I just checked out my post in Offshore Only. Com. ~ Forums to see it was still active.
"Hell Yes'' and I thought it was just my problem. To all my DLB friends, please read the replies from all over the U.S. about the CMI Headers, and make your own decision. My goal was to find out what the heck was going on with these Headers. I am aware that parts wear out, thats why we do preventive maintance, but if I would have known about this, I might not be rebuilding both engines. Mercury Racing Spec CMI sporttube header systems built between 2001 and 2006 on the Merc Racing HP525 and 600sci engines and the Merc Racing HP500efi (e-top equipped stainless headers produced between 2000 and 2002.
From what I have been told by Raylar, Merc Racing specified to CMI what material (stainless spec) and what after weld heat treat procedures CMI was to use after the header was welded. (COST CONTOL) very good bean counter definition for make it cost less to us the manufacturer user! The cracking that shows up on most HP500efi, HP525efi and 600sci engines during this period stems from the brinelling of the weld area from welding which basically makes the welds and the surrounding stainless material more brittle and prone to cracking under stress, heat and vibration. The method of welding, the actual welding rod and stainless tube used and the use of or non-use of heat treating after the welding will affect the how the possibility of cracking is controlled and how prevelent it will be. Mercury like any big corporation has management performance incentive job sustaining and pay packages that would be and would have been seriously affected for management if they openly addmitted they had thru their specifications created a large and expensive warranty and damage issue. So what do most managers and corporations do in this type of situation. they go MUM, make it a no talk issue, patch the bleeding wounds wherever they can and hope that time and changes will make the problem disappear with the minimum of financial loss back to those who made the BONEHEAD decision to take the risk of an inferior product. With time when it actually fails will hopefully transfer to the buyer as much as possible thru warranty time lapse and careful "Damage Control"!