I Think I Found The Source of the CO leak

[alextstone]

I did my first oil change yesterday.  I also installed Tempest fine wire plugs.  Recently, my CO alarm triggered on climb out.  I could even smell exhaust in the cabin.  I recently has the exhaust overhauled, BTW, and the leak began shortly after.  The mechanic who installed the overhauled exhaust re inspected it and gave it his blessing but he could not identify the source of the leak.  The photos are of the plugs and cylinders 1 and 2.

My guess is the person who installed the old plugs last did not change the copper washers as is required.

[N201MKTurbo]

I would suspect that was from the exhaust gasket, not the plug. Was the plug loose when you removed it?

[alextstone]

2 minutes ago, N201MKTurbo said:

I would suspect that was from the exhaust gasket, not the plug. Was the plug loose when you removed it?

No the plugs were not loose.  Thanks.  That makes a lot more sense.  Would you please have a look at my other post regarding a suspected oil leak?  I would appreciate your feed back.  

[LANCECASPER]

5 minutes ago, N201MKTurbo said:

I would suspect that was from the exhaust gasket, not the plug. Was the plug loose when you removed it?

Most of the times plugs are over-torqued, with no anti-sieze on the threads, seemingly installed by a 900 pound gorilla,

[carusoam]

Since you have a Bravo...

And V-bands have their limitations on re-use...

Do you know if the V-bands were new or re-used?

If not, be sure to become familiar with these details...

Turbo exhaust systems take on a higher amount of criticality(?) compared to the NA version...

Best regards,

-a-

[alextstone]

15 minutes ago, carusoam said:

Since you have a Bravo...

And V-bands have their limitations on re-use...

Do you know if the V-bands were new or re-used?

If not, be sure to become familiar with these details...

Turbo exhaust systems take on a higher amount of criticality(?) compared to the NA version...

Best regards,

-a-

Thanks.  The entire exhaust system was overhauled 45 hours ago and the v-bands were replaced at that time.  

[thinwing]

I think Lance is correct..that exhaust deposit is not coming from the plug hole...it’s from the exhaust flange gasket...

[Guest]

On 1/20/2019 at 9:13 AM, alextstone said:

I did my first oil change yesterday.  I also installed Tempest fine wire plugs.  Recently, my CO alarm triggered on climb out.  I could even smell exhaust in the cabin.  I recently has the exhaust overhauled, BTW, and the leak began shortly after.  The mechanic who installed the overhauled exhaust re inspected it and gave it his blessing but he could not identify the source of the leak.  The photos are of the plugs and cylinders 1 and 2.

My guess is the person who installed the old plugs last did not change the copper washers as is required.

As well as the exhaust leak, it looks like the intake tube gasket is leaking, it looks like blue dye on it.

Clarence

[Rick Junkin]

On 1/20/2019 at 2:26 PM, alextstone said:

Thanks.  The entire exhaust system was overhauled 45 hours ago and the v-bands were replaced at that time.  

Hi Alex @alextstone,

Did you check the torque on the exhaust flange nuts after about 10 hours of operation after the exhaust overhaul?

I ask because I had similar exhaust leaks when we changed the exhaust flange gaskets after loosening things up to realign things at the v-band clamps. My mechanic was a little embarrassed that he hadn't thought to re-torque them after I had flown for a bit and everything settled into place. You will want to check the rest of them when you get this squared away, and then check them every 10 hours or so until the torque doesn't change, and then at the next oil change. I'm not a mechanic, just a "been there done that" kind of guy.

Looks like a smoking gun for the cause of your CO problems (really bad pun intended).

Speaking of oil changes - you said that this is your first one since installing overhauling the exhaust 48 hours ago? Or is this the first one that you've done yourself? If its the first one in 48 hours, you've overflown the recommended 25 hours between oil changes for the TIO-540-AF1B. The engine manual says 50 hours, but there is a Lycoming service letter that directs a 25 hour interval. Let me know if you need it and I'll send you a copy.

Cheers,
Rick

[alextstone]

2 hours ago, Junkman said:

Hi Alex @alextstone,

Did you check the torque on the exhaust flange nuts after about 10 hours of operation after the exhaust overhaul?

I ask because I had similar exhaust leaks when we changed the exhaust flange gaskets after loosening things up to realign things at the v-band clamps. My mechanic was a little embarrassed that he hadn't thought to re-torque them after I had flown for a bit and everything settled into place. You will want to check the rest of them when you get this squared away, and then check them every 10 hours or so until the torque doesn't change, and then at the next oil change. I'm not a mechanic, just a "been there done that" kind of guy.

Looks like a smoking gun for the cause of your CO problems (really bad pun intended).

Speaking of oil changes - you said that this is your first one since installing overhauling the exhaust 48 hours ago? Or is this the first one that you've done yourself? If its the first one in 48 hours, you've overflown the recommended 25 hours between oil changes for the TIO-540-AF1B. The engine manual says 50 hours, but there is a Lycoming service letter that directs a 25 hour interval. Let me know if you need it and I'll send you a copy.

Cheers,
Rick

Hi Rick,

 

Yes, the nuts needed to be re torqued...so I think you are right about the source of the leak.  This was the first oil change I did, at 20.2 hours since the last one.  I am doing them every 25 hrs or less as recommended.

 

Alex