putting exhaust back together.. quick question on wether to apply anything to connect

[vaser21]

hey guys i am putting my exhaust back together on my 95 xp 720, i got all new gaskets and washers, but there is this one big circle connection, do i apply any sealeant or anything on it, or do i just connect it?? i will attach a picture,

thank you guys in advance

 

[Dr Honda]

Any sealant you put in there will cook out.

Did you get a new seal for that? If you did... just put it in dry, and put the clamp on. If you didn't... it's going to leak.

 

[vaser21]

Any sealant you put in there will cook out.

Did you get a new seal for that? If you did... just put it in dry, and put the clamp on. If you didn't... it's going to leak.

Seal?? What seal? I order the gasket kit from sbt and it didn't come with one?? Ugh.. I really want to be on the water tommorow, what can I do?? Cut my own gasket?.. Any idea what kind of material that seal is?

 

[Thumper3322]

I cleaned up both sides and used ultra Cooper around the bottom side, then carefully put it back together. I tightened everything in rotation once it lined up. Then has to dry for 24 hours.

Did 2 skies like this, so far so good.

 

[1MACGYVER]

When in doubt apply more lubricant.. or in this case sealant.
It will leak without anything, +1 for copper high temp gasket silicon

 

[sledder12]

I used copper high temp gasket sealant as well, even put a thin layer on all the gaskets, no issues whatsoever

 

[Dr Honda]

Seal?? What seal?

You can see it in the picture. it's a copper crush ring.

Ultra copper RTV is only, realistically, good for about 500 degrees F. It can take a 700 deg for a short period. Your exhaust temps can reach 1200 degrees F if you are holding the throttle open.

You guys can do what you want. You won't hurt anything by putting RTV on it... but you will be taking it part again later. OR... worse yet... you will make a post 3 months from now saying... "why is my ski dying for no reason after 3 minutes of riding?" OR... "Why can I only get 4500 RPM out of my engine?" (it will be from the exhaust leak smothering the engine)


As always... I'm not trying to be harsh... I'm just trying to give you guys the info needed to make good choices, and to keep your skis running trouble free.

 

[470]

You could go with or without sealant. While it is true the exhaust can reach 1200º that number is taken 100mm off the piston skirt and drops fast when hitting the water cooled manifold and pipe. I've run 2+ miles wide open with no seat on and can hold my hand on the motor or pipe comfortably.

 

[Dennis]

I disagree with doc. Using high temp silicon sealer is the correct thing to do. Even states it in the service manual. That pipe doesn't get that hot. If it ever does you're already have a engine melt down. A new copper crush ring would be nice but not absolutely necessary. I've reused those rings many of times with no issues. :cheers:

 

[vaser21]

alright guys, i saw the copper ring, so i slabbed a bunch of high temp rtv on it, just so i could get out on the water todayy!!! willl be purchasing a new one and when it comes in, i will install and apply whatever the service manual says..

thank you all for your thoughts tips and advice it is greatly appreciate it,,,,,, now if you excuse me i am headed to the lake!!!

 

[Comp]

If it was a car or motorcycle exhaust I would agree the silicone would never hold up, but the entire head pipe is water jacketed and doesnt get all that hot. If it was getting over 500 degrees everything in the engine compartment would be melting. Mine had red high temp on it when I took it apart, used it when I put it back together and have had no trouble with it.

As for the copper ring, you probably dont need to buy a new one. You can just anneal the one you have and put it back in. We do it all the time with copper head gaskets on race cars. Heat the gasket with a torch or in an oven. The copper will go back to a soft condition and make a better seal.

 

[Dr Honda]

You guys can disagree all you want. (it's a free country) BUT... Reassembling the exhaust using old gaskets is wrong. PERIOD.

I will agree, the outer jacket of a PWC exhaust is relatively cool since water is flowing... but the exhaust gasses (in side) are still hot enough to cook the RTV.

I try to give you guys the proper way of doing things. Also... if I know something that will work, or be acceptable... I always tell you guys that too. In this case... you need an $8 gasket to do it right, and have the peace of mind that you won't have an engine shutting down in the middle of the lake.


So... that's the last I will say on this.


Vaser21: Thanks for listening. The RTV is fine to get you though a weekend.

 

[Thumper3322]

I was only restating what people suggested in my post, and what I did. I never did end up taking the copper gasket out, as to me it still looked like one piece. So I cleaned everything up and used ultra copper rtv as chester suggested. The manual does indicate a sealant loctite 17914. Figured the ultra would just hold up longer. No leak so far, but it if does will know what to fix :thumbsup:

http://www.seadooforum.com/showthread.php?49518-787-exhaust-installation-help