Exhaust Hose-- Blue Silicone or ?

[ThirdHatt]

We finally got Sweet Melissa hauled today for a bottom job, etc. It's time to adress the old pieces of hard black exhaust hose that connect the various pieces of 8" fiberglass tubing. What is the best to use here? I am fortunate in that EVERY hose on both mains is blue silicone so no worries there, so I feel like I should get the silicone exhaust mainly because it will be SO much easier to install but also it's a good hose.

My weakest piece now is actually leaking a bit and it is directly behind/under the closet wall of the guest stateroom! You can look in OR you can put ONE arm in! I'm gonna haver FUN with this one!

Any marine exhaust hose do's or don't's here?

 

[captadamr]

We have used both types with our exhausts. The one thing I love about the Blue hose is you can get it to break free allot easier than that black hose. I would think that the black hose would be better if the strength of it is needed. Blue hose bends, kinks and gets sucked down too easily to be of any use for support. my $.02

 

[Jackman]

Ditto on the black stuff....I put the 5 or 6" double walled stainless wire reinforced stuff in from the exhaust outlet to the collector for the 454's. The stuff cannot be bent easily or at all and is tough to remove....which to me is the selling point. I don't it to ever come off! Especially while underway. I believe the clamps are for "good looks" and don't actually have holding power near that of the black hose. I have heard good about the silicone stuff though.

 

[Mike36c]

Silicone is far superior but get ready, they sell it by the inch!

 

[ThirdHatt]

I'll pay extra or silicone hose if it is right hose for the job. Apparently, black hose affords some support/structure in an exhaust system where the blue silicone would not be stiff enough. The problem is getting the stiff black hose fitted properly in a tight space without disassembling the rest of the exhaust!

Now I have to wonder about what Hatteras originally intended with the long stretches of 8" fiberglass tubes connected with short pieces of 8" hose. Hatteras did install some aluminum "support" brackets for the exhaust at the junctions of hose and tube. Unfortunately they seem like they may not be properly doing the job that they were intended to do.

Exhaust hose-sized leaks are potentially catastrophic so I really want to do this right before we go back in the water.

 

[captadamr]

Now I have to wonder about what Hatteras originally intended with the long stretches of 8" fiberglass tubes connected with short pieces of 8" hose.

Why did they do half the things they did 20 yrs ago that we frown on now. Guess there is some logic behind it........

 

[Genesis]

I replaced it and used blue. Would again.

Its a royal biatch of a job and you dont' want to do it twice. Trust me on that.

 

[ThirdHatt]

Genesis, That's all I need to hear. I'm sold on blue silicone for exhaust hose as well. Now, WHICH blue silicone hose brand?? Trident seems to be the thickest and most popular, but now I see that there are other manufacturers selling the stuff as well. Do you recall which brand you used?

One of my marine parts wholesalers sells a "Mylar Finish Shiny Blue Silicone Hose" that is 4-ply premium blue softwall hose. I can get it about 30% less than the Trident brand hose. The Trident hose is a bit thicker (possibly stronger but also more difficult to install). Are these all about equal or is one vastly superior to the other??

 

[Jackman]

I talked with hatteras when I redid my exhaust. They told me the fiberglass sections were put in for saving money. I like the black stuff but can't recommend the blue because I've never used it. Either way, both aren't cheap and it sounds like the blue stuff is even more expensive.

The black stuff seems to absorb vibrations better than the fiberglass sections that were there. I took them out and put in the black exhaust pipe from the stern to the engine and things vibrate less now, especially noticable at idle. I guess the rubber absorbs it better than the fiberglass. What's the blue stuff like as far as "vibratory properties"? (If that's a word)

 

[MikeP]

Well the thicker/heavier the material is the more sound/vibration it will absorb. That's why old cast iron house waste pipes are MUCH quieter than current PVC drain pipes. Though superior hose for many purposes the blue silicone hose can't absorb the sound/vibration as well as the black stuff simply because it has far less mass.

 

[jim rosenthal]

FWIW, we are using blue hose in the redo of Blue Note's exhaust system. This involves modifying a lot of it, so it isn't the same thing you are doing. I would use the blue hose and the best clamps I could get, sprayed after the fact with corrosion inhibitor. The harder something is to get at, the longer I want its replacement to last.

 

[ThirdHatt]

Jim, Do you happen to know the brand of blue hose that you are using by chance? My mechanic said to use the Trident as it is the thickest/stiffest of the blue silicone hoses. It sounds like the Trident may be the best of both worlds, stiff enough to absorb some vibration/noise yet flexible enough to make installation easier. I just know that I'll never want to deal with this issue again!

 

[jim rosenthal]

I think that is what we are using. I will ask Tom. The stuff does cost a lot, but it is supposed to last decades. Look at the RED stuff first, then the cost of the blue hose won't look as bad.

 

[MikeP]

Speaking of hose...I was in the marina store today when a lady walked in and asked for 4 ft of 4" exhaust hose - said her husband told her to get it. The owner cut the hose and then said "That'll be $48.50." The lady went nuts! She said, "WHAT? For Hose? That's ridiculous! I don't carry that much money around!" She walked out.

Good thing it wasn't silicone - they'd have had to send for the paramedics.

Guess she doesn't buy marine hose very often.

 

[thoward]

When I redid the Egg I installed wire reinforced black hose for most of the hoses. Never again! The wire reinforced is for long runs and is a total biatch to install.

 

[Bob Bradley]

Speaking of hose...I was in the marina store today when a lady walked in and asked for 4 ft of 4" exhaust hose - said her husband told her to get it. The owner cut the hose and then said "That'll be $48.50." The lady went nuts! She said, "WHAT? For Hose? That's ridiculous! I don't carry that much money around!" She walked out.

Good thing it wasn't silicone - they'd have had to send for the paramedics.

Guess she doesn't buy marine hose very often.

I never, ever, send my wife to pick up anything even remotely related to boating or fishing. OK, maybe cold cuts.

 

[Genesis]

I used the Trident and bought it from Hydraulic Supply. I've got a wholesale account with them.

It was NOT CHEAP.

 

[ThirdHatt]

After more research I found out that the "mylar finish shiny blue silicone hose" is made by Sheilds. It is good hose and my cost on a 8" 3' piece is $230. That hose is 4-ply. They can special order the Trident, but my cost is $305. The Trident hose is thicker/stronger because it is 6-ply. Ironically, I found a place (www.mesamarine.com) that sells the size I need in Trident for $274! I've never been so excited to pay so much for so little!

 

[Liquid Asset]

Yall need to call Metcalf Marine Exhaust in Ft. Lauderdale. They have good prices on the Blue stuff. Ask for Mike Mullet and let him know I refered you.

 

[ThirdHatt]

Pat, I called Metcalf Marine today and Mike Mullet no longer works there! At any rate, they only want $150 for the same 8"x3' piece of silicone hose that I just paid $274 for, but it is not made by Trident it is their own brand. Still great stuff, pure silicone 350 degree hose. Their website says the hose is 3-ply and I know Trident is 6-ply so for this instance (right off the exhaust collectors) I'll stick with the 6-ply. I will most certainly use them in the future for coolant or water lines though! Thanks!