Hi, Tom.

Unfortunately this link doesn't show how long the hose is. I need it to be at least 5". (I suppose I could call them.)

Most of the links I've found on the 2" ID hoses show a 3" length, which is too short.

If it is too long, obviously I could cut it down to size.

New idea: I spoke with the sales rep at [url]www.boostcontroller.com[/url], who said that they could custom-make me a 5" STRAIGHT high-temp silicone hose, and at a reasonable price.

So the question then becomes: Why does this need to be a "hump" hose? What's the harm in it being a straight hose?

Note that the original hose is a straight steel-wire-reinforced rubber hose.

[QUOTE=caprice 1050;10268]The riser can not be moved and the engine can not be moved. [/QUOTE]

?? The riser can be moved. You just unscrew the pipe union, or at least, that's what they used on my 1984 MK1.

Stu, I just called Trident from the google search. Yes, they have it! Thanks.

It's 2" ID and 6" long, but I can cut it down to 5" of course.

You have to order these through one of their distributors (shown on their website).

I will let you all know the results of this, i.e. final part number and such.

Chris, if you are in salt water, you probably don't want to do what I did. I'm in fresh water and there is very little corrosion on my boat, even after all these years.

You are probably better off to get the new exhaust riser from Catalina Direct and I believe the procedure for that has already been documented on this website. (Someone correct me if I'm wrong.)

If, after Tom's comment about the vibration, you still want to try this, let me know and I'll document as best I can.

Chris, there is (at least) one good article on this in the very first jibsheet:

[url]http://www.c36ia.com/files/C36_E_Mag_Jan_08%20-%20no%20tech.pdf[/url]

A couple of things the article doesn't talk about:

1. How to unscrew the forward teak bulkhead (over the engine attached to the stairs) and the rear teak shelf (over the transmission).

The first thing I did was find all the screws that hold the teak bulkhead to the cabin fiberglass bulkhead. They are hard to see because they are covered with teak plugs. I first drilled out tiny holes at the edge of the plug circle and then chiseled out the plugs with a hammer and flat-head screwdriver. After removing the screws, I just pulled the bulkhead away from the wall. It was sticky (coz it was a good cabinetry fit) but it came out no problem.

After I removed the teak bulkhead, the exhaust riser was visible. Also the screws for the rear teak shelf (in the aft cabin over the transmission) were now visible. (Ah-ha! Before I learned that, I was scratching my head over how to get that #$!* thing out!) There are a few screws on the starboard side that also have the teak plugs covering them. Same procedure there. Once that is done, I was able to easily pull the rear teak shelf away from the riser. It was now fully exposed where I could easily work on the riser itself.

2. How to unscrew the pipe "union". The pipe union threads into the mixing elbow. On mine, the pipe union had broken away from the elbow, probably due to the vibration over so many years...

...but the other side of the pipe union (where it actually "unions" to another pipe) was still screwed in ok. I sprayed the threads with PB Blaster (from Home Depot), let it sit for a few minutes, and then used two pipe wrenches (largest I could buy at Home Depot), one wrench on the nut and the other wrench on the pipe itself to unscrew the port pipe section. As hard as I could, I pulled up on the starboard wrench with my hands while pushing down on the port pipe wrench with my foot. My thinking was that the counter-forces would balance out and not bend (or break) the still-attached pipe sections or the engine itself. This worked and the pipe came unstuck. When it felt like it was free of all the threads, I hit it with a hammer (starboard to port) and it came out of the union. (Whew! It was break time for a Coke.)

That's where I am now. All parts are ordered. If they all work, I will post them and where I got them. If not, I'll order others and post those and the install issues I encounter.

Ok, after several weeks of waiting for ordered parts, I have this job completed. No more smelly diesel fumes in the cabin. Happy times! :-)

I have pics and part ordering details. Note that I used the orig exhaust mixing elbow, NOT the new custom one available from Catalina Direct.

Let me know if/how you want me to present this to the group.

Will do. What does it need to be, a Word document?

Gary: I think that inside diameter is too small. That's why we had to go to the Trident website. See the earlier parts of this forum thread.

Ok. I could write a little or a lot. About how many word do you all like to see in these articles? ...just so I don't overdo it.

Hi everyone. I have a new problem. Apparently the new pipe I bought and installed is leaking a small amount of diesel exhaust at the threads.

This is plumbing pipe so the designers probably figured the plumber would seal the threads with teflon tape or some such.

To solve the problem, I bought some Permatex Ultra Copper High Temp RTV Silicone gasket sealant at Autozone.

My hesitation about applying it is that the package says "700 degrees F Intermittent", so I'm thinking it was designed for oil pans, valve covers and such, and not for the higher temps it would encounter in the exhaust riser.

I suppose that after a time, without any sealant at all the exhaust soot would probably clog the threads and self-seal the leak...but may be not.

Any other ideas for sealing these threads?

Hi Bud and Suzanne.

It's going to go through the 1-2 feet of pipe, but not the liquid-cooled mixing elbow.

I read up some more on the tech specs for the Permatex Ultra Copper High Temp RTV Silicone sealant, and it clearly states that it's designed for use on exhaust manifolds:

[url]http://www.permatex.com/products/automotive/automotive_gasketing/gasket_...

...so it looks like I'm ok on this one. I'll let you all know if this works out ok.

Ben

Good to know about the antifreeze jacket, Bud.

The silicone sealant appears to be working, but alas, I still have a small exhaust leak. Appears to be in the engine itself, but I can't pin its location down yet.

[QUOTE=chs1517;10274]Ben,

I have an 84 Catalina most likely a mirror of your boat as far as the engine goes. I had been planning on doing the same thing that you are about to do but have not gotten to that project yet. If you have the time would you please take some before, during and after photos of your project as well as note the particulars regarding what you ordered and who you ordered from? And... knowing that these projects normally go a little south, what problems you encountered and how you won the battle.[/QUOTE]

Hi, everyone. I've been speaking with Steve Frost on this and will not be able to publish the article in JibSheet at this time, but I would like to give some closure on it as the fix (the exhaust riser fix at least) appears to be working.

I will post this in several thread replies so that the text covers the pic(s) shown, as I don't know how to embed pics in text on this forum.

Pipe Union: A "union" is a special pipe with a metal seal and a threaded nut to hold the seal water-tight...and exhaust-tight in our case. I was able to get this at Southern Pipe Supply in Lilburn GA. (google it.) for about $10. Apparently ours is still a standard size coz they had an exact match right at the store. See pic.

After much discussion/research, I ended up taking the mixing elbow and the small nut you see on the right side of the pipe union (in my last post) to Fat Cat Fabrication in Buford GA (google it).

For $100 (ouch) he "brazed" the threaded whachamacallit into the mixing elbow after I had accidentally FUBARed the threads in the mixing elbow trying to remove the previous corroded whachamacallit from the mixing elbow. ("I may be ignorant but I ain't stupid!" - Loretta Lynn)

See pic.

After much discussion on this forum (thanks for the Trident tip again), I was able to order the correctly sized hump hose from River Supply, Inc. in Thunderbolt GA. (800-673-9391 or [url]www.riversupply.com[/url]). (Trident makes you order through one of their dealers who usually have to back-order it from Trident, so it took a couple of weeks to get this to me.) Part# is: 272V2000-SS. Description is: "TRIDENT HOSE BLUE SIL 2in"

Cost: $58 with shipping (ouch)...but after reading all the horror stories about broken aqualift muffler hose fittings due to vibration transferred from the engine through the exhaust riser to the muffler...including a brand new one (see "What's in YOUR muffler???" post by Stu Jackson)... this appears to be money well-spent.

Although the diameter was correct (see earlier posts in this thread), the hose was too long, so I simply measured and cut to approx size with a small hack saw. No biggie. Just make sure you don't cut it too short and have to order another one at $58 (ouch).

See pic.

As mentioned in an earlier post, after I put the whole thing together, it still leaked a small amount of exhaust fumes, so, as discussed in an earlier post on this thread, I bought some Permatex Ultra Copper High Temp RTV Silicone gasket sealant at Autozone, and smeared it everywhere I thought the thing could possibly leak...including the union itself and the whachamacallit (not shown in pic). After several "sea trials", this has apparently stopped the exhaust leak. See pic.

Oh, also, here's another pic of the silicone exhaust hump in place. Note the double clamps that came with the hump in the shipment. (Kind of nice of them to include those.) Note how it's not perfectly aligned, but (a) I suppose that's partly what the "hump" is for and (b) don't know what I could do to more closely align it in any case.

The owner of Fat Cat Fabrications suggested that I wrap the exhaust riser with what's called high-temp fiberglass "header tape". Apparently this is what one does on exhaust system "headers" on cars and motorcycles.

I got this at Advance Auto Parts (national chain, I believe.) With the locking ties, this set me back $63 (ouch).

The 50' x 2" roll was plenty to do the job.

Get the larger size stainless steel locking ties. I got the smaller 8" ones but had to double them up to go around the riser pipes. No biggie.

One tip from Fat Cat, who apparently does this kind of thing a lot: Soak the tape in water for a minute. This will shrink it down for a nice tight fit, once the water dries out. When you run the engine with the wet tape, obviously it's going to steam...but that's part of the shrinking process, I suppose.

Here are pics of the header tape and locking ties.

Here is a pic of the completed job.

In hindsight, after all the time and money I spent on this, I would not do it again. I'd simply order the new one from Catalina Direct, and be done with it all....for a few years...till that one corrodes out...unless, of course I just "loved working on my boat"...in which case I'd take it all apart and do it again next year...just for fun. :-)

[url]http://c2.com/cgi/wiki?LazinessImpatienceHubris[/url]

(Yes, I am a software engineer.)

[QUOTE=Channel Islander;11220]Do you code in Perl? That's when I learned the virtues of Laziness, Impatience and Hubris.

- nick[/QUOTE]

No, java these days. Not what I'd call the "laziest" of languages but it pays the bills. I pray for a lazy language to come along some day. :-)

[QUOTE=benethridge;11214]The owner of Fat Cat Fabrications suggested that I wrap the exhaust riser with what's called high-temp fiberglass "header tape". Apparently this is what one does on exhaust system "headers" on cars and motorcycles.

I got this at Advance Auto Parts (national chain, I believe.) With the locking ties, this set me back $63 (ouch).

The 50' x 2" roll was plenty to do the job.

Get the larger size stainless steel locking ties. I got the smaller 8" ones but had to double them up to go around the riser pipes. No biggie.

One tip from Fat Cat, who apparently does this kind of thing a lot: Soak the tape in water for a minute. This will shrink it down for a nice tight fit, once the water dries out. When you run the engine with the wet tape, obviously it's going to steam...but that's part of the shrinking process, I suppose.

Here are pics of the header tape and locking ties.[/QUOTE]

Heads up that this "hi-temp" fiberglass tape alone is apparently NOT adequate to handle the extreme temp coming out of the exhaust manifold. At full power, it smells like it's burning. Unless someone has a better idea, I'm going to take it off, add a layer of steel wire mesh followed by heavy-duty aluminum foil, followed by the fiberglass tape.

I'm guessing that the temp must be over 1500 degrees coming out of the exhaust.