Jump to content

Recommended Posts

Posted

Hey all,

So my 28-year-old (but 500-hr) TSIO-360-MB1 is in annual, and there's corrosion on the cams and lifters (see pics).  I am TCM SIB 05-1 aware.

Posting here for you to share your thoughts. Have you had cam corrosion on your Mooney?  Or worked on them?  How does this compare with what you've seen?

Jason

 

IMG_7123.JPG

IMG_7124.JPG

IMG_7125.JPG

IMG_7126.JPG

Posted

Nice pics, NatWide!

Of those 500, How many hours have you put on it this year?

What does the oil filter and screens look like?

When the similar Lycoming cam challenge occurs... the roughened lifters cut into the cam lobes, once the hardened surface is eroded...

The lobes get cut down quickly at that point and all the metal bits show up in the filter.

That much metal deposits all over the place and gets imbedded in places it doesn't belong...

 

being familiar with the cam SB, what's your thoughts of pulling the cam and lifters?

Consider editing the title of this thread to include the word Continental...

 

PP thoughts only, not a mechanic.

Best regards,

-a-

Posted

If it isn't shedding metal yet, it will soon.  The cylinders likely look similar.

Better to fix it before it contaminated the rest of the engine.

Clarence

Posted

500 hrs / 28 yrs = 17.8 hrs / yr. that would explain why. I assume it sat for a number of years too - perhaps right before you bought it too? Hopefully you bought discounted as a run out engine. Still very unfortunate but hopefully you are prepared to major it. Bummer!

 

 

Sent from my iPhone using Tapatalk

Guest paulie
Posted

At least borescope the cylinders. Hope the crank is not like this, that gets expensive.

Posted
8 hours ago, jetdriven said:

WHat kind of oil were you using and did you use camguard?  500 hours over 28 years is vastly underused. 

I use AS 15W-50 all season. PO used that and also P 20W-50.  I have not used Camguard. Don't know if the PO did or not.  Clearly it has not spent a lot of its time flying.

Posted
8 hours ago, carusoam said:

Nice pics, NatWide!

Of those 500, How many hours have you put on it this year?

What does the oil filter and screens look like?

When the similar Lycoming cam challenge occurs... the roughened lifters cut into the cam lobes, once the hardened surface is eroded...

The lobes get cut down quickly at that point and all the metal bits show up in the filter.

That much metal deposits all over the place and gets imbedded in places it doesn't belong...

 

being familiar with the cam SB, what's your thoughts of pulling the cam and lifters?

Consider editing the title of this thread to include the word Continental...

 

PP thoughts only, not a mechanic.

Best regards,

-a-

The oil analyses have been decent. Some very good but an occasional one with elevated iron; usually after a period of disuse.  No appreciable metals in the screens or filter.

Sadly I've only put on 38 in the past 12 months but 15 have been in the last 3 weeks.

The SB seems to allow some cam lobe corrosion as long as it is not cracking.  Apparently it's not a terrible job on the TCMs to pull lifters. The camshaft is a different story of course. My A&P has said he is "concerned" about the amount of corrosion but I haven't spoken to him yet, only got his email with the pics.

I am getting the rest borecoped but haven't heard the results.  Due to the age of the engine and some other issues I've dealt with unrelated to the cams I'm leaning towards throwing in a factory reman and treating the thing right (flying frequently) right off the bat.

I'm on my iPhone...didn't see a way to change the thread title...you're right--that would've been helpful.

Posted
4 hours ago, Mooney_Mike said:

28 years old with internal corrosion?  I would get it overhauled, but that's just me.

I had a cam making metal and did the same 6 months ago.

The corrosion on the cam and lifters means it will start shedding metal which will ruin your prop gov, oil cooler, turbo...it's all bad.

 

What did your cams look like when they started failing?

Posted
6 hours ago, Dream to fly said:

Any chance that can be converted to a roller assembly.  now would be the time for sure. 

Why in the world would you want to do this?  just put the extra money into gas and fly it.  The corrosion is there because it sat and lack of use.  

Posted
Why in the world would you want to do this?  just put the extra money into gas and fly it.  The corrosion is there because it sat and lack of use.  
Those mating surfaces are corroded. They will not glide past each other smoothly without causing metal wear. This in turn will damage a lot of other components. When parts fail I always go for the best replacement possible. Roller cams are a million times better that flat tappet. As posted earlier that is not possible so a direct replacement would be best. As for flying it who would when Kodak proved there is a problem.

Sent from my E6810 using Tapatalk

  • Like 2
Posted
Roller cams are a million times better that flat tappet.

 

A million? So the TBOs of the new engines are 2 billion hours now?

IMHO: the weak spot is corrosion of the cam in aircraft engines, I wish they made a replacement cam out of titanium.

I don't think rollers, chromed/nickled cylinders are going to prevent this, but possibly a pre oiler could help, especially if it was run periodically.

Posted
A million? So the TBOs of the new engines are 2 billion hours now?
IMHO: the weak spot is corrosion of the cam in aircraft engines, I wish they made a replacement cam out of titanium.
I don't think rollers, chromed/nickled cylinders are going to prevent this, but possibly a pre oiler could help, especially if it was run periodically.
I never said roller cams prevent what happened. But they are far superior in design. Lack of use and no oil film caused it. My thought was if you are going to replace the cam could a better design be installed. If we really want to split hairs roller cams suck too. Electronic solenoids would be best.


Sent from my E6810 using Tapatalk

Posted
1 hour ago, teejayevans said:

A million? So the TBOs of the new engines are 2 billion hours now? emoji6.png

IMHO: the weak spot is corrosion of the cam in aircraft engines, I wish they made a replacement cam out of titanium.

I don't think rollers, chromed/nickled cylinders are going to prevent this, but possibly a pre oiler could help, especially if it was run periodically.

Rollers won't prevent corrosion but they eliminate spalling. Spalling is from sliding friction. Rollers don't slide. 

  • Like 2
Posted
2 minutes ago, peevee said:

If nickel works for cylinder walls you'd think it would work for cams too. Guess not or they'd be doing it already.

Cranks and Cams are nitrided, which is a hardening process. I have no idea but I'm guessing nickel wouldn't last long on a cam.

Posted
1 minute ago, N6758N said:

Cranks and Cams are nitrided, which is a hardening process. I have no idea but I'm guessing nickel wouldn't last long on a cam.

Dunno. The wear of the rings on the walls might be less or might be more. I'm sure some folks will be by shortly to argue about it. Either way, that sucks for the threadstarter.

  • Like 1
Posted
18 hours ago, nationwide said:

Hey all,

So my 28-year-old (but 500-hr) TSIO-360-MB1 is in annual, and there's corrosion on the cams and lifters (see pics).  I am TCM SIB 05-1 aware.

Posting here for you to share your thoughts. Have you had cam corrosion on your Mooney?  Or worked on them?  How does this compare with what you've seen?

Jason

 

 

 

Nice pictures ..... just wondering why you opened engine in the first place. Or were these taken with a borescope ? if they were what kin of borescope was it. I want one. 

  • Thanks 1
Posted

NatWide,

Take a look at the second picture that MooneyMike posted...

there is a lot of detail.  What stands out is the lunar surface of the cam follower that is pointed towards the camera.

the cam followers pointed away from the camera aren't very helpful...

 

See if you can get a picture of your cam follower's surfaces.

If they are lunar like, it would be good to know.

 

material selection is a science that requires matching the hardness of two materials so that one wears at a very slow pace compared to the other.   Too much of a difference, is bad.  Too little of a difference is worse.

selecting the materials to match the chemical environment also adds another level of challenge.  The engine builders haven't designed for sitting long periods of time to their environment for design..?

any of the 'guesses' for coating or metals like titanium, have to match the stiffness, hardness, strength, economics,  and chemical  resistance required for the cam.

There are not a lot of  Continental cams suffering from this type of sitting challenge.  They engine has a significant design difference where the cam is located in the engine.  It can sit a little longer than a Lycoming, but not a lot longer....

PP thoughts only. Not a mechanic.

Best regards,

-a-

Posted
3 hours ago, Mooney_Mike said:

Like this... yikes! It was making some serious metal, see pic #3. Also, oil analysis did not show the issue since all the metal particles were caught in the oil filter, so be sure to cut the oil filter open to look for trouble too.

Ouch...those lifter surfaces look really bad. I'm glad the new engine is working out for you!

Posted
16 minutes ago, carusoam said:

NatWide,

Take a look at the second picture that MooneyMike posted...

there is a lot of detail.  What stands out is the lunar surface of the cam follower that is pointed towards the camera.

the cam followers pointed away from the camera aren't very helpful...

 

See if you can get a picture of your cam follower's surfaces.

If they are lunar like, it would be good to know.

Best regards,

-a-

The mech is taking more photos.  I will post what I get.

  • Like 1

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.