Outdrive exhaust "sock"?

paulbrown22 · 26 July 2014, 17:18

The exhaust sock (for lack of a better description) on my outdrive Ribtec has a slight tear in it that will only get larger, so would like to replace it.

Any ideas what it's made of, or who makes them?! Seems to be a much thicker material than hypalon and presumably designed to cope with heat, formed into a 10cm diameter tube that's clamped onto a transom fitting.

Peter_C · 26 July 2014, 17:29

Do you mean the blue thingy? That would be an elephant trunk for draining water out off the deck of the boat. It should be tied up when not needed.

paulbrown22 · 26 July 2014, 17:34

Yep, that (large) blue thingy - but it's the exhaust sock on this boat!

Elephant trunks are smaller diameter port/starboard.

tonymac · 26 July 2014, 17:36

Quote:

Originally Posted by paulbrown22

The exhaust sock (for lack of a better description) on my outdrive Ribtec has a slight tear in it that will only get larger, so would like to replace it.

Any ideas what it's made of, or who makes them?! Seems to be a much thicker material than hypalon and presumably designed to cope with heat, formed into a 10cm diameter tube that's clamped onto a transom fitting.

You sure ????

Peter_C · 26 July 2014, 17:47

Isn't that a Bravo 3 outdrive? In which case it should be thru hub exhaust. Does it have a valve for changing where the exhaust goes? Is the blue tube run after a muffler? Do you have an inside photo?

I have seen exhaust pipes come out the back on high performance boats but typically it is two mufflers and two outlet tips with nothing on them except the flappers. Some can be switched from cool mode to uncool mode. Loud to quiet mode. (I prefer quiet myself.)

If it is an exhaust, why not just put an exhaust flapper on?

biffer · 26 July 2014, 18:04

They use to use flat water pump hose, four inch I think, they never run them through the hub in the early days, from memory it was something to do with turbo back pressure

paulbrown22 · 26 July 2014, 19:10

Many thanks both.

Peter - yes, it's a Bravo 3, but this particular example has never had a through hub exhaust from what I can see, it just goes directly from the exhaust mixing elbow out the transom, with this flexible pipe connecting to the transom flange instead of a flap gate. I guess I could replace it with a flap gate, I was just looking at replacing like with like as I assume that's how it's been for the last 10 years (I've only owned for 2 years).

Biff - perfect, have found some 4" water pump pipe and that looks identical. Given the minimal cost I shall order a metre of that and give it a go (appropriately cut down obviously)!

Peter_C · 26 July 2014, 19:31

Careful on the water pipe as some of it is really heavy duty and won't collapse as your current one will. I have some in my garage...

paulbrown22 · 26 July 2014, 20:32

Thanks Peter - I've ordered some light/medium duty stuff that appears to be the same as what's currently on there, but I will certainly check it before fitting.

Pikey Dave · 27 July 2014, 21:40

Quote:

Originally Posted by paulbrown22

The exhaust sock (for lack of a better description) on my outdrive Ribtec has a slight tear in it that will only get larger, so would like to replace it.

Any ideas what it's made of, or who makes them?! Seems to be a much thicker material than hypalon and presumably designed to cope with heat, formed into a 10cm diameter tube that's clamped onto a transom fitting.

assuming it's the blue thing dangling in the pic, it looks like layflat hose, I thought it was the elephant trunk bailer.

biffer · 27 July 2014, 22:04

How olds your boat, I might have rigged it when I was at Ribtec, I did a few of them while I was there, you could convert it to through the drive, I've done one with a bravo 2 drive and it's been ok with no problems

Daniel · 28 July 2014, 07:20

Like someone's earlier post, I thought there was a reason the 6LP wasn't through the drive.

I remember the through-drive water inlet is insufficient for the 6LP and it needs an additional skin fitting and strainer.

Only reason I can think of regards exhaust is turbo lag, but magellan's 4" lay flat was below the waterline. This I think was to improve exhaust silencing at rest, but surely would have introduced the same back pressure as through drive?

biffer · 28 July 2014, 08:03

On later installations i used to run a second water outlet off the water mixing elbow to cool the drive, we are getting away from the thread though, it's lay flat water pump hose, we used that because water doesn't go back up it very easy at rest.
I've got 2 of these installations to do in my sunseeker and I'm thinking of doing something special, don't know what yet though

paulbrown22 · 28 July 2014, 17:58

Quote:

Originally Posted by biffer

How olds your boat, I might have rigged it when I was at Ribtec, I did a few of them while I was there, you could convert it to through the drive, I've done one with a bravo 2 drive and it's been ok with no problems

It was sold to me as a 2004. When I checked the engine number with Barrus the engine came back as a 2003, so presumably somewhere 2003/2004ish.

I'm happy with the exhaust as is, no need to go to through hub - it's not massively noisy, and at least this keeps it simpler. Just needs some new hose!

Will be talking to you later this year/early next year about a possible deck replacement and changing the deck configuration a bit - just haven't yet worked out exactly what I want!

paulbrown22 · 28 July 2014, 18:00

Quote:

Originally Posted by Daniel

Like someone's earlier post, I thought there was a reason the 6LP wasn't through the drive.

I remember the through-drive water inlet is insufficient for the 6LP and it needs an additional skin fitting and strainer.

Only reason I can think of regards exhaust is turbo lag, but magellan's 4" lay flat was below the waterline. This I think was to improve exhaust silencing at rest, but surely would have introduced the same back pressure as through drive?

Is it underwater at speed though? My hose does just touch into the water at rest and very slow speed, but any faster than that and it's on the surface.

Assume my setup is much the same as Magellan's - it's got both through drive and a separate skin fitting for water intake - supposedly the through drive isn't enough, but having it in addition to a separate pickup does vaguely help with cooling the drive a bit as well.

paulbrown22 · 28 July 2014, 18:02

Quote:

Originally Posted by biffer

On later installations i used to run a second water outlet off the water mixing elbow to cool the drive, we are getting away from the thread though, it's lay flat water pump hose, we used that because water doesn't go back up it very easy at rest.
I've got 2 of these installations to do in my sunseeker and I'm thinking of doing something special, don't know what yet though

I've seen a couple of nice installations on RIB's (think one was a Scorpion) that had a stainless spigot above the drive that was presumably a shower running off the mixing elbow or similar.

I fitted a standard IMCO shower to mine when I bought it as an easy fit to try and ensure it is suitably cooled, but that certainly looked like a much neater approach.

biffer · 28 July 2014, 18:05

The tale is that the 315s eat bravo 3 drives so the showers keep them cool

paulbrown22 · 28 July 2014, 20:18

Yep - I was very surprised mine didn't already have a shower, given everything you read about the 6LP/Bravo 3 combo! Think I bought my IMCO shower the day after buying the RIB - for such a simple fitment, it seems stupid not to have one to try and enhance the cooling and prolong drive longevity.