Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Boating Discussion (https://www.offshoreonly.com/forums/general-boating-discussion-51/)
-   -   525 Header Failure?? (https://www.offshoreonly.com/forums/general-boating-discussion/159021-525-header-failure.html)

Elite Marine 05-23-2007 10:21 PM

Just remember, the OEM Headers from Mercury are not the same material and specification as the CMI Headers from your CMI Dealer or Distributor.

Unfortunately we can't even sell you 525 Headers. Mercury Dealer part only!!

articfriends 05-24-2007 12:39 AM


Originally Posted by Pantera28-650HP (Post 2138599)
Just remember, the OEM Headers from Mercury are not the same material and specification as the CMI Headers from your CMI Dealer or Distributor.

Unfortunately we can't even sell you 525 Headers. Mercury Dealer part only!!

Are they a different grade of stainless,what grades are the aftermarket vs stock? Smitty

restabr 05-24-2007 08:37 AM

Has anyone thougth about getting a company like JETHOT to coat the inside of the headers. The aviation reference got me thinking about it. For those not familiar, they basically apply a ceramic coating to the inside. They do alot with exhaust manifolds for aircraft engines, they say for better heat disipation. Seems to me like this would prevent salt water from ever touching the metal in the first place.

C.

RonS 05-24-2007 10:31 PM

Anyone try replacing the cmi headers with stellings, if so how have they been holding up???

JROMY 05-24-2007 10:40 PM


Originally Posted by fountain40icbm (Post 2138406)
This is Dan's dad.
Welcome to the CMI club!!!!
I work in aerospace and am fixng CMI headers all the time.
Unlike CMI, we don't let tubes fail at 40,000 feet!
I think we all expected more when we finally had enough money to buy a boat with stainless steel headers!
Right gang!?
Thank goodness for TIG welding!!!!

Ken - I have a sneaking suspicion that mine are probably going to go this summer based on everyone elses experience. Did the TIG welding at least let you finish out the summer before you had to replace all the headers? Is there an alternative to the CMI's? We all spend WAY too much money to have these things fail the way they do. :mad:

cowisl 05-31-2007 11:52 AM

Mine just failed :mad:

restabr 05-31-2007 11:58 AM

So is anyone seeing the failure of the headers being terminal to the engine itself due to water ingestion, or can the failure be caught far enough in advance to not nuke the motor?

OldSchool 05-31-2007 12:00 PM


Originally Posted by RonS (Post 2139904)
Anyone try replacing the cmi headers with stellings, if so how have they been holding up???


They should hold up pretty well considering that they aren't junk like the CMI's are!!!:D

Ted G 05-31-2007 12:44 PM


Originally Posted by restabr (Post 2146362)
So is anyone seeing the failure of the headers being terminal to the engine itself due to water ingestion, or can the failure be caught far enough in advance to not nuke the motor?

If you have a RInda or Merc laptop program there is a cylinder balance test, I caught weak rear cylinders (7 or 8) due to the leaks, however the engines were due for refresh so I don't know how much longer they would have lasted.

cowisl 05-31-2007 01:42 PM

Not sure yet. they are taking the engines out as we speak. Hopefully no damage was done to the block.


All times are GMT -5. The time now is 10:09 PM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.