Re: [Amel Yacht Owners] Illustration of the Onan Exhaust Elbow Replacement

Bill Kinney <greatketch@...>


Now that’s a fun fact!  But I guess magnesium hydroxide could be as good a thread lubricant as anything else.  Just be sure to use the “unflavored” variety.  :-)

I am not aware of  any single thread lubricant or anti-seaze that works in every situation on a boat.  I generally keep a few kinds in my tool box. 

A teflon based product like Tef-Gel for stainless screws into aluminum, and stainless-on-stainless threads under high load.  
Lanocote, for lots of general purpose applications.
Marine-grade Never-Seeze for most everything on the engine and any other high temperature applications.  Also good for preventing galling with stainless-on-stainless pipe threads.
Blue Loctite for things that need help staying together.

They all do something a bit different from each other, and which one that gets used depends on what I want to happen.  Do I want to lubricate the threads to make a tighter joint?  Is it a part that gets wet so galvanic isolation important? Is the temperature range unusual?  Is it an electrical connection so conductivity needs to be considered?  It is really rare that threads get tightened on my boat without something on them.

Just as an aside, one of the things that I find makes my future life happier is anytime I buy a new piece of equipment, especially if it has stainless screws, is I pull all the screws out and lubricate them.  A future disassembly then has much less aggravation.

Of course, these are the brands that I use because they are easily available to me, and have been good to me in the past.  I am sure there are lots of others that are at least as good.

On Sep 4, 2016, at 11:13, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Bill and Alexandre,

   I thought that I would mention that the Kennedy Space Center uses (don’t laugh) Phllips unflavoured Milk of Magnesia on the threads of fasteners that will be exposed to high temperatures to allow for easy removal.  I have used this solution on exhaust systems of cars and boats for a long time and it really does work.  I am sure that there are other products and you may have as good of a solution but thought I would toss this in as an option.  Some of the anti seize compounds contain metals that are quite high on the galvanic scale which concerns me some...



SV Sueno,  Maramu #220

On Sep 4, 2016, at 11:22 AM, Bill greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:


I would change the Lanocote.  At best, it will melt and run out of the joint leaving it unprotected.  At worst it would decompose in place and potentially glue the fasteners in place.  Lanocote is made from the grease from sheep's wool and will not survive in the 600 C temperatures of a diesel exhaust manifold.


On Sep 4, 2016, at 07:32, Alexandre Uster von Baar uster@... [amelyachtowners] <amelyachtowners@...> wrote:


Good morning Mark & Bill, 

Thank you so much for your input.  
I just added your note on the illustration.  

Bill, do you think Lanocote will made more bad than good (and should change it now)?  

Compare to some story I remember reading with similar hours, I thought the carbon built up was pretty reasonable on mine. 
Now that I have the Blue Sea AC Multimeter, I will be able to run appropriately the genset and minimize carbon build up.  

Thanks to both of you, hope more people comment.  
Have a great weekend!

Sincerely, Alexandre
Club Nautico de San Juan, Puerto Rico

On Sat, 9/3/16, Bill greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

Subject: Re: [Amel Yacht Owners] Illustration of the Onan Exhaust Elbow Replacement
To: amelyachtowners@...
Date: Saturday, September 3, 2016, 6:53 PM


Great job, and helpful
I only have
two comments.
 It is
not a good idea to reuse lock washers, especially in a high
temperature application like this.  They anneal and lose
their "spring" and do not do a good job the second
time around. 
You are
also right to use an anti seize on the bolts, unfortunately
Lanocote is not right for this application.  It will not
stand up to the temperatures of a diesel exhaust manifold.
 For engine work I use a product called
"Never-Seez" that is rated for higher
temperatures.  There are lots of others that work, most of
them are a suspension of powdered copper.
With a new gasket, and clean mating
surfaces I wouldn't use RTV on this unless I had
previous problems with leaks.  
Bill KinneyHarmonie,
SM160Narragansett Bay, RI, USA
On Sep 3,
2016, at 17:07, Alexandre Uster von Baar uster@...
[amelyachtowners] <amelyachtowners@...>


Reading about Gary Silver SM#335 Liahona, Mike Gough SM 378,
Mike Ondra SM#240 Aletes about their Exhaust Mixing Elbow
(and Exhaust manifold) being blocked with carbon build up, I
decided to purchase a spare Exhaust Mixing Elbow, several
Exhaust gaskets, and change mine as preventive maintenance,
having 2014 hours on the Onan generator.  

For the new owners like myself who are intimidated by new
maintenance they have not performed yet, I illustrated the
“Exhaust Elbow Replacement” on the Onan generator. 

Please do not hesitate to comment, especially if I made
error, as this can only be beneficial for our group.  

I can already say that re-reading Gary’s email on Feb 12,
2016, I forgot to add a thin coat of Permatex High
Temperature RTV…  

Here is the link:

For low bandwidth user, the document is split in 6 sections.

If bandwidth is not an issue, there is also the full version
(37 pictures).  

Sincerely, Alexandre


Club Nautico de San Juan, Puerto Rico

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