Thread dope for exhaust fittings? - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance > Engines > Diesel
 Not a Member? 

Diesel This is a new forum dedicated to diesel engines and their applicable accessories.


Like Tree2Likes
Reply
 
LinkBack Thread Tools
  #1  
Old 08-29-2013
Senior Member
 
Join Date: Sep 2012
Location: Bremerton, Washington
Posts: 184
Thanks: 4
Thanked 0 Times in 0 Posts
Rep Power: 2
Rusty123 is on a distinguished road
Thread dope for exhaust fittings?

Any effective products to put on the threads of mixing elbows and associated bits to make them easier to disassemble for replacement next time? It took me 3 days of Kroil, a torch, and a 4 foot breaker bar to get them apart this time (although the threads looked remarkably good once I got them apart).
__________________
1981 Spirit 28 "Bonnie Lass"
Bremerton, Washington
Reply With Quote Share with Facebook
  #2  
Old 08-29-2013
Senior Member
 
Join Date: Feb 2010
Location: Narragansett Bay
Posts: 8,691
Thanks: 10
Thanked 113 Times in 107 Posts
Rep Power: 6
Minnewaska will become famous soon enough Minnewaska will become famous soon enough
Re: Thread dope for exhaust fittings?

You can get high temperature anti-seize, however, I might then worry about the bolts backing out and leaking exhaust. Best might be to take them apart more often to inspect and clean.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Jeanneau 54DS

In the harsh marine environment, something is always in need of repair. Margaritas fix everything.
Reply With Quote Share with Facebook
  #3  
Old 08-29-2013
Maine Sail's Avatar
Senior Member
 
Join Date: Jan 2003
Location: Maine Coast
Posts: 5,269
Thanks: 9
Thanked 113 Times in 83 Posts
Rep Power: 15
Maine Sail is just really nice Maine Sail is just really nice Maine Sail is just really nice Maine Sail is just really nice
Re: Thread dope for exhaust fittings?

Been using Hercules Rea-Tuff pipe dope for years and years on exhaust fittings.. You can get it at any Home Depot..
__________________
______
-Maine Sail / CS-36T


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




© Images In Posts Property of Compass Marine Inc.


Reply With Quote Share with Facebook
  #4  
Old 08-29-2013
trantor12020's Avatar
Senior Member
 
Join Date: Mar 2006
Location: Singapore
Posts: 668
Thanks: 1
Thanked 10 Times in 10 Posts
Rep Power: 9
trantor12020 is on a distinguished road
Re: Thread dope for exhaust fittings?

I've used anti seize which seize. Last year i had to use flame to help unscrew the elbow. I use Teflon tape after that. Last week i unscrewed it with just pipe wrench. No struggle. So from now, I'll use Teflon tape. I've no leak with Teflon tape.
__________________
Ken
2002 Hunter 326, SV Millennium 2
1999 Macgregor 26X, SV Millennium
Reply With Quote Share with Facebook
  #5  
Old 08-29-2013
Senior Member
 
Join Date: Feb 2010
Location: Narragansett Bay
Posts: 8,691
Thanks: 10
Thanked 113 Times in 107 Posts
Rep Power: 6
Minnewaska will become famous soon enough Minnewaska will become famous soon enough
Re: Thread dope for exhaust fittings?

I thought teflon would melt/burn well below exhaust gas temps. Perhaps that heat dissipates a bit by the time it soaks to the bolts. Maybe more on some than other setups. I also thought burning teflon was poisonous.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Jeanneau 54DS

In the harsh marine environment, something is always in need of repair. Margaritas fix everything.
Reply With Quote Share with Facebook
  #6  
Old 08-29-2013
Omatako's Avatar
Senior Member
 
Join Date: Sep 2003
Location: Auckland New Zealand
Posts: 2,376
Thanks: 0
Thanked 25 Times in 22 Posts
Rep Power: 11
Omatako will become famous soon enough
Re: Thread dope for exhaust fittings?

Quote:
Originally Posted by Minnewaska View Post
I thought teflon would melt/burn well below exhaust gas temps. Perhaps that heat dissipates a bit by the time it soaks to the bolts. Maybe more on some than other setups. I also thought burning teflon was poisonous.
Don't they use Teflon to coat frying pans?
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

__________________

"Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying."

Arthur C. Clarke
Reply With Quote Share with Facebook
  #7  
Old 08-29-2013
hellosailor's Avatar
Plausible Deniability
 
Join Date: Apr 2006
Posts: 10,423
Thanks: 1
Thanked 75 Times in 73 Posts
Rep Power: 10
hellosailor has a spectacular aura about hellosailor has a spectacular aura about
Re: Thread dope for exhaust fittings?

"Don't they use Teflon to coat frying pans? "
Yes, and the fine print usually says you will generate phosgene gas and kill someone if you let the Teflon get over 500F. Or gentler words to similar effect.
Ignoring the finer details, Teflon releases nasty gasses when it gets too hot. Which is one reason there are "ceramic" coatings on the better skillets these days, and some of those make Teflon look like junk because they are so much better at not sticking.
Going back to exhaust fittings...I don't think most of the joints would exceed the Teflon critical temperature but I'd verify that before using Teflon there.
Reply With Quote Share with Facebook
  #8  
Old 08-29-2013
Senior Member
 
Join Date: Feb 2010
Location: Narragansett Bay
Posts: 8,691
Thanks: 10
Thanked 113 Times in 107 Posts
Rep Power: 6
Minnewaska will become famous soon enough Minnewaska will become famous soon enough
Re: Thread dope for exhaust fittings?

Thought Teflon melts around 600 degs, which would make sense, if manufacturer suggestion is 500. Exhaust gas temps easily exceed 1,000 degs, although, that may not be the temp that reaches the bolts.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Jeanneau 54DS

In the harsh marine environment, something is always in need of repair. Margaritas fix everything.
Reply With Quote Share with Facebook
  #9  
Old 08-30-2013
Member
 
Join Date: Mar 2007
Posts: 55
Thanks: 11
Thanked 3 Times in 3 Posts
Rep Power: 8
kentobin is on a distinguished road
Re: Thread dope for exhaust fittings?

More information to amuse and confuse:

Exhaust Pipe Thread Sealer - Cruisers & Sailing Forums
Reply With Quote Share with Facebook
  #10  
Old 08-30-2013
Omatako's Avatar
Senior Member
 
Join Date: Sep 2003
Location: Auckland New Zealand
Posts: 2,376
Thanks: 0
Thanked 25 Times in 22 Posts
Rep Power: 11
Omatako will become famous soon enough
Re: Thread dope for exhaust fittings?

Quote:
Originally Posted by Minnewaska View Post
Thought Teflon melts around 600 degs, which would make sense, if manufacturer suggestion is 500. Exhaust gas temps easily exceed 1,000 degs, although, that may not be the temp that reaches the bolts.
At 1000° there would be melt-downs of all kinds of components. The temperature of the gas that leaves the cylinder head cools really fast when it gets to the cooling jacket around the manifold.

The water that pours into the manifold jacket will never reach boiling point and by the time it reaches the elbow it is probably not hot enough to make tea.

My exhaust has a glass fibre elbow - I suspect that it would burn through quite a lot earlier than 500° - in fact I would be astonished if it reached even 100°C

The mixing elbow has an unfortunate name - it doesn't mix super-hot exhaust gas with cold water. Actually the exhaust gases generally reach the "mixing elbow" heavily laden with water and mostly the elbow is where the excess water that doesn't go to the exhaust manifold jacket is included in the out-flowing mixture. There is no way that it gets hot enough to melt Teflon.

At least that is my experience - YMMV
SVAuspicious and Minnewaska like this.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

__________________

"Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying."

Arthur C. Clarke
Reply With Quote Share with Facebook
The Following User Says Thank You to Omatako For This Useful Post:
Minnewaska (08-30-2013)
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hi Mod fittings casey1999 Gear & Maintenance 18 02-03-2014 12:28 PM
Swaged fittings vs. mechanical fittings yachtthor Pacific Seacraft 24 04-21-2012 04:48 PM
Dope on threads? L124C Diesel 7 02-23-2010 08:06 AM
best pipe dope? scosch Gear & Maintenance 10 02-15-2009 08:46 PM


All times are GMT -4. The time now is 06:50 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.