CMI headers. Are they fixable?
 

I did a whole lot of searching on here regarding CMI headers. Well I'm one of the lucky ones!!!! They leak!! I saw there were many ways to pressure test them and I chose air. Easiest for me. I WAS going to put it in a bucket of water to watch for air bubbles but that wasn't necessary. It is leaking on the rear exhaust outlet(where the exhaust exits the head and enters the header). There is a crack right where the flange to bolt it to the head is welded on, on the inside of the tube tho, not the outside. My question is......is it fixable? If it is, just because that gets sealed up doesn't mean there isn't a leak somewhere else correct? Also what would be my best route if they are garbage? The motor needs a refresh this winter so now I'm on a budget. What would it cost to replace this exhaust with something. I know nothing is cheap

You can send them to CMI and they can fix it and inspect them. I happen to have an amazing welder near me who took care of my leak. Haven't had another problem yet but will check them every year. That's a very common spot for them to crack.

I didn't know that was the common spot. I have a good welder a town over. Myself and others have used them for various things and always had good luck. I guess I'll try that being one is good (it's in a bucket of water with 40 psi in it right now). Wasn't sure if that was even feasible. Thanks

Some of the older ones get eaten up from salt use and ethanol will eat the stainless, the later ones with cool collar seem to be ok, Id look at Stainless marine for a replacement

You're not one of "the lucky ones" - you're one of the vast, Vast VAST majority whose CMI's either do leak or are one day going to.

Just send them to CMI. They test them and fix them for $150/motor I believe (not including shipping). I'ts simple and painless.

The best fix would be throw them in the scrape pile and buy Stainless Marine done!!!!!

Well I dropped them at a welder who has done work for me in the past. See how it works out. craney-that is what I have been reading but unfortunately with the motor needing a refresh this winter, buying a house (sold the last one) getting married, and planing for kids........I guess you get the point. What do they run anyways?

Throw them out! I lost two motors (port & starboard) because of leaky CMIs. They're great if you've got disposable income and can replace them every 2 seasons as part of your maintenance checklist.

What is the cool collar you speak of. It is listed on their site on the new headers, but no pics of it.

The cool collar design has been around for a very long time. My 2004 CMI's had a cool collar.
Its a wider area of cooling on the outside header wall about an inch from the flange that bolts to the head.

Ok, got it back from the welder. Looks great and THAT spot is sealed. BTW my other header is fine. Sooooooo is there another spot where these things typically leak from? I can't remove the tail pipe section to get a better look. They are siliconed and clamped on. I loosened the clamp and tried to break it free but no such luck. Any suggestion? So far this cost me only 30 bucks in fittings to rig up to the compressor and 80 bucks to have the pipe welded. I would like to see if the other leak is accessible for a weld. I know some guys say chuck these in the garbage but I can't afford a new set anytime soon. House, wedding....motor refresh this winter....priorities (not my choice of priority order!!!!)

I can get it to rotate/twist. Am I missing something on pulling it apart

Disregard the last post, sometimes you need to walk away from something for a couple minutes and come back to it. It's pretty easy to separate!

My '07 vintage CMIs have been trouble free. They've never seen salt water though. I pressure test them the way you did.

I put a water crossover across back of engine connecting both exhaust water passages together. have a ball valve in 1 hose down low from t-stat housing to manifold. when I shut off the engine, I flip open the valve. no water left above the exhaust ports while sitting...