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C_Feath
06-24-2009, 02:34 PM
Hello All, I just joined the site...glad I found it. Very cool. My boat is in storage so I can't measure them myself without a good drive to get to the boat and I checked the online manuals to check the size on the exhaust flaps for my '84 stars and stripes but couldn't find anything. Can anybody tell me wether they are 3" or 4"? Thanks!

TMCNo1
06-24-2009, 05:13 PM
3" if I'm not mistaken. Here they are, http://www.skidim.com/prodinfo.asp?number=JMS32-05018 and you can also, call them if need be.

woodskier
06-24-2009, 05:16 PM
Sorry TMC01, I think they are 4". I can check when I get home on my 84 S&S. But since you are the MAN, I must be mistaken. Will check

454Prostar190
06-25-2009, 11:47 AM
Mine, on my '82 are 3". Although, if you're measuring the outside diameter..... it may be closer to 4". When you are giving a dimension for a piece of pipe.... the inside diameter, of said pipe, is the number.

TMCNo1
06-25-2009, 02:03 PM
Sorry TMC01, I think they are 4". I can check when I get home on my 84 S&S. But since you are the MAN, I must be mistaken. Will check

Whatever you say, I'll agree. I try to learn something new everyday.http://smileys.smileycentral.com/cat/10/10_4_6.gif (http://www.smileycentral.com/?partner=ZSzeb001_ZSfox000)

TMCNo1
06-25-2009, 02:17 PM
Mine, on my '82 are 3". Although, if you're measuring the outside diameter..... it may be closer to 4". When you are giving a dimension for a piece of pipe.... the inside diameter, of said pipe, is the number.

That's what I've always been taught,
Plumbing dimensions aren't always what they appear to be. A plastic pipe with a 3 3/8-inch outside diameter, for instance, is actually called a 3-inch pipe because it has a 3-inch inside diameter and pipes are usually sized according to their inside diameter (ID). This dimension is also referred to as the nominal size, the size you ask for.

TRBenj
06-25-2009, 03:12 PM
That's what I've always been taught,
Plumbing dimensions aren't always what they appear to be. A plastic pipe with a 3 3/8-inch outside diameter, for instance, is actually called a 3-inch pipe because it has a 3-inch inside diameter and pipes are usually sized according to their inside diameter (ID). This dimension is also referred to as the nominal size, the size you ask for.
That is very true- but the metal pieces in the exhaust (including the tips) are not considered "pipes" but rather "tubes". Tubing is referenced by its OD, pipe and hose by ID. That is why you can buy 3" SS or AL exhaust tubing and put it in place of the mufflers regardless of the wall thickness. The OD on the tubing perfectly matches the ID on the corrugated hose.

That being said, I would be very surprised if the OP's boat had anything other than a 3" exhaust system.

sam196370
08-21-2011, 01:44 PM
I just bought a '79 S&S and had some water leaking in from the rear on my first few runs. Boat had not been in water for 2 years, as I was approaching the launch it started taking in serious water - haven't tried to figure out where it's coming from but I assume it's the exhaust outlets since I'd think it's tough for a huge amount to come in through prop/rudder seals; any troubleshooting methods? Is it hard to re-seal the exhaust outlets?