525 Header Failure??
 

Anyone know anything or got any experience with the headers on 525's failing due to corrosion. I've got one that basically turned to swiss cheese in about a two to three square inch section in the top of one of the tubes. I've heard rumblings that there have been problems with corrosion at other points (flanges) resulting in sea water leaking back into the head/cylinders. The reason for my question is I'm simply wondering if my other three headers are time bombs. At better than 4K a piece I'm not in a hurry to replace, but I certainly don't want to drown one of the motors either.

Thanks in advance.
C.

Salt water,even on immaculately maintained boats like yours ,is not kind to 525 headers. I have a customer in south Fl that has replaced a couple,a customer in Ca that has replaced 2,actually one today,and these were well maintained boats. And unfortunately,most extended warranty programs exclude the exhaust system:(

The new ones they make have a new design. They now have what they call a cool collar. These are better CMI says.
If you have a problem with one odds are you are going to have a problem with the others. We put 4 new ones on a few months ago, better safe than sorry.

CMI"s "Cool Collar" header is not all that new. Are any Mercury Racing's 525's not the "Cool Collar" design?

I know two people with 525s and they both had CMI header issues and they flushed after every run.

How new are they ?

no very early 525's did not have cool collar

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!!!!

My buddy had 8 repairs on 6 headers by 300 hours. Finally bought new ones all the way across, one of those had a leak in a tube on first fire up-sprayed water 3 feet high. They wouldn't even send a new one-made him return the "NEW" one for repair:rolleyes:

I have one of the early 525's and before I bought my boat, the port side was replaced and then last year I had the starboard side let go, but it was fixable. I scored a very slightly used set from Tyler Crockett (mainly freshwater use) this year but I still have my old set. I wouldn't mind picking up some cash for them, but I'm so nervous right now about not having another set. Is there a way to tell if I have the cool collar set?

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

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.

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

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:

Mine just failed :mad:

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?

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

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.

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

How much did it cost to get the headers redone from cmi?

The CMI's don't fail from corrosion, they fail from vibration and heat cycling... They also are prone to failure if the header develops a hot spot. The hot spots are created two ways; first if there's an obstruction (rust chunk etc.), secondly if when they were manufactured the inner pipe is too close to the outer pipe..

Damn CMI's,,,, every week I fire up my engines I worry about these darn things.... I'll be purchasing Stainless Marines next go around... :(

CMI charged 100 dollars for the one fix, plus I had to pay for my shipping up there. They do not guarantee that they can fix it as well, it all depends where the crack is. Mine was easy because it was right where the 4 pipes merge into 1. Right along that weld. For the time being, I'm keeping my second set.

a friend of mine with an 05-06 39 Gun is about ready for his 3rd set...1st ones cracked, gottum warrantied last season and already this season same header, same crack , same place...things that make ya go hmmmm

Best thing to do is drain the water out of the header after every run...so if there's a crack the water doesn't go back into the motor. Sometimes you can catch it, some times you can't...just gotta check them all the time.. :(

I think these are;
http://www.offshoreonly.com/forums/s...ad.php?t=27458

FYI, I think the stainless marine GenIII's are also cheaper than a CMI setup. I think they're somewhere around $3600 complete with tailpipes to your specs.

I've had great luck with KE headers, they are not the eyecandy that CMIs are, BUT I ran a set in Salt water for 7 years, (flushed every time) and they performed AWESOME. Plus they make great power. When I repower the nordic, it will be with either KE's or SM.
Dean

cmi's are prone to crack and leak ido marine work for a living can't tell u how many cmi I had to have repaired or replaced. lee

Sold lots of 525's. Never a failure in freshwater.Lots of failures in saltwater. Go figure,saltwater is the enemy,but you would expect good maintenance would help,apparently not with these headers:(

Man, that's a bummer :mad: What let you know they had gone? I've been told to watch the exhaust for steam, one pipe being a little different than the others, slightest sign of milky oil. Anything else I should be watching for?

Also a rough idle as well because of water dripping back in. That's what clued me in to something being wrong.

Freshwater = Flat

Saltwater= Rough

Anyone that has watched the beginning of the Freeze Frame video where the hatch comes off can see how much those headers flex as the boat pounds. It's really no wonder they fail like they do.

I just lost another motor last week due to the header leaking! Where do you go for different exhaust? I know how CMI stays in business now!

Bernie Is Tony is on his fifth set or 3rd?

I think that GOODT has an extra set lying around. Give him a call!!!:eek: :drink: :evilb:

This is kind of amazing. I'm an automobile dealer and if the products I sold failed like this I'd have a line of attorneys around the building to sue me and the manufacturers I represent. There is something called the Magnuson Moss Act and fitness for a particular purpose in the relm of warranty. I'm not an attorney and doubtless someone else on the board is and is more qualified to state an opinion but this is really kind of silly....or am I the only one that thinks so? God knows I'm not one to cry "LAWYER," but there is a time and place for everything.

You took the words right out of my mouth. I am also the last person to cry "lawyer", but this issue makes you wonder.....

The problem is, we all buy these systems with NO warranty expressed or implied.... If you buy a new merc package and it happens to have the CMI's then you have a shot, otherwise we're up chits creek without a paddle...

But, what we can do is not buy these products anymore and force them to upgrade quality, along with a comperable warranty like one or two of the other manufacturers have... :eureka:

It's funny, a while back someone with money said ; "With all the money we spend, go for the bling." But when it breaks the cash register goes "Ka-Ching!"

I like the Stainless marine Gen III with 5 inch tail pipes. It was these or CMI Big Tubes and they had a higher failure rate.

The noise gave it away. Pulled the plugs out and water came out the number seven cylinder.

So far, I need:
-1 rocker arm
-new rings, bearings, timing set
-1 valve,
-1 piston
-1 push rod

Hopefully no head damage. Got to love used boats!