Xlint,

With the quality of those welds, I'd guess they know what they're doing. With that in mind.... I have a guy with a weld station set up in my shop that also knows what he's doing (he welds stainless and Inconel 10hrs a day, 5 days a week at his day job). From what he tells me, they get full penetration through the wall thickness. They will have either set a small gap between the two pieces being joined and will have filled that gap completely with filler material, or just fused the two pieces together, with some extra filler to bridge between the two pieces. They don't just glue them together with a bead of weld. You SHOULD have no gap on the inside whatsoever.

Thanks. Brad.

Griff, Xlint,

Most likely not really a secret, but I have a technique, if you will, where I come off plane, then give the throttle a small bump just before the prop wake hits the transom. You can feel it lift the transom just a bit, then I come back to idle. This primarily serves to make sure that prop wake doesn't wash over my swim deck and find its way into the engine bay through the vents, but it also puts some exhaust pressure in the tubes while the prop wake tries to fill them up. Just a thought for those concerned with either issue.

Thanks. Brad.

Thanks for the replies guys.

Definitely a "lip" on the inside. Some are better than others. (nothing real bad)

I thought about filling them with something like JB Weld and hand sanding to smooth it out. My fear is the JB may break loose and disappear with expansion/contraction. I was actually considering using high temp silicone in the seams.

Thanks for the heads up on the TCM rings.

My tips are high enough to not worry too much about wake entering them. Just felt a second set of flaps was good insurance. Those in-lines look to be a bit restrictive, so if not needed, I'll pass.

Xlint,

Kinda surprising, considering the quality of the welds. Probably the difference between hand TIG and automated. You might be better off filing the lip away. I wouldn't think you'd have a lip anywhere but on an inside corner weld (outside corner on the inside), so getting the file on it wouldn't be difficult, even if time consuming. As long as you don't get into the filler material, you should be fine. Personally, I wouldn't put anything in there that could find its way loose. If I had to choose, I'd just leave the lip. It is 316 stainless, right?

Thanks. Brad.

304 S.S.

I'm going to knock down any edge inside the pipe with a Dremel. I just wanted to fill the "seam" so water doesn't sit in there was my thought process.