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JMPH 05-11-2011 07:29 AM

Does anyone have 07 or 08- 525, 600's or 700's with header problems

Thanks Joe

ACTIVESHACK 05-11-2011 07:47 AM


Originally Posted by JMPH (Post 3400178)
Does anyone have 07 or 08- 525, 600's or 700's with header problems

Thanks Joe

Just replaced both sets of mine on 07 525's. All 4 of the old ones were leaking and one of those had been replaced previously.

JMPH 05-11-2011 08:01 AM

Wow!! I thought problem went away in 05 - 06.
That's not right.

Thanks for reply

Dean Ferry 05-11-2011 08:43 AM


Originally Posted by ACTIVESHACK (Post 3400196)
Just replaced both sets of mine on 07 525's. All 4 of the old ones were leaking and one of those had been replaced previously.

AS,
MAN that is just crazy!:angry-smiley-038: I'm assuming that you have talked with "Smarty" here on OSO about this.....
Good luck.
Dean

REDS32 05-11-2011 11:06 AM

I think the Etops are the stronger of the two I run in rough water all the time had them on two boats.I run with my friends who have newer boats the swept headers on two of my friends boats have had problems one small one bad. But down here in FL we run them like we stole them. All the hard bouncing I think is what brakes them. Just my thoughts. I'm not a pro but know people who've work on race boats for a long time. I've been in the shops and seen a bad header trash alot of motors .

ACTIVESHACK 05-11-2011 12:02 PM


Originally Posted by Dean Ferry (Post 3400252)
I'm assuming that you have talked with "Smarty" here on OSO about this.....
Good luck.
Dean

Sure have :grinser010:

KEPP 05-11-2011 01:10 PM


Originally Posted by Dave M (Post 3396520)
Got a few spare hours? Do a search on CMI headers, this issue has been discussed in nausium.

Short answer is that you want the headers that the outer tubes are not directly welded to the flanges. You should see a 1/4" gap.

The "Gap" as commonly referred to is what CMI call's their Cool Collar it is a patented design that they chose to switch to. You will find in the case of the 525,600 and 700 Merc engine header failures they have nearly nothing to do with flange failures but that of rotting out internally. As so many different posts have referred to.

We sell both the CMI GEN-X header http://www.keitheickert.com/p-14849-...0-engines.aspx

and the New Hardin Hurricane Lite as direct replacement headers for this application to reference two different styles. http://www.keitheickert.com/p-15770-...mi-flange.aspx

sunsation96 05-11-2011 01:15 PM

Is this thread heading to a Mod clean up also? The Merc CMI threads seem to go MIA, sucks to see so many members here getting stuck paying the bill for a bad parts.

PARADOX 05-11-2011 03:14 PM


Originally Posted by ACTIVESHACK (Post 3400196)
Just replaced both sets of mine on 07 525's. All 4 of the old ones were leaking and one of those had been replaced previously.

LMAO. Ditto bud.... I don't want to get into a long CMI discussion, the last one I started got deleted.
The short version; Motor, drives, etc. 2007, rigged in 2008 on new Avanti hull in Spring, 2008, During rigging we noticed one header had pit holes on the lower distribution track. Replaced by Merc, under warranty. Boat, motor, drives are in, boat running great, 2008-2009. Checking routine compression late 2009; problems. ALL headers were leaking, including the new, replaced one. Engines had valve issues. Luckily nothing major. Engine uppers, (valves springs etc) redone. Headers shipped to CMI, CMI confirmed the leaks, fixed them (I Paid shipping, paid for polishing which was not done by CMI, etc.). After gezzillions of $'s boat back in good running order. Late 2010 routine check. Two headers are leaking again. Engines were riligiously flushed, headers drained, etc. Motor dino. AWSOME, 580HP, I got lucky again, no motor issues. Headers fixed, purchased new, boat running great.
CMI diplomatically told me to go fly a kite.
I went kite flying and came up with a conceptual design that will ELIMINATE ALL leaking header issues. Plans are in the works, will post on this soon, but I think I got the issues solved. :) Out of the box thinking, but it works, fab shopes are making proto type. Warranty: LIFE TIME. well ok not life time, but 10 yrs. is good enough, and even if your X wife puts a hack saw to it, it won't hurt the motors. Any interest? :evilb:

eddie 05-11-2011 04:00 PM

1 Attachment(s)

Originally Posted by KEPP (Post 3400515)
The "Gap" as commonly referred to is what CMI call's their Cool Collar it is a patented design that they chose to switch to.


Picture of "the gap" thought it might help out. I'm a visual type of guy. :drink:


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