Tides sure seal hose routing

[anothernewb]

I'm so close to firing up my 350 mariner for the first time but for the life of me I can't figure out where the second hose for the prop shaft seals go.

Port exhaust riser_____prop seal____prop seal____????

Can any of you fill in the blank. Only one riser has a nipple for the hose to the water seal. I've checked all the manifolds and risers and can't find another.

[Viper]

Should be one on each engine to its own shaft log.

[Ramsport47]

I believe the second one connects the two shaft seals together, in case one water pump fails or water stops flowing for some reason, you still have cooling water running to the second seal

[Viper]

Kenny, by the original post, my take is that he has a line going from port to the seal, then to the next seal, and nowhere from there, but there should be one from each engine.

I haven't had a chance to confirm yet but I seem to recall a Mercruiser bulletin about not hooking up the two seals to each other. If I remember right, this came about as a result of engine water intrusion. The reported faults happened as a result of the following; when heading back to shore on one engine after the other failed to run for one reason or another, water that was discharged from the running engine's exhaust through the dripless shaft seal on that engine's side, would as it was designed, also feed the opposite side that had the failed engine. The issue was that the exhaust water going through the failed engine's shaft seal would carry on through the seal and up to the engine that wasn't running as it would not encounter any water pressure from the non-running engine. Somehow, under the right running conditions, water would enter the exhaust side and run into any cylinder who's exhaust valve was in the open position. Merc's suggestion was to isolate the two seal assemblies by capping of the ports leading to the opposite seal. Maybe someone with a better memory than me can confirm (or deny).

[anothernewb]

Thanks for the info. I still haven't figured it out but Vipers comment makes sense. There is a hose that crosses the two seals together.

Anyone with a 350 Mariner want to take a peek in their engine room and check for me?