Catalyst housing for my Rotax 1503 size 250

[jgiovino]

... if I ever need service for this same issue ...

I would recommend being proactive and not to wait until it fails.
I hear from other threads on this forum that this is mostly for te grey cats and not the black ones.
I just took mine out and its a mess.
Since the O-ring seals failed, water got between the S.S bolt and aluminum threads.
I have to torch each and every bolt several times to get the bolt to back out of the aluminum flange without destroying the the housing.
Whoever designed this housing failed by not through-bolting it.
Once the seal fails, and it will, gravity brings the water straight down to the exhaust manifold and into the heads.
There is no riser to prevent water from backing into the manifold.


Check out the cost on the parts for repair:

EXHAUST SYSTEM - SINGLE MODELS, WITH CATALYST - AA Powertrain 250 440000AAA | Crowley Marine

View parts diagrams and shop online for EXHAUST SYSTEM - SINGLE MODELS, WITH CATALYST parts, AA Powertrain 250 440000AAA. Offering discount prices on OEM parts for over 50 years. FAST $4.95 shipping available.

www.crowleymarine.com

No wonder why BRP is not honoring its recall.

 

[ChrisM]

It's also something that the dealer, or any dealer will not fix unless there is evidence of the issue, IE: fault code or similar. I don't have any faults, or performance issues so far.
I could voluntarily replace the seals I suppose, but it's my understanding that an O2 sensor code will be present if the failure happens.

 

[Nmoore7]

Does anyone have the part number for the seals? Or anyone have a proven bypass of the cats all together?

 

[Jmorash]

a Quick Bump to This thread.

I too Threw a Few O2 Sensor Codes. Dealership was to Busy to take my Boat. So i removed the Catalyst Housing, and Purchased a Large ultra Sonic Cleaners.

I also used the Links above to Order New Sealers for the Catalyst Housing, and new Bosch O2 Sensors for Up and Down stream Locations.

Here is the Break Down for any of those going through this in the Future

All that was Needed was a 6mm Ball Socket Allen, and 12/11mm Wrench, a 10 MM Socket, and a 1/4 socket to remove hose clamps.


I seperated all the parts, and will ultasonic clean all of them, and then re assemble with new gaskets and Bosch O2 sensors