Not wanting to be the next Cirrus Engine failure

jesse said:
You know how many mechanics I've seen actually do a compression check on a Continental per their compression SID? Zero.

I wouldn't go replacing cylinders because an A&P says the compression on it is "bad" unless you make for damn sure they're doing it precisely via the SID and that the SID calls for that course of action.
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I'm with Jesse on this one.
Also, if a mechanic calls it a "compression check", he likely doesn't even know how to perform it right. Maybe if he calls it a "leak-down" or "blow-by" test, he might start understanding what he is actually doing with the engine.
But yes, 30/80 numbers sound like a lot of crud on valve seats or even worse, burnt rings. Need to bore-scope the engine first and if it doesn't look good inside, pull the jugs.

Let us know what you find, let's hope they can get the "compression" back into 70's.
 
3 Cylinders removed and taken to a local that was highly recommended.
I was working so I didn't get to go but he suspects valves.

I have no vocabulary for this but I will describe what my father said.
He pulled a bar that goes through the piston out because it was loose.
I have no idea what this is but it was described as a bar that goes laterally through the piston which connects to the arm the piston rides on.
I believe it is called a piston pin.

He pulls this bar out and it is fractured. He gives it a little twist and it comes apart in his hands. :eek:
I am picking the cylinders up Monday and will upload photos of that pin. I am pretty curious about it.

Not sure what would happen if that failed in flight.
 
It's called a wrist pin.

If it fractured it's possibly due to a metallurgical flaw when it was made. And if it came out fractured after the piston was pulled from the cylinder it probably did fail in flight.

I can't make any obvious connection between this problem and "valves" as you mentioned.
 
And as noted, this is not related to the issue I experienced. The thinking is that it is a valve issue. This was just an "in addition to"
 
SixPapaCharlie said:
And as noted, this is not related to the issue I experienced. The thinking is that it is a valve issue. This was just an "in addition to"
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Regardless, it all sounds expensive :( But I have the feeling once it's all bolted back together and in the airplane you'll have more confidence in the powerplant, and that's worth a lot.

We are all interested to find out what turns up as the examination continues.
 
6PC: You may want to upload that to Savvy. I know many here do not like him but many do... He knows his stuff. Otherwise you may want to contact Jim at Aviation Vibes at KUBE - he knows Cirrus better than anyone. He's done work for me and many other SR22 owners...
 
SixPapaCharlie said:
I just signed up over there. Kicking the tires now.
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You will be quite happy you did. They've helped me with 2 planes SR20 and SR22 - they've saved me thousands of dollars. I remember when I sold my SR20 the shop doing the pre-buy said I had 3 bad jugs and all had to be replaced. Savvy was all over it. Savvy was not doing the pre-buy for the buyer but they were on my side as I was selling. After they saw the pictures they called Contenental and a rep from Cont motors called the shop and the new buyer and said the jugs were fine. The guy was ready to walk cause I wasn't changing them... After the buyer talked to Cont he was convinced. Jugs were fine. He bought and plane is still running smooth 400 hours later.

Had I not had Savvy either the plane would not have sold or I would have bought 3 un-needed jugs..
 
As described by the other poster, the item that failed was the wrist pin.

Sooo glad the engine was telling you to it was failing. If that pin had come out in flight, .....

How long before you get the airplane back? 55WB is due back from paint shop soon and I'll be needing a safety pilot if you're available.
 
Wrist pin failure is very bad. Make sure all the pieces are accounted for. I'd check the other cylinders too, the ones not yet removed.
 
PaulS said:
Wrist pin failure is very bad. Make sure all the pieces are accounted for. I'd check the other cylinders too, the ones not yet removed.
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And if the engine is still on its first run this is something you are going to want to discuss with Cirrus and Continental. They should both want to know the details of your investigations
 
One cylinder is brand new (still on the engine), these 3 are supposed to be fixed or replaced by Friday. Then 8 hours labor to put it all back together.
The plane could be flying again in a week.

The 2 other cylinders are giving no indication of any issues at all. It actually passed annual, we are just doing this as a precaution and appears to have been a good decision.

...and correction, two of these cylinders had issues, but we decided as long as they were removing all the crap to get to them, we might as well pull the 3rd.


Those other 2 will just be assumed fine unless they start talking to me.

@AggieMike88 I can ride shotgun sometime. My schedule is a crapshoot until May 2nd unless I land this other gig. Asked back for a 3rd interview w/ the VP on Friday which seems like a good sign so if that goes well and the numbers work out, I may have a "normal" schedule sooner than that. Consulting is for the birds.
 
GRG55 said:
And if the engine is still on its first run this is something you are going to want to discuss with Cirrus and Continental. They should both want to know the details of your investigations
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It is the original from 2001. Airframe & engine have 1100 hrs.
 
Do you happen to know where on the wrist pin it failed (i.e. middle, just beside the rod, etc)? Just curious.

Regardless, as the others have said, total failure to the point of piston/rod separation (coming from together???) would have been ugly...
 
Omalley1537 said:
Do you happen to know where on the wrist pin it failed (i.e. middle, just beside the rod, etc)? Just curious.

Regardless, as the others have said, total failure to the point of piston/rod separation (coming from together???) would have been ugly...
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No, I don't know yet but I have asked them to keep the part so I can have it as a souvenir.
I will look and upload photos.

I swear I am falling victim to the mentality now of "What's with all these Cirrus engine issues"
I am thinking of switching to gliders.
 
Just a comment: I would have your mechanic file an SDR on the fractured wrist pin and you follow it up by calling the FSDO and chatting with the inspector.That wrist pin should not have failed in 1100 hours. My first thought is a metallurgical failure. Second thought is detonation in addition to thought #1. Continental should be asked to provide some answers. Don't keep the pin as a souvenir, keep it as evidence.

"What's with all these Cirrus engine issues"
On the Cirrus engine issues - these engines are flogged within an inch of their life. Only you can prevent forest fires, umm err wrong sermon - sorry. Only you can prevent your being the next one to pull the big red handle. Back off an inch or two on manifold pressure and let the big bore continental know it is loved. Another tip I learned long, long ago about big bore Continentals (from the factory rep no less as we were discussing various flavors of the IO520) is to let em wind up which drastically lowers cylinder pressure. RPM is not harmful, detonation is. He pointed out that the last RPM mark/line just before the red-line is a black mark - it is black because the factory intends for you to use it.

And I would stop have unquestioning faith in the "ya done good" leaning message. Read Mike Busch on this whole leaning thingy and do some manual testing of your own - methodical and make a graph, etc. Gami has a good article or two on leaning, even if you don't use their product. It ain't black magic.

Synopsis:
Lower cylinder pressures by raising RPM
Lower cylinder pressures by lowering manifold pressure
Stop detonation by backing off a hair on both the throttle and the leaning
Be good to your engine and it will be good to you
Whistle and tap in time to the music as you watch the scenery go by for the full TBO on the fresh cylinders

cheers
denny-o
 
How do I lower manifold pressure? Cirrus didn't give us a blue knob because it would make the planes too expensive
 
btw.....here's a can-o-pee to go with your chute. :D

Urine_sample.jpg
 
SixPapaCharlie said:
No, I don't know yet but I have asked them to keep the part so I can have it as a souvenir.
I will look and upload photos.

I swear I am falling victim to the mentality now of "What's with all these Cirrus engine issues"
I am thinking of switching to gliders.
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Why do that when you can just fly a powered parachute?

Oh, wait, uh...nevermind.
 
There are wrist pins, and there are wrist pin PLUGS. They are different.
 
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SixPapaCharlie said:
How do I lower manifold pressure? Cirrus didn't give us a blue knob because it would make the planes too expensive
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Even if you did have a blue knob, I don't think it would control MP...
 
Whatever you do, put some hours on this engine before you start flying with passengers, make sure it's ok, maybe pull the cowl after first couple of flights and look around, check the bolts are snug, etc
 
Brian I saw your plane at CFDI the other day.
Wesley, Tim and Alexis are great guys . They've done a great job for me! Wouldn't use anyone else.
Hope it works out.
 
Sierra Victor said:
Brian I saw your plane at CFDI the other day.
Wesley, Tim and Alexis are great guys . They've done a great job for me! Wouldn't use anyone else.
Hope it works out.
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Tim is an encyclopedia of airplane knowledge.
I am working with Wes but I bug Tim when I am over there. He has a Grumman Tiger in for annual and he showed me all the ins and outs of that plane.
 
SixPapaCharlie said:
One cylinder is brand new (still on the engine), these 3 are supposed to be fixed or replaced by Friday. Then 8 hours labor to put it all back together.
The plane could be flying again in a week.

The 2 other cylinders are giving no indication of any issues at all. It actually passed annual, we are just doing this as a precaution and appears to have been a good decision.

...and correction, two of these cylinders had issues, but we decided as long as they were removing all the crap to get to them, we might as well pull the 3rd.


Those other 2 will just be assumed fine unless they start talking to me.

@AggieMike88 I can ride shotgun sometime. My schedule is a crapshoot until May 2nd unless I land this other gig. Asked back for a 3rd interview w/ the VP on Friday which seems like a good sign so if that goes well and the numbers work out, I may have a "normal" schedule sooner than that. Consulting is for the birds.
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So it was a good decision to check the three cylinders, it would be another good decision to check the other three cylinders. Wrist pins should not fail. That pin was probably minutes away from putting you and your passengers in a world of hurt on your last flight.

Chances are all the wrist pins in that engine were from the same lot of pins produced. Now it could have been damaged during assembly, 1100 hours ago. Maybe it was dropped, which would bode well for the 5 other pins. Maybe an assembly fixture put a flaw in them, not so good for the others. Maybe something went wrong during manufacturing. It could be a thousand different things that happened, you can't know and that is why I would pull the other cylinders to check those pins. It's not worth the risk in my opinion.
 
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