Blown muffler rebuild - Easy

I wanted to share with members my recent experience regarding the Hull Hugger muffler on my 97 SN.

Over the weekend I noticed a crack (and water leak) in the muffler. Upon pulling it Sunday night I found out that the bypass tube inside came loose. After almost having a heart attack over the $550 cost for a new one, I decided to rebuild it myself.

I'll post the details in a couple weeks after I confirm that it worked, but basically I cut an access hole on the larger side, re-epoxied the tube in place, then rebonded the piece I cut out. It looks good this morning and I am going to give it a try tonight. Total cost about $35 and 2 hours. If it works that makes for quite a bit of beer money...

I'd be really interested in seeing some pics.

hey i know you posted this ages ago but i have a question, i also have a 97 sport, i have to pull my hull hugger as i have a leak there somewhere also. I noticed last night when looking around it that it has worn the fibreglass underneath it(the Hull) especially under the corners of the hugger. Did you have this issue? Not sure if i have to just get some rubber mat for it to stop the rubbing between it and the hull, or do i also have to repair the hull as well? Any thoughts would be greatly appreciated.

i Had it on boat point but took it off, i couldn`t find it when i looked for it. Hope they took it down as i have a shed for the boat now and am starting to do a lot of work on it. I may need to ask you some more questions in the future, sounds like you have done heaps to you ski. I plan on doing interior soon.

Here is a picture.

I have removed the hull hugger today and havenoticed how much it has worn. Also under thehugger was very worn so i have repaired with poly resin and fibre sheet. I will post some photos, of the repair job on the hullhugger and the need of repair of the hull, does anyone have any suggestions about repairing the hull? e.g. what i should use etc.. any help would be greatly appreciated, i wanted to have her back on the water next weekend.
Any guidance from the experienced guys here is always great thanks again.

Steve

Steve,
From the pictures, to me it looks like only the decorative gel coating is worn off the hull. Personally, I wouldn't worry too much about it.

Steve,
You can put some new gel down if you want but as mentioned, it's decorative and I feel the muffler will cover up the worn spots.

I'd just sand the gloss off the muffler repair and spray it with a aerosol can of semi gloss. Nothing special.

Jim - There is a ton of pressure inside the muffler when you bury the throttle from idle. This pressure is most likely what caused the crack. I would remove it from the boat and shake it to make sure that the bypass tube inside has not came loose (common problem).

ALSO, YOU CAN FIX THIS YOURSELF, IT IS EASY.

Go to an auto parts store and pick up a fiberglass repair kit. This will contain resin, hardener, and woven fiberglass. I would avoid the random weave stuff as when it gets covered in resin the fibers start to come off. Also pick up a pair of plastic gloves, course sandpaper, and acetone. Here is the process:

1. Sand ALL the black off the area, the more the better. I would do an area at least 4" x 6", but 8 x 11 would be even better. If you have a vibratory sander or something similar that works great. Be agressive and make sure and sand into the glass a bit (you won't damage it).
2. Clean the area with Acetone and let it dry for at least 30-60 minutes.
3. Cut two pieces of glass slightly smaller than the cleaned area. This is important, DO NOT make it the same size as the cleaned area because you don't want any resin or fabric to extend onto the painted area because this will cause premature failure of the repair.
4. Mix the resin and hardener. Remember, you need to be completely done in about 15 minutes from this step.
5. Apply a coat of light resin to the surface.
6. Apply your first layer of fabric and using a tapping motion with the saturated paint brush work the bubbles out of the fabric.
7. Apply another coat of resin over the top so the surface is fully coated.
8. Repeat with the second layer of fabric.
9. Let cure for 24 hours before use.

I would plan a total time of about four hours, easily done on a weekend afternoon.

Good luck! If you have any questions just ask.
All
4.

If you can reinforce it, do it now!

On my muffler the baffle is secured using two 'L' brackets between the tube and the upper and lower inside housing that is fiberglassed in place.

If you have a hole fix it now. All you need to do is sand it down, clean it with some carb cleaner, then re-glass it. Let me know if you have any specific questions.

Can you reach in and pull out the loose baffle? Probably better not too have it, then to have it get lodged somewhere undesirable.

Just get rid of the muffler altogether.

winniskier wrote: I understand the sentiment, but I need to hear your reasons before I go spending $600 on a new one.

He's most likely suggesting a Y-pipe conversion as discussed here:
http://www.nautiqueowners.com/forum/forum_posts.asp?TID=14912&PID=172459&title=replacing-muffler-with-y-pipe-on-97-nautique

It would cost a couple bucks to get the Y and you might need some additional exhaust hose, but still a lot cheaper than a new muffler.

I was going to suggest this earlier, but I figured where you were going to so much trouble to fix the baffles, you must like the boat quiet. I'd be curious to see what it sounds like without the muffler. I'm kind of considering tossing my invertaflow in favor of the Y, but I do ski early in the morning on a small lake, so I figure I'll keep the muffler until it gives me problems.

Here it is repaired.