Separating exhaust tubes

[Greg Ellis]

Wasn’t quite sure where to post this but any tricks on separating parts of the exhaust at the various joints?  I’ve got one that is stuck together and cannot seem to get them separated.  It is at the joint where the horizontal part of the exhaust curves up to go into the #4 cylinder (O-360).  There is a joint there but it is stuck together tight.  I tried to see if some mouse milk would wick in the joint but no luck.  Any thoughts?  Thank you.

[N201MKTurbo]

With the whole thing off the plane, get about a 2’x2’ piece of plywood. Set the stuck riser flat on the plywood and mark the bolt holes with a pencil. Move the exhaust and drill two 5/16 holes. Get two 5/16 nut and bolts and bolt the riser to the plywood. Grab the muffler and try to twist it off while standing on the plywood. If it is still stuck, try lots of mouse milk, heat and a cheater bar in one of the other riser joints. Don’t tear up your muffler. 
 

Before you put it back together, sand the inside and outside of the joint with 800 sandpaper. Use anti-seise to lube it.  

[47U]

39 minutes ago, Greg Ellis said:

There is a joint there but it is stuck together tight.

AeroKroil.  Give it time to work, overnight or a couple days.  You can also try heating up the outside tube with a heat gun, after an overnight with the AeroKroil treatment.

As @N201MKTurbo suggested, before putting it back together, clean it up and use the proper anti-sieze.  I think something without graphite is recommended, but you should probably verify that.

[Fly Boomer]

54 minutes ago, Greg Ellis said:

Wasn’t quite sure where to post this but any tricks on separating parts of the exhaust at the various joints?  I’ve got one that is stuck together and cannot seem to get them separated.  It is at the joint where the horizontal part of the exhaust curves up to go into the #4 cylinder (O-360).  There is a joint there but it is stuck together tight.  I tried to see if some mouse milk would wick in the joint but no luck.  Any thoughts?  Thank you.

When you put it back together, try this stuff

https://www.mcfarlaneaviation.com/products/DAM20-4--0/

We used it on mine, but it will be awhile before I know if it worked.

[EricJ]

3 hours ago, Fly Boomer said:

When you put it back together, try this stuff

https://www.mcfarlaneaviation.com/products/DAM20-4--0/

We used it on mine, but it will be awhile before I know if it worked.

Same here.   I just put mine back together and lubed it generously with this stuff.    It also indicates that it can be used to un-stuck a stuck piece, and I'm letting it wick into one joint that was stuck with periodic application to see if that works.

 

[Fly Boomer]

9 minutes ago, EricJ said:

Sadme here.   I just put mine back together and lubed it generously with this stuff.    It also indicates that it can be used to un-stuck a stuck piece, and I'm letting it wick into one joint that was stuck with periodic application to see if that works.

 

After I posted that link to McFarlane, I went back and read their web, and noticed that it could be used to loosen stuck pipes.  Maybe I'll do some prophylactic "un-seizing" every oil change.

[PT20J]

13 hours ago, Fly Boomer said:

After I posted that link to McFarlane, I went back and read their web, and noticed that it could be used to loosen stuck pipes.  Maybe I'll do some prophylactic "un-seizing" every oil change.

I’m trying that. The fluid has about the viscosity of water and seems to soak into the joints. It leaves a white residue behind after it heats up, so hopefully some of that gets down into the joints. I’ve got about 600 hrs on the muffler, so I may be needing to take it apart in a few hundred more for an overhaul.