Offshoreonly.com - 525 header issues?

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There is a difference between the CMI headers and the Merc ones. Even though they look the same are made at CMI there is a very important difference. The Merc headers are not heat treated after production. This makes them more prone to cracking. You can thank Merc for being too cheap to have them made correctly and then charging you 3x the price for an inferior product!

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Originally Posted by thirdchildhood (Post 3614252)

Where did you see that?

did not see it! heard it with me own two ears from mercury racing on tuesday.

Quote:

Originally Posted by BONDO10 (Post 3612614)

I'm sure I will get attacked for this,but my 2004 382 Fastech with 525's has the original CMI's it left the factory with.Pressure tested them last year,and all is good. I am going to replace them this year with GEN X's,for simple fact I don't have problems, and don't want any. We replace water pumps,belt,and hoses. All water/cooling related parts before they fail,why not headers? They are not cheap,but new 525's aren't either. Watch the 2 you-tube videos CMI has out.Very informative.It's all about water flow,not so much pressure.Everything has a life span.My boat has 240 hours and 8 years on it. I think the headers held up well. I have silent choice as well,and use it quite often. I also boat in salt water.Boat is lift kept and flushed 10 minutes a side. One thing CMI talks about is not to raise rpm's above idle on flush.A standard garden hose usually doesn't have the proper flow to keep up with cooling the headers above idle.

Good videos, thanks. I always get nervous flushing because even though I have decent city water pressure, the top port tube gets hot first. At least now I know why. Good informaton on the water pumps too.

Quote:

Originally Posted by SippyRat (Post 3614432)

did not see it! heard it with me own two ears from mercury racing on tuesday.

Well lots of us are running it and the Mercury Racing service manual says it is good to 2,500 rpm only (I believe). If it voided the warranty I don't know why it would be in their shop manual. Maybe the person who told you that did not know better....

Mercury Racing told me not to use silent choice at all on a 525. My engine was out of warranty so they told me, it's your engine so you can do what you want..... I don't use it.

Why do boat manufactures install silent choice if Merc does not approve of it? Is this notice something new from Merc? Never read anything in Merc's operator manual with a new boat that stated not to use silent choice or we'll void your warranty. Can anyone scan and post this info bullentin or is this just hear-say?

Quote:

Originally Posted by thirdchildhood (Post 3614552)

the warranty is only one measly year. maybe mercury wants to give some guidelines for those who choose to run silent choice after the warranty period or maybe the service manual is referring to only the early years when mercury still used their original silent choice. i don't know...... bolting on or altering pretty much any component that is not a merc part will void the warranty. what i am hearing from some is with the state of the economy merc is tightening any and all loose ends that could potentially cost them money. they are much stricter on the factories then ever.

This is right from the 525 installation manual.

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Originally Posted by JTeam (Post 3615032)

This is right from the 525 installation manual.

thanks

Quote:

Originally Posted by JTeam (Post 3615032)

This is right from the 525 installation manual.

thanks a lot! do you happen to know what year this was printed?

this backs up my guess in my last post. they are basically saying "we don't recommend it, it will void warranty but if you do decide to do it this is how it should be done"