What would you do?

[Tom-D]

even if all's I need is new guides and seats on a 300 hr cylinder?

If you only got 300 hours of run time from a cylinder, wasn't the cylinder crap to start?

I've never had unhappy customers with new cylinders, I have had with used overhauled cylinders.

 

[FORANE]

I got about 280 hours out of my overhauled cylinder before I replaced it with new. Next ones I buy will be new. A bargain isn't really a bargain if you have to pull and replace it after a short run.

 

[timwinters]

The engine, including cylinders, in my plane are all original best anyone can tell. The case definitely is, I confirmed with Continental that it was sold to Cessna in '58 and there's no mention of the cylinders ever being replaced, only OH'ed. They're currently on their third run and at at 3350ish hours total time.

I think it's uber cool having the all original power plant. Kinda like having a '57 Chevy with all matching numbers.

My cylinder guy says they definitely have one more run left. It'll just depend what kind of a mood I'm in when it's OHed next. I'll likely go new but it'll be sad to loose the nostalgia of all original.

 

[EdFred]

So this is what the cylinders looked like. I don't know which pictures are from which cylinder. The "pitting" must be junk on the camera lens as the pattern is the same in all three pictures.

I've run this by some (non-av) engine guys, and they are stumped as well.

End gaps on the rings: Correct amount.
Gap between cylinder and piston: Dead in the middle of tolerance.
Rings: Correct rings - SL5401-SC

After pulling the cylinder (which now sits at the cylinder shop with the rings and piston for their inspection) there was Silicon Carbide found in the groove. I'm not sure whether that should or shouldn't happen. Some of the groove are deep enough to get a fingernail in.

Edit: Supposedly correct rings. Depending on the piston PN, there are two different ring sets. It's possible the cylinder shop sent FW rings instead of HW rings.

 

[Henning]

Holy crap, was this assembled in a sand box? Didn't you guys take them apart, clean, and inspect them before putting them on?

 

[jesse]

Holy crap, was this assembled in a sand box? Didn't you guys take them apart, clean, and inspect them before putting them on?

I've observed many A&Ps just take them out of the box from the overhaul shop and bolt them up.

I can't really determine how this could have happened other then something was in the cylinders that shouldn't have been. How it got in there..is the question?

Not sure...Any chance the engine is making metal that is getting into the cylinders? I'm just taking wild ass guesses.

 

[EdFred]

Holy crap, was this assembled in a sand box? Didn't you guys take them apart, clean, and inspect them before putting them on?

We did all of that. Pistons came off the connecting rods got cleaned, removed all carbon, etc... cylinders were sent to the shop, and came back looking great. Everything was checked before assembly, I even saw everything before it went back together.

 

[EdFred]

I've observed many A&Ps just take them out of the box from the overhaul shop and bolt them up.

I can't really determine how this could have happened other then something was in the cylinders that shouldn't have been. How it got in there..is the question?

Not sure...Any chance the engine is making metal that is getting into the cylinders? I'm just taking wild ass guesses.

No metal in the filter, and if the engine was making metal, why would it have showed up in the redone cylinders, and not the replaced cylinder? The cylinder shop claims that the grooves was caused by carbon. And it magically happened on all 5 cylinders simultaneously. Sorry, not buying that.

I'm leaning towards a piston/ring mismatch. In the O-540-A there are 2 different pistons that can go in the chrome cylinders. One with half wedge rings, and the other with full wedge rings. The cylinder shop gave us half wedge rings. Verifying which pistons I actually have.

And we pulled one off them a second time, had it re-chromed, and this happened again within 20 hours.

 

[Henning]

We did all of that. Pistons came off the connecting rods got cleaned, removed all carbon, etc... cylinders were sent to the shop, and came back looking great. Everything was checked before assembly, I even saw everything before it went back together.

WTF then, somehow you took in a load of crap into your induction, maybe a load of grit got blown into a hose or something. This looks like contamination damage.

What does the oil and filter look like?

 

[EdFred]

WTF then, somehow you took in a load of crap into your induction, maybe a load of grit got blown into a hose or something. This looks like contamination damage.

What does the oil and filter look like?

Absolutely nothing found in the filter. If this was an induction issue (I never use carb heat) then why is it only affecting the 5 chromed cylinders that went to the shop, and not the 6th nitrided cylinder. Also, one of the 5 was pulled the next year, redone, and it's back in the same condition as the other 4.

This is why we are stumped. If something got sucked into the system, it should present itself in all 6 cylinders. And after pulling one and re-doing it, all that crap should have been gone, but it's got the same pattern.

 

[Henning]

Absolutely nothing found in the filter. If this was an induction issue (I never use carb heat) then why is it only affecting the 5 chromed cylinders that went to the shop, and not the 6th nitrided cylinder. Also, one of the 5 was pulled the next year, redone, and it's back in the same condition as the other 4.

This is why we are stumped. If something got sucked into the system, it should present itself in all 6 cylinders. And after pulling one and re-doing it, all that crap should have been gone, but it's got the same pattern.

Then it's a junk chrome job, throw them away, get 5 more new ones to match #6. I wouldn't keep chasing with these jugs or shop. A soft iron ring shouldn't do that to a chromed cylinder.

 

[Chip Sylverne]

That vertical scoring looks exactly like what happens when you overheat a 2 cycle motorcycle engine, or forget to add oil to the gas.

Which says to me, lack of lubrication.

 

[N801BH]

Absolutely nothing found in the filter. If this was an induction issue (I never use carb heat) then why is it only affecting the 5 chromed cylinders that went to the shop, and not the 6th nitrided cylinder. Also, one of the 5 was pulled the next year, redone, and it's back in the same condition as the other 4.

This is why we are stumped. If something got sucked into the system, it should present itself in all 6 cylinders. And after pulling one and re-doing it, all that crap should have been gone, but it's got the same pattern.

I still contend it is Chrome rings used in Chrome cylinders... It shows the classic "tearing" of the chrome surface.... IMHO...

 

[Henning]

I still contend it is Chrome rings used in Chrome cylinders... It shows the classic "tearing" of the chrome surface.... IMHO...

Who would put chrome rings in a chrome bore?

 

[N801BH]

Who would put chrome rings in a chrome bore?

It has been done before..........

And it will be done again....

 

[EdFred]

The rings are NOT chrome. That has bee quadruple verified by part number and visual inspection.

I doubt it's not enough oil since the temps would have been way way higher than what they were on break in. Other than the one that was sent back a second time, they never got above 320 or 330 and then dropped back to 300 immediately.

 

[EdFred]

Then it's a junk chrome job, throw them away, get 5 more new ones to match #6. I wouldn't keep chasing with these jugs or shop. A soft iron ring shouldn't do that to a chromed cylinder.

Sure just send me 7500 bucks.

 

[docmirror]

Back to a process issue with the jugs/rings. Where they all sourced from the same place? Went through the same prep process? All rings from the same place? All pistons too? Other jugs from that source coming back funky? I don't think this is ingested from outside the bores. This is making the grooves right in the jug itself. Maybe bits off the valve guide, but that's a big stretch. Agreed that it looks like heat expansion, or incorrect tempering of some of the metal. Get some pics of the piston crowns, and rings if you can.

 

[Chip Sylverne]

Did they file the rings to get the proper gap, and forget to properly deburr them, and get some crap in the lands? Shy on lube during assembly?

 

[N801BH]

The rings are NOT chrome. That has bee quadruple verified by part number and visual inspection.

I doubt it's not enough oil since the temps would have been way way higher than what they were on break in. Other than the one that was sent back a second time, they never got above 320 or 330 and then dropped back to 300 immediately.

I should have been a bit clearer......

You need to run soft rings against hard cylinder walls , and vis-a -versa... Soft walls against hard rings.....

Piston rings have come a LONG way in 50 years... From the softest to the hardest...

Cast Iron...
Steel....
Moly....
Moly , Moly....
Plasma coated....
Chrome...
Hard Chrome......

There is NO doubt in my mind the wrong hardness ring was run against wrong type of cylinder wall...... ..

Or,,, the only far fetched reason I can think of is it was assembled with NO oil on the surfaces and the rings galled during the first start....

No one could be that dumb...

 

[Skip Miller]

Sucks to have that kind of OCD, well, you ****ed yourself. Now you get to replace them with new ones to match the other. You might also send them off to a better shop like Charlie Merlot's




and have him fix them if he can.

-Skip

 

[Henning]

The rings are NOT chrome. That has bee quadruple verified by part number and visual inspection.

I doubt it's not enough oil since the temps would have been way way higher than what they were on break in. Other than the one that was sent back a second time, they never got above 320 or 330 and then dropped back to 300 immediately.

Just a real quick check, why don't you break a ring and make sure it is what the part number says it is. It would not be the first event of mis-packaged parts that ever occured.

 

[N801BH]

Just a real quick check, why don't you break a ring and make sure it is what the part number says it is. It would not be the first event of mis-packaged parts that ever occured.

I will suggest one better..... Show us some pics of the rings.... We have seen pics of every thing else...

 

[EdFred]

Short staffed at work this week and next, so I can't get out to the airport while my A&P is there for any pictures.

 

[nrpetersen]

Are the three pictures of the bores above showing pits in the chrome? or what are they? Could pieces of chrome be spalling off the bores? Never seen that before though.

 

[N801BH]

Are the three pictures of the bores above showing pits in the chrome? or what are they? Could pieces of chrome be spalling off the bores? Never seen that before though.

Just run Chrome rings in a Chrome bore.......

It will do it EVERY time...

 

[EdFred]

The "pitting" must beis definitely junk on the camera lens as the pattern is the same in all three pictures.

Are the three pictures of the bores above showing pits in the chrome? or what are they? Could pieces of chrome be spalling off the bores? Never seen that before though.

I already addressed that. Open up the picture and click next/prev and you will see the "pits" never move.

We also verified, again, the rings are what they were labeled as. The rings are the correct rings for the pistons and the cylinders.

I also verified that:
It was not re-assembled in a sand box.
The grooves were cleaned out.
The cylinders were lubed properly for installation.
The temps were well within/under normal range when it was first started and broke in.
Nothing was found in the filter after either oil change. (we're going to run an analysis just to see if anything is in there, but I know that's going to come up empty since #6 is perfect, and nothing was in the filter(s).

At this point I think I am just going to have them rehoned and relined by a different shop, and put in new pistons and rings. If it looks like it should after a few hours, I'm going to request the first shop refund my money, and if they don't, there will be a huge DO NOT USE ___________ email blast sent out, and a thread started on here and the red board, along with a filing for damages in court. It will be pretty easy to convince 12 people that the first shop screwed up. We will just play the scary little airplane could fall out of the sky and into your house card.

If the scoring returns, I will be checking into the ER with a coronary.

And Ben, they are not chrome rings. They are the rings that Lycoming says to use, and that has been verified by my A&P and the cylinder shop.

 

[N801BH]

I already addressed that.

We also verified, again, the rings are what they were labeled as. The rings are the correct rings for the pistons and the cylinders.

I also verified that:
It was not re-assembled in a sand box.
The grooves were cleaned out.
The cylinders were lubed properly for installation.
The temps were well within/under normal range when it was first started and broke in.
Nothing was found in the filter after either oil change. (we're going to run an analysis just to see if anything is in there, but I know that's going to come up empty since #6 is perfect, and nothing was in the filter(s).

At this point I think I am just going to have them rehoned and relined by a different shop, and put in new pistons and rings. If it looks like it should after a few hours, I'm going to request the first shop refund my money, and if they don't, there will be a huge DO NOT USE ___________ email blast sent out, and a thread started on here and the red board, along with a filing for damages in court. It will be pretty easy to convince 12 people that the first shop screwed up. We will just play the scary little airplane could fall out of the sky and into your house card.

If the scoring returns, I will be checking into the ER with a coronary.

What the hell does that mean ????

 

[EdFred]

What the hell does that mean ????

rechromed.

 

[Henning]

I already addressed that. Open up the picture and click next/prev and you will see the "pits" never move.

We also verified, again, the rings are what they were labeled as. The rings are the correct rings for the pistons and the cylinders.

I also verified that:
It was not re-assembled in a sand box.
The grooves were cleaned out.
The cylinders were lubed properly for installation.
The temps were well within/under normal range when it was first started and broke in.
Nothing was found in the filter after either oil change. (we're going to run an analysis just to see if anything is in there, but I know that's going to come up empty since #6 is perfect, and nothing was in the filter(s).

At this point I think I am just going to have them rehoned and relined by a different shop, and put in new pistons and rings. If it looks like it should after a few hours, I'm going to request the first shop refund my money, and if they don't, there will be a huge DO NOT USE ___________ email blast sent out, and a thread started on here and the red board, along with a filing for damages in court. It will be pretty easy to convince 12 people that the first shop screwed up. We will just play the scary little airplane could fall out of the sky and into your house card.

If the scoring returns, I will be checking into the ER with a coronary.

And Ben, they are not chrome rings. They are the rings that Lycoming says to use, and that has been verified by my A&P and the cylinder shop.

You'll be throwing away money and time, get some fresh steel bores and start over, recover what you can from the guy who screwed up your cylinders, they've basically been junked. You fixed something that wasn't broke and screwed yourself, quit digging the hole and climb out of it.

 

[cirrusmx]

You'll be throwing away money and time, get some fresh steel bores and start over, recover what you can from the guy who screwed up your cylinders, they've basically been junked. You fixed something that wasn't broke and screwed yourself, quit digging the hole and climb out of it.

what was the total cost? for anything less than several grand i would probably write the screw up as a learning experience and move on.

 

[N801BH]

You'll be throwing away money and time, get some fresh steel bores and start over, recover what you can from the guy who screwed up your cylinders, they've basically been junked. You fixed something that wasn't broke and screwed yourself, quit digging the hole and climb out of it.

Agreed 100%.......

Cut your losses and move on....

 

[EdFred]

You'll be throwing away money and time, get some fresh steel bores and start over, recover what you can from the guy who screwed up your cylinders, they've basically been junked. You fixed something that wasn't broke and screwed yourself, quit digging the hole and climb out of it.

3 cylinders had issues on the original deal. Things WERE 'broke'

Looks like I'm shelling out another 5 grand plus labor on this deal.

 

[Henning]

3 cylinders had issues on the original deal. Things WERE 'broke'

Looks like I'm shelling out another 5 grand plus labor on this deal.

Yep, then you should have replaced the broke ones and left the others alone, or just topped with all new to begin with, chroming is a bad deal especially up by the Acme threads. Airplanes ain't cheap to keep.

 

[Clark1961]

Yep, then you should have replaced the broke ones and left the others alone, or just topped with all new to begin with, chroming is a bad deal especially up by the Acme threads. Airplanes ain't cheap to keep.

chroming is okay but ya gotta lay nickel under it, most folks don't know/do that

 

[Henning]

chroming is okay but ya gotta lay nickel under it, most folks don't know/do that

It's not okay really because of the boring process thining the structure at the Acme threads holding the head on. Chrome cylinders are notorious for cracking there.

 

[Clark1961]

It's not okay really because of the boring process thining the structure at the Acme threads holding the head on. Chrome cylinders are notorious for cracking there.

i\If removal of a couple thousandths lead to cracking the problem is not material removal, there has to be stress risers introduced.

 

[Henning]

i\If removal of a couple thousandths lead to cracking the problem is not material removal, there has to be stress risers introduced.

Whatever, but I know I have seen it far more often with orange barrels than plain.

 

[Clark1961]

Whatever, but I know I have seen it far more often with orange barrels than plain.

That observation makes me think there was pitting underneath the chrome or hydrogen invasion.

What we learned offshore was that chrome didn't work without nickle underneath.

Not a lot of folks pay detailed attention to metallurgy...it might help in these situations...

 

[Henning]

That observation makes me think there was pitting underneath the chrome or hydrogen invasion.

What we learned offshore was that chrome didn't work without nickle underneath.

Not a lot of folks pay detailed attention to metallurgy...it might help in these situations...

The fact that i can't personally assure the process, and record of failure and increased oil consumption, leads me to avoid chrome cylinders.