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Re: COMPRESSION LEAK AT SPARK PLUG SEAT

Just a thought that using the prechamber disc probably will not maintain the gasket surface true flat and perpendicular to the centerline of the spark plug.  I would use the spark plug tool since it will work to keep the gasket surface flat and perpendicular to the centerline.  This will help in getting a seal with the spark plug gasket.  I don't believe that you will take too much material off the seat to create a problem at this time.

 

Best Regards,

Al Hunt

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Re: COMPRESSION LEAK AT SPARK PLUG SEAT

Thanks for the reply AIH.  I did have the plug thread cleaner tool, but was reluctant to use it at this point so we cut down a pre-chamber cleaning disc and it worked very good. I'm in a must run situation with this unit for the next 3 months so I did not want to be removing metal if without having tried it before. I'm going to have the mechanics make sure to plug tube is clean before removing the plugs and then check the seat for cleanliness before installation.        Thanks, Lee

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Re: COMPRESSION LEAK AT SPARK PLUG SEAT

I haven't heard that this is a wide spread issue.  Cat recommends using the Cat 9U7511 spark plug thread cleaner if the threads or the gasket surface is not in good shape.  The thread cleaner cleans the threads while the spring tensioned scraper portion resurfaces the gasket surface to ensure good contact.  Cat does not recommend using the tool unless necessary as it does remove material both in the threads and on the gasket contact area.  Performing this procedure should resolve your problem unless the cylinder head gasket seat area is damaged severely.  Be sure to properly torque the spark plug at installation; 50 ft/lbs torque, gap is 0.011".  This would require replacing the head.  At 22,000 hours, you are nearing time for a top end; probably by 30,000 hours as an estimate.

 

Hope this helps resolve your problem.

 

Best Regards,

Al Hunt

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COMPRESSION LEAK AT SPARK PLUG SEAT

  G3608 engine with 22,000 hrs.  We are having compression leaks at the spark plug seat. Always new spark plug gaskets installed when servicing plugs. Has anyone had this problem?   Thanks, Lee