I have burned through 3 sets of rubber bellows/connectors since '07.
I have Dana Marine exhaust with short risers and Corsa switchable
diverters. The problem part is the rubber bellow/connector that
attaches the aluminum riser to the SS Corsa diverter.
I was told from the start that the Dana risers had a slightly
different angle to them than my stock Merc risers. I just figured that
if the rubber connectors were centered up I would be OK. Anyone
have this problem? Anyone find a solution to this problem? Water flow
seems good and I rarely find sand when I flush the system out during
the Summer. Can the water outlets in the risers get plugged up with
sand? Do I need to poke around with a wire? I did run the engine
with the rubbers off for a few seconds to see if I was getting good
water flow out of the risers. I did have water spray. How much seems
to be debatable. Ideas?

You may want to try the silicone hose from Trident. It will hold about an additional 100 deg. over rubber hose.
Eddie

If this a Dana 496 header kit as they have a drain valve lever piece on them that must be in the closed position or not enough water will go through the header and can overheat them sometimes along with any rubber hoses.

Best Regards,
Ray @ Raylar

Engine is a stock 502 MPI.

Yes I did think about the hi-temp silicone hose. I just want to be sure
that the cause is not my fault(install) before I proceed.

O.K. I guess I'm the only one with a 454/502 based engine that has
this problem? Good to know.

Perhaps the SS risers don't have this issue.

Yes it happend to me a couple of years ago on one of my engines and I posted the same as you.
I had the angle a little off and it burnt a hole. I just took it apart and made sure the angle was straight.

Do a search with my username and you will find it.

Also two of the best in the business have spoken, so you might want to listen to what they have to say.

You're not the only one. Wondering how to deal with this on an install with Corsa Q&Q and Stainless Marine. The SM risers are as close to OEM as they get I imagine, but they still exit almost two inches higher than where the diverters are. Already had to trim the diverter inlets to fit the risers, now trying to decide whether those stock rubber "couplings" can be trimmed to fit, or whether to go with the silicone hose. The other problem is to get the diverters high enough to match up with the risers, the downpipe barely sits in the y-pipe coupling. Glad it's a single engine, that silicone hose in 4" adds up quick...

i had this exact issue on my 454 with the danas, always the starboard side too, alignment was good and went through about 2 hoses a season, called dana marine and they sent me 2 stainless sleeves that inserted inside the hose about 6in long but they would not stay against the riser, slid back towards tips, mine always burnt bout 2-3 inches from the riser, my final fix was bought 4" stainless pipe from auto store and only used the rubber hoses as a connector, i cut them to fit exactly between risers and tips, no corsa, and removed the tips to install rubber hoses, may not be what others would do but it lasted 3 full summers without any issue what so ever, also "thickened" up the sound alittle

So did alignment fix your problems??