Return to the home page...

Go Back   Moyer Marine Atomic 4 Community - Home of the Afourians > Discussion Topics > General Interest

Reply
 
Thread Tools Display Modes
  #1   IP: 71.200.119.246
Old 04-16-2013, 08:40 PM
Hymodyne's Avatar
Hymodyne Hymodyne is offline
 
Join Date: Feb 2013
Location: Salisbury, MD
Posts: 376
Thanks: 53
Thanked 13 Times in 12 Posts
black iron pipe

Any tricks or methods for tearing down assembled black iron exhaust pipe are appreciated. I have heated one area with mapp gas with no results. There is no rust visible at any of the threaded points.

James
Reply With Quote
  #2   IP: 24.224.152.244
Old 04-16-2013, 08:49 PM
Mo's Avatar
Mo Mo is offline
Afourian MVP
 
Join Date: Jun 2007
Location: Halifax NS,
Posts: 4,470
Thanks: 292
Thanked 411 Times in 272 Posts
Smile Oxygen / acetylene.

For about $20 - $30 you can probably replace the pipe seen in the pic. The thing about exhausts is that the constant heating and cooling causes corrosion on the material...more so than if it was just kept at room temp. The threads seize in pretty good. When I took mine apart it was there a long time and much rougher looking than yours. I used oxygen / acetylene and it came apart. That was a few years back now, and I had one section so rusty that I broke it pulling on it. FWIW.

Edit: Your pipe does look pretty good though....but ??
__________________
Mo

"Odyssey"
1976 C&C 30 MKI

The pessimist complains about the wind.
The optimist expects it to change.
The realist adjusts the sails.
...Sir William Arthur Ward.

Last edited by Mo; 04-17-2013 at 06:32 AM.
Reply With Quote
  #3   IP: 70.89.31.170
Old 04-16-2013, 09:51 PM
hanleyclifford's Avatar
hanleyclifford hanleyclifford is offline
Afourian MVP
 
Join Date: Mar 2010
Posts: 6,978
Thanks: 172
Thanked 280 Times in 226 Posts
It isn't worth the acetylene or the aggravation to take an old hot section apart. A better use would be as a pattern for a complete new section. They rust from the inside out and at the threads.
Reply With Quote
  #4   IP: 173.79.39.190
Old 04-16-2013, 10:28 PM
edwardc's Avatar
edwardc edwardc is offline
Afourian MVP
 
Join Date: Aug 2009
Location: Laurel, MD
Posts: 2,509
Thanks: 153
Thanked 595 Times in 388 Posts
Quote:
Originally Posted by Hymodyne View Post
Any tricks or methods for tearing down assembled black iron exhaust pipe are appreciated. I have heated one area with mapp gas with no results. There is no rust visible at any of the threaded points.

James
Assuming you decide it's worth it to try, soak the threads in Kroil, or 50/50 ATF/Acetone. Then clamp the pipe behind the elbow and hit the elbow (not the pipe) with a hot flame to heat it as fast as possible. You want the elbows to expand more than the pipe, so that means heating them fast so you don't heat the pipe much. Then get pipe wrench on the elbow. It will come off!
__________________
@(^.^)@ Ed
1977 Pearson P-323 "Dolce Vita"
with rebuilt Atomic-4

Reply With Quote
  #5   IP: 96.229.18.9
Old 04-16-2013, 10:48 PM
Dave Neptune Dave Neptune is online now
Afourian MVP, Professor Emeritus
 
Join Date: Jan 2007
Location: Grove, Oklahoma
Posts: 5,035
Thanks: 711
Thanked 1,289 Times in 839 Posts
Lightbulb Rust

James, once those are rused into position they may as well be welded! The rust holds from both sides along the closely fitted taper. Thats why you don't use teflon when building an "exhaust" the rust will seal and hold long after the system fails elsewhere.

Dave Neptune
Reply With Quote
  #6   IP: 24.224.152.244
Old 04-17-2013, 06:31 AM
Mo's Avatar
Mo Mo is offline
Afourian MVP
 
Join Date: Jun 2007
Location: Halifax NS,
Posts: 4,470
Thanks: 292
Thanked 411 Times in 272 Posts
I'd be putting a new one together as well...as mentioned, not worth the aggravation and the threads will be corroded.
__________________
Mo

"Odyssey"
1976 C&C 30 MKI

The pessimist complains about the wind.
The optimist expects it to change.
The realist adjusts the sails.
...Sir William Arthur Ward.
Reply With Quote
  #7   IP: 68.56.139.11
Old 04-17-2013, 08:51 PM
romantic comedy's Avatar
romantic comedy romantic comedy is offline
Afourian MVP
 
Join Date: May 2007
Location: florida
Posts: 1,912
Thanks: 13
Thanked 118 Times in 100 Posts
I am jumping in the boat here too.

What will you do with the pipe, when you get it apart? make another exhaust? I would not do it. Use new!!!
Reply With Quote
  #8   IP: 71.200.119.246
Old 04-17-2013, 09:06 PM
Hymodyne's Avatar
Hymodyne Hymodyne is offline
 
Join Date: Feb 2013
Location: Salisbury, MD
Posts: 376
Thanks: 53
Thanked 13 Times in 12 Posts
new pipe it is...
Reply With Quote
  #9   IP: 24.152.131.153
Old 04-17-2013, 10:09 PM
ndutton's Avatar
ndutton ndutton is offline
Afourian MVP
 
Join Date: May 2009
Location: Torrance, CA
Posts: 9,619
Thanks: 198
Thanked 2,208 Times in 1,425 Posts
James,

Will you be bending the new pipe to match the old exactly?
__________________
Neil
1977 Catalina 30
San Pedro, California
prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others
Reply With Quote
  #10   IP: 71.200.119.246
Old 04-17-2013, 11:26 PM
Hymodyne's Avatar
Hymodyne Hymodyne is offline
 
Join Date: Feb 2013
Location: Salisbury, MD
Posts: 376
Thanks: 53
Thanked 13 Times in 12 Posts
exhaust design

Like everything else, this will be done from scratch. There is no space for the pictured design in my boat. The new design choices would:

1. run pipe directly from the manifold flange at a slightly downward angle towards the bulkhead at the front of the cockpit floor. The insulated hot pipe wold go through the bulkhead above and to the right of the shaft log, facing the rear of the boat. This is a run of about two feet. at this point, just beyond the bulkhead and in the vertical space there I would put my riser and injection point for the engine's water;

imagine a two foot straight run of pipe, then a 90 deg right for eight inches before the 12-15" of riser and water injection. Pretty much what I mocked up at Home Depot, with the pipe right after the manifold flange a full two feet instead of three inches
after this, I have to decide where to locate the waterlift muffler and the exhaust thru hull.

2. this version omits the riser entirely. The manifold sits above the water line, but only by an inch or so. Because the straight run of pipe goes directly under the cockpit floor, I would like to maintain the downward slope started at the manifold, to avoid any undue heating of the fiberglass floor unederlay.The downward sloping hot exhaust pipe would have the water injected a foot or so down the length of the insulated pipe, aiming towards the stern of the boat in the pipe. A section of exhaust hose would then connect the waterlift muffler to this wet exhaust hose. A loop or riser could be created for the wet exhaust hose after it exits the waterlift muffler.

Thoughts will as always, be appreciated.

James

Last edited by Hymodyne; 04-17-2013 at 11:29 PM.
Reply With Quote
  #11   IP: 173.79.39.190
Old 04-18-2013, 07:34 PM
edwardc's Avatar
edwardc edwardc is offline
Afourian MVP
 
Join Date: Aug 2009
Location: Laurel, MD
Posts: 2,509
Thanks: 153
Thanked 595 Times in 388 Posts
James,
Here's some thoughts.

Your riser design is bulletproof, but there are two caveats:

1) Its a lot of weight. Too much to hang off of the exhaust flange. You'll need to get a couple of pipe hangers to support it.

2) Make sure to insulate the hell out of that long hot section! If you don't, all that heat eventually finds its way back into the cabin, making it very unpleasant in our humid Chesapeake summers!

If you go with the riserless solution, it sounds like your water injection point will be below the waterline. In this case it is absolutely critical that you insert a siphon-break valve in the water line before the injection point. Locate it as high as possible, in a place that will remain above the waterline at all angles of heel.

I would not recommend a loop in the exhaust hose after the waterlift muffler. Exhaust hoses are large diameter and stiff, requiring a large loop diameter. That would trap a large volume of water, with an attendant increase in exhaust backpressure, which is not desirable.

Instead, take the exhaust hose from the waterlift as straight up as you can manage, to a high point above the waterline, and then slope downhill all the way to the stern, with the through-hull exiting at a point that will always remain above the waterline.
__________________
@(^.^)@ Ed
1977 Pearson P-323 "Dolce Vita"
with rebuilt Atomic-4


Last edited by edwardc; 04-18-2013 at 07:36 PM.
Reply With Quote
  #12   IP: 68.99.140.224
Old 04-18-2013, 08:42 PM
zellerj zellerj is offline
Afourian MVP
 
Join Date: May 2005
Posts: 304
Thanks: 5
Thanked 115 Times in 69 Posts
Why replace it

I guess I don't understand why you want to replace it. From the picture in post 1 it appears to be in pretty good shape. It may have quite a few good years left in it.

Best,
Jim
__________________
Jim Zeller
1982 Catalina 30
Kelleys Island, Ohio
Reply With Quote
  #13   IP: 71.200.119.246
Old 04-18-2013, 09:11 PM
Hymodyne's Avatar
Hymodyne Hymodyne is offline
 
Join Date: Feb 2013
Location: Salisbury, MD
Posts: 376
Thanks: 53
Thanked 13 Times in 12 Posts
fit

Quote:
Originally Posted by zellerj View Post
I guess I don't understand why you want to replace it. From the picture in post 1 it appears to be in pretty good shape. It may have quite a few good years left in it.

Best,
Jim
It came with the engine and absolutely does not fit in the spaces I have available for exhaust components.

I'd love to sell it, the minister of finance would like that

Ed, good advice, many thanks. I will probably install a riser and therefore have a two foot run of hot pipe, followed by a runs of eight, twelve, and four inch nipples, the parts of the riser before water injected, which will also need to be properly insulated and supported. Hangers? around the insulation, or around the pipe itself?


James
Reply With Quote
  #14   IP: 173.79.39.190
Old 04-19-2013, 12:55 AM
edwardc's Avatar
edwardc edwardc is offline
Afourian MVP
 
Join Date: Aug 2009
Location: Laurel, MD
Posts: 2,509
Thanks: 153
Thanked 595 Times in 388 Posts
Quote:
Originally Posted by Hymodyne View Post
... Hangers? around the insulation, or around the pipe itself?

James
I was thinking around the pipe, but I suppose either would work.
Something like this or one of these.
__________________
@(^.^)@ Ed
1977 Pearson P-323 "Dolce Vita"
with rebuilt Atomic-4

Reply With Quote
  #15   IP: 71.200.119.246
Old 04-23-2013, 05:04 PM
Hymodyne's Avatar
Hymodyne Hymodyne is offline
 
Join Date: Feb 2013
Location: Salisbury, MD
Posts: 376
Thanks: 53
Thanked 13 Times in 12 Posts
exhaust system

Got a little work done on the exhaust system today. picked up the T with a 1/2 reduction for the water injection, and finished installing the pipe and the loop:


the entire length of pipe from the flange on will get wrapped in muffler wrap.
I haven't found a place for the waterlift muffler yet.

suggestions as to where I should put it in relation to the rest of the system and the water line would be appreciated.

James
Reply With Quote
  #16   IP: 107.0.6.242
Old 04-23-2013, 09:50 PM
hanleyclifford's Avatar
hanleyclifford hanleyclifford is offline
Afourian MVP
 
Join Date: Mar 2010
Posts: 6,978
Thanks: 172
Thanked 280 Times in 226 Posts
Talking

Having gone thru the bulkhead aft of the cockpit well it seems that the pipe must turn 90 degrees up and rise as far as boat configuration will permit. Also, if you can get away with it, a 45 degree angle down to the waterlift is preferred to a 90. The water lift should rest on the hull and the water be injected about 8" above the waterlift. The exhaust pipe to transom should rise as smoothly as possible to a position as high as possible under the poop deck and then descend to the exhaust thru hull; one continuous rise, one descent.
Reply With Quote
  #17   IP: 107.0.6.242
Old 04-23-2013, 09:57 PM
hanleyclifford's Avatar
hanleyclifford hanleyclifford is offline
Afourian MVP
 
Join Date: Mar 2010
Posts: 6,978
Thanks: 172
Thanked 280 Times in 226 Posts
Talking

As has been mentioned you will need one good support for that exhaust structure. Perhaps a cobbled heat proof shock absorbing "grommet" right at that bulkhead, or if you are nervous about that perhaps a "pillow block bearing" style support just forward of the bulkhead? (Remember the old "muffler bearing" joke?
Reply With Quote
  #18   IP: 71.200.119.246
Old 04-24-2013, 09:21 PM
Hymodyne's Avatar
Hymodyne Hymodyne is offline
 
Join Date: Feb 2013
Location: Salisbury, MD
Posts: 376
Thanks: 53
Thanked 13 Times in 12 Posts
[QUOTE=hanleyclifford;67057]Having gone thru the bulkhead aft of the cockpit well it seems that the pipe must turn 90 degrees up and rise as far as boat configuration will permit. Also, if you can get away with it, a 45 degree angle down to the waterlift is preferred to a 90. The water lift should rest on the hull and the water be injected about 8" above the waterlift. The exhaust pipe to transom should rise as smoothly as possible to a position as high as possible under the poop deck and the]

This would have the waterlift sitting at an angle; should I shim one side of the muffler base so that I can install the muffler in an upright position when the boat is on an even keel?
Reply With Quote
  #19   IP: 107.0.6.242
Old 04-24-2013, 10:40 PM
hanleyclifford's Avatar
hanleyclifford hanleyclifford is offline
Afourian MVP
 
Join Date: Mar 2010
Posts: 6,978
Thanks: 172
Thanked 280 Times in 226 Posts
[QUOTE=Hymodyne;67111]
Quote:
Originally Posted by hanleyclifford View Post
Having gone thru the bulkhead aft of the cockpit well it seems that the pipe must turn 90 degrees up and rise as far as boat configuration will permit. Also, if you can get away with it, a 45 degree angle down to the waterlift is preferred to a 90. The water lift should rest on the hull and the water be injected about 8" above the waterlift. The exhaust pipe to transom should rise as smoothly as possible to a position as high as possible under the poop deck and the]

This would have the waterlift sitting at an angle; should I shim one side of the muffler base so that I can install the muffler in an upright position when the boat is on an even keel?
The water lift should be level; create a perch of some kind for it. Here's mine:

Last edited by hanleyclifford; 07-13-2016 at 08:32 PM.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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 Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
welding black iron pipe Hymodyne General Interest 13 03-25-2013 12:34 AM
Black iron or Stainless or brass for exhaust?? romantic comedy Exhaust System 13 02-13-2012 04:34 PM
Where did you get 1-1/4" black iron pipe and fittings? ILikeRust Exhaust System 11 10-03-2011 08:26 AM
Hot Pipe Material Redux ndutton Exhaust System 17 02-25-2011 03:49 PM
Exhaust flange pipe has cracked Wes Troubleshooting 16 06-21-2009 02:55 PM


All times are GMT -4. The time now is 08:03 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.


Universal® is a registered trademark of Westerbeke Corporation

Copyright © 2004-2024 Moyer Marine Inc.

All Rights Reserved