HELP- Swapping Flappers to SS Silent Tip Exhaust

[Dacon62]

Have a Prostar and want to swap out the flappers to STE. Like the boat a bit quieter. Dealer says will take 6-8 hours ($129/hour shop rate) to do the job and he’s apprehensive to do it.

 

Complications are,

1) Hose clamp access. 2 of the 4 gears are on the side of the exhaust are not accessible because the fuel tank.

2) 3M 5200 adhesive is a bear. Could tear out some gel.

3) Hard to cut hose clamps off with a cutting wheel because cutting blind also danger of explosion as fuel tank is right there.

 

Anyone out there done this and could offer some advise. Thanks.

[oldjeep]

Cut the adhesive with fishing line. Cut the clamps with a wire cutter. Use a heat gun to warm up the hoses before trying to pull them off.

 

Cool factor? You spend a lot of time looking at the back of your boat on the trailer?

 

In these days of no carpet, I highly doubt that the flange change is going to make much difference in the boat noise.

[Orlando76]

All good points @oldjeep pointed out (but I think more sound is cooler, guess I’m still a kid). Carpet is a miracle work in a boat or car. I’d like some more info on cutting 5200 with fishing line though.... I have something coming up.

[Dacon62]

Have heard of a 5200 solvent called Debond and piano wire but not fishing line.

The biggest challenge I think is getting the hose clamps off they are very tight and countersunk into the exhaust hose rubber, not to mention hard to access.

One guy on TT said he had loosened the clamps that attached the exhaust hose to the mufflers and after softening and prying the exhaust flange off he was able to pull the exhaust hose out through the through hull bored hole and get to the clamps that way.

Question is I don’t know if the bored hole is big enough on a Prostar to get the exhaust hose with the clamps on out the hole? He did not mention which boat model he had.

[DW]

I swapped out the plastic tail pipes to stainless tips on my Malibu, was not too bad a job. It has inline mufflers so getting those out created room to pull exhaust hose forward. I loosened the clamps on the tips first, spun the muffler to break the rubber hose free as it provided a surface to grab. hose clamps were not super friendly to pop off, IIRC used a stubby screwdriver for them. Heat, piano wire and solvent were used on the tips but they were not really that bad and since the tips were 4" the surface was not super important as the original tips were much smaller.

[liquid d]

Isn't that covered with a ski platform? Man, you Canadians just look for shit to do during the winter, don't you!

[bigskieridaho]

Leave the flappers. Those MC’s sound epic

[Dano]

A heat gun can be used to heat the thru hull which will essentially melt the 5200 so it will release and the thru hull can be removed without damaging the gel/fiberglass.

 

[chrislandy]

When I changed the exhaust hose on my 205 I just took the rear floor off lay down on the floor, reached under the fuel tank and used a 5/16 socket on a 1/4 ratchet to get to the hose clamps. Once the hose was off I could have accessed the rear of the flappers if I'd wanted to replaced them (I didn't though as I like the sound and the backwash protection they provide!)

[Jody_Seal]

6-8 hours seems a bit high! I would charge 2-3 hours with no hesitation. 5200 is not normally used for exhaust tips. If so a heat gun and a bit of fanageling they should come right out.

[Jetsetr]

Nothing sounds as good as a 351 in an early ski boat...EXCEPT a 500 inch AJPE on 95% ch3no2...

[MichaelWiebe]

How did this job turn out?

And was it noticeably quieter?

Thanks in advance.

(We are early morning skiers, and are considering doing the same on our ProStars.)

[BraceMaker]

FAE?

[UWSkier]

Do you care how it looks all that much? I've had these on my boat for a while and nobody has ever noticed their presence, but the sound decrease outside of the boat is considerable. See video for example.

 

https://www.themalibucrew.com/index.php?/forums/topic/72457-ghetto-exhaust-downturns-with-video/

[MDB1056]

I’m shocked that anyone would want to invest this much time effort and money into making it quieter. If it was too loud why would you buy the boat in the first place? Those MC’s sound great, and aren’t in any stretch loud...IMO.. You guys must be really anxious for the electric boats to arrive.

[BraceMaker]

@MDB1056 the sport has zero benefit from boat noise. Negative impact on safety, driver/crew hearing health, noise complaints cause hour bans on lakes. The quieter the better. Maybe other than jump.

[m_pags]

@MDB1056 I have permitted course on public water that can be revoked by the lake association at any time. So I need to be respectful of everyone. This includes boat noise and even the language of myself and ski buddies. I installed a FAE a couple of years and it's been worth every penny I spent on it. Not one complaint about noise since it was installed and no I'm not intrested in an electric boat.