.
 
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I believe a lot of time when we have cars with recurrent spun bearings or head gasket issues its because the problem that caused the engine failure in the first place was never addressed, so you are going to keep blowing it up.
 

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I believe a lot of time when we have cars with recurrent spun bearings or head gasket issues its because the problem that caused the engine failure in the first place was never addressed, so you are going to keep blowing it up.
That is 100% correct, I just posted a reply to the exact subject on First startup after rebuild
 

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I believe a lot of time when we have cars with recurrent spun bearings or head gasket issues its because the problem that caused the engine failure in the first place was never addressed, so you are going to keep blowing it up.
Coated bearings is not a solution for a poor build, it is an extra thing you do for your priceless build.
 

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The H series race bearings have a thicker steel backing and thinner babbit coating. That is why they are stronger. I have never ran coated bearings in anything. I always run the standard off the shelf clevite h series and things have gone very well.

We do have h series bearings in stock, but yes this year it has been hard to keep it that way. The oversized h series mains have been on back order over a year. Standards are in stock.
AKA tri-metal
 

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As I have mentioned in other threads Japanese built engines run a very tight clearance and with that being said one should pay close attention to detail.
Not even with these cars... terrible blanket statement 🤦‍♂️ factory ring gaps' range are loose as hell. Some will even say the specified upper limit for main clearance is too especially with performance/power in mind. Like anything else, one should build and plan for the intended goal and application, period.

-sent from my Galaxy Note 9
 
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