525 header question......

CMI has their new Generation X ?? replacement HP525 headers up for sale now.
Heard they were to solve the Mercury/CMI HP525 header problems? Will be interesting to see how they hold up.

Best Regards,
Ray @ Raylar
 
CMI has their new Generation X ?? replacement HP525 headers up for sale now.
Heard they were to solve the Mercury/CMI HP525 header problems? Will be interesting to see how they hold up.

Best Regards,
Ray @ Raylar


They are on the way but not currently for sale......
 
If I were one of the people who got stuck with their original headers I'd be loathe to go back to the same company for an upgrade.

The head bolt pattern is unique so apparently no one has come up with their own design. Combined with with a sh!tty original design, CMI owns the market for these headers.
 
Stainless Marine told me they have a complete jig they they can ship that allows you to safely drill the heads for a regular header. If you go Stainless Marine you may lose a little power but their stuff is the most durable
Steve
 
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Mercury mandated the design.

...against CMI's advice.

But they supposedly now have a fix? Couldn't have been done from the outset? It's still a CMI product, nobody cares when they have to shell out thousands to replace the original header with an equally defective one. The internal bickering between Merc and CMI, if it does exist, is of no interest to the affected party.

If they put out a defective product then it's their reputation that will take a hit, if they did it to profit at expense of their customers then shame on them. I will go out of my way not to replace an exhaust system on my next boat with a CMI product because I've witnessed the issues with my friends' boats. I know several others that will do the same.
 
...The internal bickering between Merc and CMI..is of no interest to the affected party...

Agreed. But Mercury is as much or more to blame than CMI. If CMI had refused to build what Mercury specified, Mercury would have gotten Stellings or someone else to build exactly the same part. Therefore, Mercury got what they wanted. Mercury is also the company that specified a cylinder head design that prevents its customers from using another off-the-shelf exhaust system.

If they put out a defective product then it's their reputation that will take a hit, if they did it to profit at expense of their customers then shame on them. I will go out of my way not to replace an exhaust system on my next boat with a CMI product because I've witnessed the issues with my friends' boats. I know several others that will do the same.

Guilt by association. CMI's customer was Mercury, not the engine buyers. The engine buyers are Mercury's customers. Mercury brags to no end about controlling everything that goes on their engines. With that authority comes responsibility for the outcome. If 525's were failing pulleys or pistons, would people be pissed at the pulley/piston manufacturer?

I'm sympathetic to the people facing the 525 header issues.

At least CMI appears to brave enough want to offer the header that they (CMI) wanted to build in the first place. If Stellings offers a replacement, and Stainless Marine offers tooling to convert to standard bolt pattern, the free-market system is providing alternatives. It's a shame that it had to come to this, though.
 
Agreed. But Mercury is as much or more to blame than CMI. If CMI had refused to build what Mercury specified, Mercury would have gotten Stellings or someone else to build exactly the same part. Therefore, Mercury got what they wanted. Mercury is also the company that specified a cylinder head design that prevents its customers from using another off-the-shelf exhaust system.

If true then CMI put profits and production over quality...period. They could have elected not to manufacture a defective product. Nobody forced them to make these headers. Furthermore as a business owner myself I'll not compromise my work, my reputation and ethos will make me turn down work that I can't back up. I'd expect the same of any product I purchase.

Guilt by association.

It's guilt by defective product that was made by CMI.


At least CMI appears to brave enough want to offer the header that they (CMI) wanted to build in the first place. If Stellings offers a replacement, and Stainless Marine offers tooling to convert to standard bolt pattern, the free-market system is providing alternatives. It's a shame that it had to come to this, though.

I don't see it as being brave, I see it as them taking a pounding in the market as their reputation is being tarnished. It could be a reaction to many complaints and if they did have prior knowledge as you suggest it could be a stop-gap to possible legal issues. A simple subpoena and the discovery of emails between CMI and Merc about a possible defective product being distributed would not be good for either company if all is as you allege. As to my initial point, if they have the fix, it should have been done from the outset or not produced. It looks to me as if CMI profited at the expense of their quality, reputation, and ultimate customers. To hide behind Merc is merely just another way of profiteering.
 
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I understand your position 100%, Indy. I guess that my point is: Toyota is taking the responsibility for gas pedals that they specified, but did not make. I feel that Mercury should do the same.

I would suspect that CMI will stand its ground when faced with the same situation in the future.

In the meantime, hopefully the alternatives will solve the problem.
 
I understand your position 100%, Indy. I guess that my point is: Toyota is taking the responsibility for gas pedals that they specified, but did not make. I feel that Mercury should do the same.

Understood...it takes two to tango and they did a bad job on this one.
 
Both my friend and I have 525's with the original headers from 2004. Neither one of us has had a problem yet. I will pressure test this season, but I think that the header failure rate has to be a salt water issue. Anyhow, it would be nice to know how much the replacements would cost when needed.
 
Both my friend and I have 525's with the original headers from 2004. Neither one of us has had a problem yet. I will pressure test this season, but I think that the header failure rate has to be a salt water issue. Anyhow, it would be nice to know how much the replacements would cost when needed.

Tech at CMI said it is time that kills the headers rather than hours....... The other helpful hint was to never overheat them (bad impellers/clogged strainers). Seems they last significantly longer with no overheating.

How many hours do you have on that 36 now?
 
I have about 180 hours as of right now. Every year I do new impellers and housings at the beginning of the season.
 
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