Exhaust flange pipe has cracked

[Wes]

I need information regarding the best way to handle my exhaust problem.

The metal pipe threaded into the exhaust manifold flange has cracked creating an exhaust leak in the cabin. I have been unable to get the exhaust flange bolts to turn so I can get the flange and pipe from the manifold. I have sprayed the bolts with liquid wrench etc. I also can not get a socket on them only a open end wrench.....Any thoughts?

I guess I could cut the pipe and remove the exhaust manifold and take it home and work on it.

Anyway, what type of pipe should I use when replacing the old one?

The pipe had about a 1/2" of cloth heat tape over it, is there any type of double walled mulfer pipe instead of the heat tape?

Thanks for any help, Wes

[roadnsky]

Anyway, what type of pipe should I use when replacing the old one?

The pipe had about a 1/2" of cloth heat tape over it, is there any type of double walled mulfer pipe instead of the heat tape?s

Wes-
The pipe you use for the HOT SECTION of your exhaust is 1-1/4" Galvanized pipe. (Available at any hardware store)
Since one section of your exhaust has corroded enough to leak you'll likely have other bad spots too. I would suggest replacing the entire hot section.
There are lots of posts on this site with instructions and tips (search Exhaust Hot Section) but here is a good one http://www.moyermarine.com/forums/sh...xhaust+section to get the juices started.

MMI sells an Exhaust Wrap Kit (Product No. - EXHT_01.0_455) that works great to finish the project.
Just go to their online store under EXHAUST and shop. (Or better yet, call Ken and discuss it with him)

As far as busting loose the flange bolts, I'd suggest using PB BLASTER as I've had better luck with it than Liquid Wrench. Also for the really tough bolt, try some heat too. A squirt of Blaster, tap the bolts a few times, another squirt, go shop for your pipe, come back try it again. Damn! More Blaster, heat, taps... (Beer break here) ...try again. You get the idea.
And yes, you can cut the pipe and take the manifold home to do this if you want.
Post again to let us know how it goes...
-Jerry

[Wes]

Wes-
The pipe you use for the HOT SECTION of your exhaust is 1-1/4" Galvanized pipe. (Available at any hardware store)
Since one section of your exhaust has corroded enough to leak you'll likely have other bad spots too. I would suggest replacing the entire hot section.
There are lots of posts on this site with instructions and tips (search Exhaust Hot Section) but here is a good one http://www.moyermarine.com/forums/sh...xhaust+section to get the juices started.

MMI sells an Exhaust Wrap Kit (Product No. - EXHT_01.0_455) that works great to finish the project.
Just go to their online store under EXHAUST and shop. (Or better yet, call Ken and discuss it with him)

As far as busting loose the flange bolts, I'd suggest using PB BLASTER as I've had better luck with it than Liquid Wrench. Also for the really tough bolt, try some heat too. A squirt of Blaster, tap the bolts a few times, another squirt, go shop for your pipe, come back try it again. Damn! More Blaster, heat, taps... (Beer break here) ...try again. You get the idea.
And yes, you can cut the pipe and take the manifold home to do this if you want.
Post again to let us know how it goes...
-Jerry

Thanks Jerry, I have never heard of Pb Blaster? Auot parts store or local hardware store? I have a butane tourch for sweating copper I guess that would heat it up enough. Thanks again! Wes

[Wes]

Wes-
The pipe you use for the HOT SECTION of your exhaust is 1-1/4" Galvanized pipe. (Available at any hardware store)
Since one section of your exhaust has corroded enough to leak you'll likely have other bad spots too. I would suggest replacing the entire hot section.
There are lots of posts on this site with instructions and tips (search Exhaust Hot Section) but here is a good one http://www.moyermarine.com/forums/sh...xhaust+section to get the juices started.

MMI sells an Exhaust Wrap Kit (Product No. - EXHT_01.0_455) that works great to finish the project.
Just go to their online store under EXHAUST and shop. (Or better yet, call Ken and discuss it with him)

As far as busting loose the flange bolts, I'd suggest using PB BLASTER as I've had better luck with it than Liquid Wrench. Also for the really tough bolt, try some heat too. A squirt of Blaster, tap the bolts a few times, another squirt, go shop for your pipe, come back try it again. Damn! More Blaster, heat, taps... (Beer break here) ...try again. You get the idea.
And yes, you can cut the pipe and take the manifold home to do this if you want.
Post again to let us know how it goes...
-Jerry

Jerry,
I have another question, I looked up the post you said and found a drawing from Don on the exhaust. (To prevent hydrostatic flow through the engine from filling your exhaust) Shows a ANTI-SIPHON valve and also stats to always keep your through haul closed. I never close my through haul? And it does not have this anti-siphon valve. How important are these two issues?
Thanks, Wes

[roadnsky]

Thanks Jerry, I have never heard of Pb Blaster? Auot parts store or local hardware store? I have a butane tourch for sweating copper I guess that would heat it up enough. Thanks again! Wes

Auto Parts store for sure. Hardware store maybe.
The torch will work. You don't need much heat. BE CAUTIOUS around the carb! Be sure to vent the compartment really well.

[roadnsky]

Jerry,
I have another question, I looked up the post you said and found a drawing from Don on the exhaust. (To prevent hydrostatic flow through the engine from filling your exhaust) Shows a ANTI-SIPHON valve and also stats to always keep your through haul closed. I never close my through haul? And it does not have this anti-siphon valve. How important are these two issues?
Thanks, Wes

Wes-
Both issues are important. Closing the Thru Hull would be a priority.

The Anti Syphon Valve will depend on your set up in regards to your boat's waterline. (Your mileage may vary)
Here's a few posts that discusses it in some detail...
http://www.moyermarine.com/forums/sh...ht=anti-siphon
http://www.moyermarine.com/forums/sh...highlight=hull

As far as closing the INTAKE Thru-Hull, you should close it anytime your A4 doesn't start within a few cranks to avoid a back up within the exhaust system by over-cranking the engine with the raw water through-hull open. Without the engine running and producing exhaust pressure to move the cooling water out through the exhaust system, water will continue to collect within the system until it reaches a level that enables it to flow back into the manifold. From there, the water has a direct pathway back into the combustion chambers. Bad news!
Here's a discussion and some good info on it from Don...
http://www.moyermarine.com/forums/sh...g+water+intake
Personally I close mine everytime I shut down my engine and open it as soon as she fires up.

Hopefully this helps...

[Wes]

Wes-
Both issues are important. Closing the Thru Hull would be a priority.

The Anti Syphon Valve will depend on your set up in regards to your boat's waterline. (Your mileage may vary)
Here's a few posts that discusses it in some detail...
http://www.moyermarine.com/forums/sh...ht=anti-siphon
http://www.moyermarine.com/forums/sh...highlight=hull

As far as closing the INTAKE Thru-Hull, you should close it anytime your A4 doesn't start within a few cranks to avoid a back up within the exhaust system by over-cranking the engine with the raw water through-hull open. Without the engine running and producing exhaust pressure to move the cooling water out through the exhaust system, water will continue to collect within the system until it reaches a level that enables it to flow back into the manifold. From there, the water has a direct pathway back into the combustion chambers. Bad news!
Here's a discussion and some good info on it from Don...
http://www.moyermarine.com/forums/sh...g+water+intake
Personally I close mine everytime I shut down my engine and open it as soon as she fires up.

Hopefully this helps...

Jerry, and any one else...Now Iam really stumped!!!

So I could not get the flange loose, So I decided to remove the exhaust manifold, So I cut the pipe as close to the flange as I could get....after loosing the nuts one came out as a whole bolt.. I now wish they all did that as there is not enough room to slide the manifold off the bolts before it hits the side wall of the engine compartment....DANG! NOt sure what to do now..Maybe take chissel to the flang bolts and try and cut them off... not much room to swing a hammer though. THis is turning into a nightmare....
I tried to get a pair of vise-grips in between the manifold and engine and turn out the bolts that way...but no luck...Do you have any suggestions ??

[rigspelt]

after loosing the nuts one came out as a whole bolt.. I now wish they all did that as there is not enough room to slide the manifold off the bolts before it hits the side wall of the engine compartment

Those manifold "bolts" are actually studs, am I right about that? See diagram "Exhaust manifold, front outlet" in "Atomic 4 Parts Catalogue". Try http://www.westerbeke.com/Products/p...g.aspx?id=1063 or go to to the Westerbeke main page and find Atomic 4 in the drop down list of products.

With the engine still in our boat, I was able to remove the exhaust flange from the manifold, and then remove the manifold just by removing the nuts and sliding the manifold off the studs, but (a) he cannot remove the flange from the manifold, (b) sounds like one manifold stud has come out already, and (c) he does not have room to slide the manifold off the remaining studs.

You might seek a professional opinion on the following amateur thoughts. Perhaps you can use a stud remover to get the other manifold studs out? (Would http://www.moyermarine.com/cgi-bin/s...ey=TOOL_01_164 work, or is that only for head studs? And if it does work on manifold studs, do you have enough room to fit it?) If removing the studs is an option, perhaps that would allow you to remove the manifold/flange/dry exhaust stump to work on them on the bench? Then (not being a mechanic), I wonder if it is mechanically correct to re-attach the manifold by sliding it into place over the stud holes and then reinserting the manifold studs, followed by the nuts? If this option is OK, then check on stud and nut torque values and whether thread sealants are needed. There are tricks about inserting those manifold studs, as I recall.

[ndutton]

I'd consider fabricating a removable panel on that side of the engine compartment.

Neil

[Wes]

I'd consider fabricating a removable panel on that side of the engine compartment.

Neil

Hi Neil....yes after chatting with other sailors today they all say the same thing. Cutting the side out will enable me to slide the manifold off finish the repairs and then make a new side panel.. I guess in the future I will be able to get at the engine easer....I thought of this when I was working on her..it kind of hurts to have to change things like that....O well... I guess that s what I will be doing on Sunday..

Thanks for the final push!!!!!

Wes

[Wes]

Those manifold "bolts" are actually studs, am I right about that? See diagram "Exhaust manifold, front outlet" in "Atomic 4 Parts Catalogue". Try http://www.westerbeke.com/Products/p...g.aspx?id=1063 or go to to the Westerbeke main page and find Atomic 4 in the drop down list of products.

With the engine still in our boat, I was able to remove the exhaust flange from the manifold, and then remove the manifold just by removing the nuts and sliding the manifold off the studs, but (a) he cannot remove the flange from the manifold, (b) sounds like one manifold stud has come out already, and (c) he does not have room to slide the manifold off the remaining studs.

You might seek a professional opinion on the following amateur thoughts. Perhaps you can use a stud remover to get the other manifold studs out? (Would http://www.moyermarine.com/cgi-bin/s...ey=TOOL_01_164 work, or is that only for head studs? And if it does work on manifold studs, do you have enough room to fit it?) If removing the studs is an option, perhaps that would allow you to remove the manifold/flange/dry exhaust stump to work on them on the bench? Then (not being a mechanic), I wonder if it is mechanically correct to re-attach the manifold by sliding it into place over the stud holes and then reinserting the manifold studs, followed by the nuts? If this option is OK, then check on stud and nut torque values and whether thread sealants are needed. There are tricks about inserting those manifold studs, as I recall.

Hi Jerry,
I guess you could call them studs, However they have threads on each end...So that you can remove them....and the a nut is what holds the manifold firm against the engine......Anyway......
I spent the day racing today in the Governors Cup...24 mile race so I had a chance to chat about it with the crew and captain and the poll was to cut a larger excess panel so that I can remove the manifold and then have better excess in the future...And then Neil replied with the same answer. Even though I was hoping I would not have to go to that extreme...Seem I have no choice....
I let you how it goes.......Wes

[Administrator]

Before you start sawing/drilling, what is the make/model of your boat? Maybe owners of like boats can offer something less dramatic.

[Wes]

Before you start sawing/drilling, what is the make/model of your boat? Maybe owners of like boats can offer something less dramatic.

It is a Catalina 27' 1984....... Yes I would like to not have to cut a new excess panel. But short of pulling the engine or lubricating the studs and flange blots each day for who knows how long and then breaking them off and then having to cut a new hole anyway, because I would have know room too tape cut off clean and then drill and tape out new holes.....I don’t know...I sure would like to go sailing, summer is here and the weather has been great!

But, If any one knows of a different way...that would be cool!

Thanks again, Wes

[Wes]

I got her Off!

LOL....So I was about to cut a new excess panel, had it all laid out. Then for some reason I thought I would try one more time to see how close I could get her. When crouched way down I noticed the Choke cable was in between the Wall and the Manifold only about a 1/16" But I thought maybe that's enough...SO I got to the edge of the threads and gave her a push and the front part of the manifold slide off....All is I had to do then is rock her back and forth and she came off the back stud...Woo wee that was close! Glade I did not give up.. Manifold is home and on my bench and soaking in some blaster....Hopefully I will get the bolts out of the flange now without twisting them off..

Wes

[David Masury]

If by chance the PB blaster (it is great stuff) doesn't do the trick. Here is an option. Cut the studs off close, center punch the remaining stud and drill it out in series of small to just right size drill bits. Then using a 5/16 botton tap, clean out the remaining material. When you go to install the new flange etc. Use never seize or the equivilant.

David