Exhaust Riser Replacement

[Analgesic]

Second big Winter project is a new exhaust riser. Following many posts here, I checked with Catalina Parts and they don't  stock them anymore.  Catalina Direct lists them on their site but I also read about the advantages of a perfect match by having it made locally.  Where would one go to have an exhaust riser made?  Welder, machine shop, mom and pop auto repair shop?  I suspect it is critical to provide a very specific order since this must be a novel job request.  Also, it must be critical to have the right materials used due to the temperatures involved and the highest quality welding as well.  Finally, I noticed an insulating wrap for sale at CD which seemed ridiculously expensive.  I removed a white woven fabric wrap from the old one held in place by wire wrap which I assume must be much cheaper.  Any suggestions?  Thanks
Brian McPhillips 

[KWKloeber]

You don't need to have a welded, one piece riser.  

Many a Catalina riser has been fabricated of threaded black iron pipe and fittings (I would suggest using Schedule 80) or threaded stainless pipe/fittings.  Much easier to measure and tweak as you fit it out, rather than it needing to be perfect from point "A" to point "B" on the first try.  If you have the time and wherewithal, it can be a DIY project and that way use your fabricator's labor charge (boat bucks) for something else.

You don't even need to have the tools to work with 1-1/4" pipe -- a local plumbing shop will supply the parts and cut/thread as you go.  Of course that may mean multiple trips to finish it.  Or bring the old to the shop and have them cut/fit to match it, or of you're good, measure up and get everything cut at once.

Never use galvanized pipe.

For the wrap you can use wrap from Autozone, etc., who also has stainless "zip ties" to secure it onto the riser.

Ken

[Mike and Joanne Stimmler]

When I got mine (stainless) from Catalina parts about 5 years ago, I had to ship them the old one to match and they also wrapped it with the insulating material. Catalina direct may want the same thing and it would be worth a call to find out. From what I understand, the stainless will outlast the black pipe. They normally reuse the same flange unless it's in bad shape. You'll also need a new gasket but get 2. A lot of times the first one gets damaged some how. I actually ordered 3 just in case and I did use the 2nd one but not the 3rd. Good luck.

Mike

[KWKloeber]

Here's a system that replaces our pipe risers and crappy, leak-prone Aqualift mufflers with a Westerbeke water-cooled riser and a top-of-the-line Centek muffler.  I worked with 3 owners (with an XP, and XPB, and a Beta 20 repower) who did all the install DIY.  These pics are on 30s, but naturally scaleable to any vessel.

No heat wrap and engine compartment runs cool with the water-cooled riser.

Just another option...

kk

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[Analgesic]

Thanks for all the good advice.  I already replaced the muffler with a Centek a few years ago.  My exhaust flange is not coming off the old riser after my first efforts last weekend so I'm planning on replacing it. Otherwise, it looks like we have a plan.   Thanks again. 

[KWKloeber]

Thanks for all the good advice.  I already replaced the muffler with a Centek a few years ago.  My exhaust flange is not coming off the old riser after my first efforts last weekend so I'm planning on replacing it. Otherwise, it looks like we have a plan.   Thanks again. 

Brian,

They are usually a bear to get apart.  The XP
     Exhaust flange is p/n 298599 - retail $89.50 - don't pay more than that.
     Gasket is p/n 298600 - retail $3.20
     Upper studs are p/n 12506 - $4.90 x 2
     Lower stud is p/n 298974 - $14.30

Make sure you seal the flange/gaskets well with RTV - otherwise the flange it's prone to leaking coolant from the exhaust manifold/expansion tank past the flange gasket, into the exhaust system.


Cheers,
Ken

[Ron Hill]

Brian : Take a torch and heat it so you can get the flange off the old riser. 

[Analgesic]

Ken,
What is RTV to seal the gasket?  This is not an abbreviation I am familiar with.

[KWKloeber]

Google vag be your best friend! 

Just search on Red RTV.- red is the hi temp - you can buy it online or your auto parts may stock it. K