Tips on header to tail leak
 

CMI's with bravo tails.

I've never EVER had this problem - anyone have any tips on solving this? I've broken 3 T-bolts in the clamp over-tightening them.

The fiber gaskets are relatively new ( one season ). Just keep getting a couple drips and it's driving me nuts. I don't have the rope style, I have the flat flange style with the V-clamp.

Are you sure you don't have a crack in the collector? You shouldn't be seeing any water where the tails and headers mate. I typically use a gasket but also with some Ultra Black on both sides and then run a bead around the entire flange to seal it before putting the band clamp on; don't want any vacuum pulling water from the outside in.

yep ^^^ water at that joint is not good, if your jumper tubes ( hoses )are tight you may have a crack

Jesus I hope not. I guess I'll have to look. Do they usually leak at the inside?

I wish now I wouldn't have put that other motor in yesterday - I think it might be brutal getting that header off with both motors in the boat........

I don't know about "usually", but they definitely can. The tailpipe flange is welded to the collector, so it is absolutely possible to get a pin hole or worse in that weld and if you do, the water will seep out of it. Simple pressure test will show if it does. I had a leak in that very spot on one of my center engine headers. As I said before, you should not have any water at the header/tailpipe connection assuming your jumper hoses are connected and tight.

Pressure test everything prior to running the boat again...30-35 psi should be sufficient.

Good luck pressure testing the tails tho. It's not easy feat. I used an inflatable plug which didn't really work that well. The inflatable ball kept letting go under pressure.

How much time do you have on the headers? Hate to say it but the welds give up after a while. Corrosion, heat cycling, and vibration kill welds.

I recently sold our set for stainless marine.

Fought this same thing before. You have a leak. Pressure test those headers

What sucks is I had pressure tested them a month or so ago and sent one back to CMI for repair. Looks like I either didn't leave this one on long enough to leak down or it just isn't quite leaking until it heats up a little.

When you put the clamp on sung it up, then take a brass hammer tap the clamp all the way around retighten the clamp again, then repeat as much as needed. This method helps to properly seat the v-clamp all the way around.
Each time you will notice that the clamp becomes a little loose after tapping on it due to the V seating.

If headers checked out okay look at the tailpipe. As 1moses1 said they're very hard to pressure check but you usually can see the cracks down by the flange. I had the same problem on a 525 and kept looking at the header but it was the tail. Tails are much cheaper than headers as well. Good luck!