Clogged Yanmar mixing elbow? - Page 2 - SailNet Community
 17Likes
Reply
 
LinkBack Thread Tools
post #11 of 19 Old 12-05-2013
Senior Member
 
christian.hess's Avatar
 
Join Date: Sep 2013
Location: Columbus, Ga
Posts: 4,589
Thanks: 189
Thanked 190 Times in 185 Posts
Rep Power: 3
 
Re: Clogged Yanmar mixing elbow?

yup shops "boil them" if its cheap to do won there like here I would do that...however you can do the rest yourself using vinegar...
christian.hess is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #12 of 19 Old 12-06-2013 Thread Starter
Senior Member
 
Join Date: Oct 2007
Location: Brazil
Posts: 1,039
Thanks: 3
Thanked 24 Times in 23 Posts
Rep Power: 9
 
Re: Clogged Yanmar mixing elbow?

Thanks for the tips everyone. I still plan on replacing the elbow because the welds look a little rusty and it is probably time anyway (2,500 hours). I'll clean up the old elbow and put it in the "spares" kit.
christian.hess likes this.

Vindö 50
copacabana is offline  
Quote Quick Reply Share with Facebook
post #13 of 19 Old 12-06-2013
Senior Member
 
christian.hess's Avatar
 
Join Date: Sep 2013
Location: Columbus, Ga
Posts: 4,589
Thanks: 189
Thanked 190 Times in 185 Posts
Rep Power: 3
 
Re: Clogged Yanmar mixing elbow?

now thats some smart thinking, fix your current stuff to act as working spares...kind of a sailors motto
copacabana likes this.
christian.hess is offline  
Quote Quick Reply Share with Facebook
post #14 of 19 Old 12-06-2013
DrB
Senior Member
 
Join Date: Mar 2007
Location: New England
Posts: 966
Thanks: 0
Thanked 7 Times in 7 Posts
Rep Power: 10
 
Yanmar Mix Elbow

I started to see a lot of black/brown soot when revving by motor so it determined it could be 1 or 2 things:
  1. Injectors were becoming clogged and therefore needed to be pulled and cleaned or
  2. Exhaust elbow was clogged with soot.

At first I was not looking forward to pull the whole exhaust portion of the motor off, but it is super simple and can be done in about 15 min if easy access. Disconnect the cooling water hose from the mixing elbow and then disconnect the whole piece of the exhaust manifold (mixing and exhaust elbows) from the motor by removing the 4 bolts.

I took mine home, separated the exhaust elbow from the mixing elbow, removed as much scale as I could with flat head screw driver, then soaked the both pieces overnight in vinegar.

Thoroughly rinsed and check flow through each with a stream of water. Reassembled, put on a new exhaust gasket and then put everything back together.

Fired up motor and black/brown smoke was gone.

My elbow is original to the motor, 1992, but my motor only has 700 h.
Faster and christian.hess like this.

If you liked my advice/response, give me some rep points. If you didn't......well what do you expect, it was free.
DrB is offline  
Quote Quick Reply Share with Facebook
post #15 of 19 Old 04-25-2016
Junior Member
 
Join Date: Apr 2016
Location: Dublin, Ireland
Posts: 3
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Clogged Yanmar mixing elbow?

Hi All (even though it's 3 years since the last post!).
I have a Yanmar 3GMD and recently noticed a deterioration in engine performance. There was a lot of black smoke and occasionally, a black inky trail in the water. Eventually, it worsened to the point that, 2 weeks ago it would only idle.

It turned out that the outlet from the exhaust manifold was completely clogged to the point that I don't understand how the engine ran at all - let alone how the black smoke even made it out of the exhaust.

It wasn't just blocked with carbon - there was a hard rust formation which had, over time, almost completely clogged it.

I took off the manifold and cleared out the offending port and brought the part to a local machine shop to have the flange face refinished.

In my case the elbow isn't an elbow at all but just a short pipe with a flange which connects to the exhaust manifold block (with gasket in between).

Once all reassembled the engine ran like a dream. It had been slowly choked to death by an ever decreasing means of exhalation. From now on it's now on my list of things to check every 2 years.

BTW the engine is 32 years old and I suspect this had never been looked at previously!

Chris.
chrish0001 is offline  
Quote Quick Reply Share with Facebook
post #16 of 19 Old 04-25-2016
Daniel - Norsea 27
 
Rhapsody-NS27's Avatar
 
Join Date: Apr 2012
Location: Me: VA Boat: Deale, MD
Posts: 891
Thanks: 83
Thanked 38 Times in 33 Posts
Rep Power: 5
 
Re: Clogged Yanmar mixing elbow?

I had a lot of carbon and rust buildup. I recently replaced mine as I think it was still original.

Did a top end rebuild of my 2GM while I was at it.


Daniel
1981 Nor'sea 27,
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Quote:
“Who is staring at the sea is already sailing a little.”
-Paul Carvel

Last edited by Rhapsody-NS27; 04-25-2016 at 07:28 AM.
Rhapsody-NS27 is offline  
Quote Quick Reply Share with Facebook
post #17 of 19 Old 04-25-2016
Junior Member
 
Join Date: Apr 2016
Location: Dublin, Ireland
Posts: 3
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Clogged Yanmar mixing elbow?

Hi Daniel,
In my case it was the exhaust manifold port that was completely blocked. The pipe connecting to it (with the coolant water inlet) was fine. I'm not sure why this was the case.

See photos (1) as it was when I first discovered it and (2) after cleaning out and refinishing the flange.

Chris.
Attached Thumbnails
Endview on Boat (4).jpg   Endview After (5).jpg  
Rhapsody-NS27 likes this.
chrish0001 is offline  
Quote Quick Reply Share with Facebook
post #18 of 19 Old 04-25-2016
Daniel - Norsea 27
 
Rhapsody-NS27's Avatar
 
Join Date: Apr 2012
Location: Me: VA Boat: Deale, MD
Posts: 891
Thanks: 83
Thanked 38 Times in 33 Posts
Rep Power: 5
 
Re: Clogged Yanmar mixing elbow?

Quote:
Originally Posted by chrish0001 View Post
Hi Daniel,
In my case it was the exhaust manifold port that was completely blocked. The pipe connecting to it (with the coolant water inlet) was fine. I'm not sure why this was the case.

See photos (1) as it was when I first discovered it and (2) after cleaning out and refinishing the flange.

Chris.

Wow! that's ugly.
Odd that the pipe was fine, but seeing that the manifold was blocked, maybe the pipe was installed while there was still an opening in the manifold and just not cleaned out by a previous owner.... Just "thinking out loud".

But really good that you fixed that. Could have caused much more problems.

Just shows that engine maintenance goes beyond changing oil and filters.

With all the work I did to my engine, I'm thinking a regular inspection of the head and cooling passages is a good idea too.
Good job, Chris!

Daniel
1981 Nor'sea 27,
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Quote:
“Who is staring at the sea is already sailing a little.”
-Paul Carvel
Rhapsody-NS27 is offline  
Quote Quick Reply Share with Facebook
The Following User Says Thank You to Rhapsody-NS27 For This Useful Post:
chrish0001 (04-25-2016)
post #19 of 19 Old 04-25-2016
Junior Member
 
Join Date: Apr 2016
Location: Dublin, Ireland
Posts: 3
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Clogged Yanmar mixing elbow?

Hey Daniel.
That's a good theory. It's not possible to see the exhaust port when you take off the "elbow" pipe (or 45 degree pipe in my case). You can only see into the pipe you've just removed. The last time someone possibly looked at this was in the days before smart phones - with cameras - allowed you see around corners and make videos of out-of-the-way places in your engine. This is what I did to discover the ugly truth behind my fading engine!

Thanks for your comments!

Chris.
Rhapsody-NS27 likes this.
chrish0001 is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Yanmar 2GM20F mixing elbow Pearson 31-2 Neo* Pearson 12 01-12-2014 12:55 AM
Another Yanmar Exhaust Mixing-Elbow Question saildork Diesel 6 01-13-2013 01:28 PM
Yanmar mixing elbow rchad Diesel 3 05-02-2010 05:56 PM
Mixing elbow trantor12020 Gear & Maintenance 10 09-27-2008 07:29 AM
Clogged Exhaust or Mixing Elbow: Clean or Replace? oft Gear & Maintenance 18 07-18-2008 03:55 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome