Topics

Oil leak - Cylinder Base

Jim Patillo
 

Hey Bruce,

I also have an oil leak I’ve been putting off fixing on #2 and #3 cylinders. I think it’s the thru bolts leaking.
I’ve heard that the leak can be stopped by pulling the cylinder away, pushing the thru bolt out a little, wrapping silk thread around the bolt shaft, pushing back in place  and reinstalling the cylinder.

Please let me know what you found and how you repaired it. 


Regards,
Jim
N46JP - Q200

Bruce Crain
 

YepI  That would be correct on the actual through bolt.  I did the silk thread with thread locker or RTV in the thread. 
I did both left and right ends to keep from leaking on either side.  You will need to pull both 2 and 3 cylinders away from the case halves. 
When you start wrapping the thread just keep wrapping it until it starts to fit snugly.  Then do the other end and make them both fit snugly.  I think I wrapped them at the outer ends but not outside the side of the case.  You don't want to let the thread and locker hold the cylinder away from the case half!  Add the thread locker to the thread and push the through bolt into place.  It should be snug enough to keep it in place but not enough to keep it from going into place.  
When you torque the bolt try to keep the ends fairly symmetrical.
 
My leak has been on the left front side of the case.  There are 2 bolts that thread into the case half on the other side.  I thought I might need to check out the cylinder base flat O ring but D and B Engines said the leak never happens with that base o ring.  He said the 2 bolts are the culprit.  I affirm that as I have seen oil coming out of the threads.
I finished remounting the cylinder and torquing the base nuts and installing the new push tube oil return tubes.  I will most likely finish plumbing the rest this week while Honey Lamb is working.  I get lonesome at the hanger so I came home to "entertain her"!  wink_smile
 
I will shout out loud if I can get this 0200 dry!
 
Bruce Crain 
 

---------- Original Message ----------
From: "Jim Patillo" <Logistics_engineering@...>
To: main@Q-List.groups.io
Subject: [Q-List] Oil leak - Cylinder Base
Date: Sat, 21 Mar 2020 09:57:07 -0700

Hey Bruce,

I also have an oil leak I’ve been putting off fixing on #2 and #3 cylinders. I think it’s the thru bolts leaking.
I’ve heard that the leak can be stopped by pulling the cylinder away, pushing the thru bolt out a little, wrapping silk thread around the bolt shaft, pushing back in place  and reinstalling the cylinder.

Please let me know what you found and how you repaired it. 


Regards,
Jim
N46JP - Q200

Sam Hoskins
 

Jim, also try posting on the https://smallcontinentalengines.groups.io/g/main

Silk thread under the through bolts? I dunno. That sounds like the kind of thing that could cause an issue with maintaining proper torque and lead to the loss of a cylinder.

Maybe Harry Fenton will see it and comment. 

On Sat, Mar 21, 2020, 11:57 AM Jim Patillo <Logistics_engineering@...> wrote:

Hey Bruce,

I also have an oil leak I’ve been putting off fixing on #2 and #3 cylinders. I think it’s the thru bolts leaking.
I’ve heard that the leak can be stopped by pulling the cylinder away, pushing the thru bolt out a little, wrapping silk thread around the bolt shaft, pushing back in place  and reinstalling the cylinder.

Please let me know what you found and how you repaired it. 


Regards,
Jim
N46JP - Q200

Jim Patillo
 

Thanks for the input Bruce and Sam. I will ask on continental engine site. 
Not sure how installing silk thread could change the torque characteristics. Looks like Bruce will be providing an update soon.


Regards,
Jim
N46JP -Q200

Bruce Crain
 

I am sorry I did not explain myself good enough!  None of the thread or locker is to go under the cylinder base bolts or cylinder skirt for the through bolt Jim is talking about!  It is to go inside the hole that the through bolt goes through .  Perhaps an inch or so inside the hole in the case halves!
Bruce 

On Mar 21, 2020, at 11:57 AM, Jim Patillo <logistics_engineering@...> wrote:



Hey Bruce,

I also have an oil leak I’ve been putting off fixing on #2 and #3 cylinders. I think it’s the thru bolts leaking.
I’ve heard that the leak can be stopped by pulling the cylinder away, pushing the thru bolt out a little, wrapping silk thread around the bolt shaft, pushing back in place  and reinstalling the cylinder.

Please let me know what you found and how you repaired it. 


Regards,
Jim
N46JP - Q200

Phil Lankford
 

I am not sure you wouldn’t (double negative?) get a similar positive seal on those threads if you were to just dress them with Hylomar without the silk thread trick. But I’m listening. 

Phil Lankford  


On Mar 21, 2020, at 2:45 PM, Bruce Crain <jcrain2@...> wrote:


YepI  That would be correct on the actual through bolt.  I did the silk thread with thread locker or RTV in the thread. 
I did both left and right ends to keep from leaking on either side.  You will need to pull both 2 and 3 cylinders away from the case halves. 
When you start wrapping the thread just keep wrapping it until it starts to fit snugly.  Then do the other end and make them both fit snugly.  I think I wrapped them at the outer ends but not outside the side of the case.  You don't want to let the thread and locker hold the cylinder away from the case half!  Add the thread locker to the thread and push the through bolt into place.  It should be snug enough to keep it in place but not enough to keep it from going into place.  
When you torque the bolt try to keep the ends fairly symmetrical.
 
My leak has been on the left front side of the case.  There are 2 bolts that thread into the case half on the other side.  I thought I might need to check out the cylinder base flat O ring but D and B Engines said the leak never happens with that base o ring.  He said the 2 bolts are the culprit.  I affirm that as I have seen oil coming out of the threads.
I finished remounting the cylinder and torquing the base nuts and installing the new push tube oil return tubes.  I will most likely finish plumbing the rest this week while Honey Lamb is working.  I get lonesome at the hanger so I came home to "entertain her"!  wink_smile
 
I will shout out loud if I can get this 0200 dry!
 
Bruce Crain 
 

---------- Original Message ----------
From: "Jim Patillo" <Logistics_engineering@...>
To: main@Q-List.groups.io
Subject: [Q-List] Oil leak - Cylinder Base
Date: Sat, 21 Mar 2020 09:57:07 -0700

Hey Bruce,

I also have an oil leak I’ve been putting off fixing on #2 and #3 cylinders. I think it’s the thru bolts leaking.
I’ve heard that the leak can be stopped by pulling the cylinder away, pushing the thru bolt out a little, wrapping silk thread around the bolt shaft, pushing back in place  and reinstalling the cylinder.

Please let me know what you found and how you repaired it. 


Regards,
Jim
N46JP - Q200

Bruce Crain
 

Nothing on the threads.  The thread locker goes in the silk thread around the through bolt.  My mid engine through bolt has been dry for years.  The left two through bolts have not.  Today I hope to finish plumbing everything together for runup then cowl and fly.  Hoping for the best!
Bruce


On Mar 22, 2020, at 10:40 PM, Phil Lankford via Groups.Io <britmcman@...> wrote:

I am not sure you wouldn’t (double negative?) get a similar positive seal on those threads if you were to just dress them with Hylomar without the silk thread trick. But I’m listening. 

Phil Lankford  


On Mar 21, 2020, at 2:45 PM, Bruce Crain <jcrain2@...> wrote:


YepI  That would be correct on the actual through bolt.  I did the silk thread with thread locker or RTV in the thread. 
I did both left and right ends to keep from leaking on either side.  You will need to pull both 2 and 3 cylinders away from the case halves. 
When you start wrapping the thread just keep wrapping it until it starts to fit snugly.  Then do the other end and make them both fit snugly.  I think I wrapped them at the outer ends but not outside the side of the case.  You don't want to let the thread and locker hold the cylinder away from the case half!  Add the thread locker to the thread and push the through bolt into place.  It should be snug enough to keep it in place but not enough to keep it from going into place.  
When you torque the bolt try to keep the ends fairly symmetrical.
 
My leak has been on the left front side of the case.  There are 2 bolts that thread into the case half on the other side.  I thought I might need to check out the cylinder base flat O ring but D and B Engines said the leak never happens with that base o ring.  He said the 2 bolts are the culprit.  I affirm that as I have seen oil coming out of the threads.
I finished remounting the cylinder and torquing the base nuts and installing the new push tube oil return tubes.  I will most likely finish plumbing the rest this week while Honey Lamb is working.  I get lonesome at the hanger so I came home to "entertain her"!  wink_smile
 
I will shout out loud if I can get this 0200 dry!
 
Bruce Crain 
 

---------- Original Message ----------
From: "Jim Patillo" <Logistics_engineering@...>
To: main@Q-List.groups.io
Subject: [Q-List] Oil leak - Cylinder Base
Date: Sat, 21 Mar 2020 09:57:07 -0700

Hey Bruce,

I also have an oil leak I’ve been putting off fixing on #2 and #3 cylinders. I think it’s the thru bolts leaking.
I’ve heard that the leak can be stopped by pulling the cylinder away, pushing the thru bolt out a little, wrapping silk thread around the bolt shaft, pushing back in place  and reinstalling the cylinder.

Please let me know what you found and how you repaired it. 


Regards,
Jim
N46JP - Q200

Bruce Crain
 

After pulling the number 4  cylinder and putting o rings on the front two through bolts I tested it out today.  After the 1st flight the leak was worse!!  I pulled it back into the hanger and pulled the cowling. 
 
The leak was coming from the #4 cylinder!  Piffle!!  But I did notice it was coming from the rocker box cover.  I had reused the silicone gasket and knew that was probably the culprit!  So I pulled the rocker cover and could see a small chunk out of the gasket.  I located the chunk in the tin bucket underneath to catch the oil so I knew it wasn't in the crank case.  I put a  new silicone rocker cover gasket on it and flew it again for about  3 tenth of an hour.  When I looked under the fuz there was not any oil showing!!!!  After all these years I finally have a DRY BELLY!
 
Kevin Boddecker I am still working towards your Spring Fling and this is the biggest fix that needed to be done.  I am also working on a couple of other cosmetics things plus I will continue to up date on my sparrow strainer stall.  I am thinking I need to re-position the zig zag tape further back on the apex of the strainer to see if that works differently.  Will let you know when I get a chance to test that.
 
 Great day to fly!  Not much wind and 68 degrees!
 
What a great airplane!
Bruce Crain 
N96BJ  
 

Jay Scheevel
 

Congrats on getting your leak controlled, Bruce!

 

Cheers,

Jay

 

From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Thursday, March 26, 2020 4:59 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Oil leak - Cylinder Base

 

After pulling the number 4  cylinder and putting o rings on the front two through bolts I tested it out today.  After the 1st flight the leak was worse!!  I pulled it back into the hanger and pulled the cowling. 

 

The leak was coming from the #4 cylinder!  Piffle!!  But I did notice it was coming from the rocker box cover.  I had reused the silicone gasket and knew that was probably the culprit!  So I pulled the rocker cover and could see a small chunk out of the gasket.  I located the chunk in the tin bucket underneath to catch the oil so I knew it wasn't in the crank case.  I put a  new silicone rocker cover gasket on it and flew it again for about  3 tenth of an hour.  When I looked under the fuz there was not any oil showing!!!!  After all these years I finally have a DRY BELLY!

 

Kevin Boddecker I am still working towards your Spring Fling and this is the biggest fix that needed to be done.  I am also working on a couple of other cosmetics things plus I will continue to up date on my sparrow strainer stall.  I am thinking I need to re-position the zig zag tape further back on the apex of the strainer to see if that works differently.  Will let you know when I get a chance to test that.

 

 Great day to fly!  Not much wind and 68 degrees!

 

What a great airplane!

Bruce Crain 

N96BJ