Valve guide replace

Silvaire

Silvaire

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Silvaire
I've got a cylinder off my Continental C90 that needs a new exhaust valve guide. Nothing else wrong with it. Used to be you could find someone to do this but seems like not nowadays. It's as if a culture has developed where you don't fix things anymore, if it's got a scratch just replace the whole darn thing with a new one. sigh

Well anyway I'm in the SF Bay area so if anyone knows of someone who can replace a guide, or even knurl it, I'd appreciate a tip.
 
(Wrong side of the country for you, but...) A few years ago I had a burnt exhaust valve in one cylinder. Sent it to Columbia Aircraft at N13 (they offered the fastest turnaround of all places I called), they repaired it and sent it back (with new rings and such) for 1.2 AMU.

My IA considered doing the rope trick to drop/lap the valve and clean the guide, but at the cost quoted for the engine shop to repair it he said it would be better/more cost-effective long-term to pull the jug and send it out.
 
AV8R_87 said:
(Wrong side of the country for you, but...) A few years ago I had a burnt exhaust valve in one cylinder. Sent it to Columbia Aircraft at N13 (they offered the fastest turnaround of all places I called), they repaired it and sent it back (with new rings and such) for 1.2 AMU.

My IA considered doing the rope trick to drop/lap the valve and clean the guide, but at the cost quoted for the engine shop to repair it he said it would be better/more cost-effective long-term to pull the jug and send it out.
Click to expand...
“…the rope trick to drop/lap the valve and clean the guide…” ??
 
AV8R_87 said:
(Wrong side of the country for you, but...) A few years ago I had a burnt exhaust valve in one cylinder. Sent it to Columbia Aircraft at N13 (they offered the fastest turnaround of all places I called), they repaired it and sent it back (with new rings and such) for 1.2 AMU.

My IA considered doing the rope trick to drop/lap the valve and clean the guide, but at the cost quoted for the engine shop to repair it he said it would be better/more cost-effective long-term to pull the jug and send it out.
Click to expand...

When a brand new cylinder can be had for 1.3 AMUs, 1.2 for a repair doesn’t seem like much of a bargain.

www.aircraftspruce.com

Superior Millennium Cylinder SA10200-A20P With Valves | Aircraft Spruce ®

Superior Millennium Cylinder SA10200-A20P With Valves Through hardened steel barrel - uniform hardness all the way through the steel walls allowing the barrel to provide even wear while withstanding extreme cylinder temperatures and pressur
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My understanding has been that you have to heat the head in order to

install the guide. The whole process may produce some distortion and

necessitates of the valve seats. Assure it goes to someone with the

proper equipment for the task.
 
Half Fast said:
When a brand new cylinder can be had for 1.3 AMUs, 1.2 for a repair doesn’t seem like much of a bargain.

www.aircraftspruce.com

Superior Millennium Cylinder SA10200-A20P With Valves | Aircraft Spruce ®

Superior Millennium Cylinder SA10200-A20P With Valves Through hardened steel barrel - uniform hardness all the way through the steel walls allowing the barrel to provide even wear while withstanding extreme cylinder temperatures and pressur
www.aircraftspruce.com www.aircraftspruce.com
Click to expand...
You're looking at an O-200 cylinder. I have an O-320 (more lile $1650 new), and that happened when we had that little thing called "supply chain disruption", and oil filters had a 6 month lead time and cost double what they do now. I think the wait time for a new cylinder was over a year.
 
Carefully remove the piston, get the guide replaced, and reinstall the piston. No honing or new rings required. Any local aircraft engine shop should be able to help you. I’ve done it this way a few times. All good.
 
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AV8R_87 said:
You're looking at an O-200 cylinder. I have an O-320 (more lile $1650 new), and that happened when we had that little thing called "supply chain disruption", and oil filters had a 6 month lead time and cost double what they do now. I think the wait time for a new cylinder was over a year.
Click to expand...

Understood. These days, though, the cost of repairs often approaches the replacement cost. When I did my OH last year, three of the cylinders needed repair, and the repair on each was within about $300 of the replacement cost. To me, it was worth it to just install all brand new cylinders, and new Superiors for my O360 were in stock.
 
A nd
Half Fast said:
Understood. These days, though, the cost of repairs often approaches the replacement cost. When I did my OH last year, three of the cylinders needed repair, and the repair on each was within about $300 of the replacement cost. To me, it was worth it to just install all brand new cylinders, and new Superiors for my O360 were in stoc
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And hope no ADs come out on those brand new cylinders. I have a set of first run cylinders. I will seriously consider having them OH when the time come versus purchasing a new set.
 
aren't they just press out/in? maybe ream? thats like $100 worth of parts if you buy everything new.

A valve seat it a little more complicated but not beyond the reach of hand tools and elbow grease.
 
AV8R_87 said:
(Wrong side of the country for you, but...) A few years ago I had a burnt exhaust valve in one cylinder. Sent it to Columbia Aircraft at N13 (they offered the fastest turnaround of all places I called), they repaired it and sent it back (with new rings and such) for 1.2 AMU.

My IA considered doing the rope trick to drop/lap the valve and clean the guide, but at the cost quoted for the engine shop to repair it he said it would be better/more cost-effective long-term to pull the jug and send it out.
Click to expand...
One condition is sticking valve due to carbon and lead. Another condition is a worn out guide. Part of the rope trick is a wobble test that indicates if the guide is good.Why one would remove a cylinder and replace a guide when cleaning the would cure the issues is a bit baffling.
 
Sal’s Cylinders near DFW will refurb for about $400 with return shipping.
 
Well after some asking around I found a shop that will do it. Not exactly local but close enough that I could conceivably drive down there and drop it off (3hrs) Too bad I don't have TWO airplanes, then I could just fly it down there :cool: but it's in Visalia so I could at least take the scenic route back through Sequoia National Park and make a nice day trip out of it. I'll box it up anyway, get a shipping quote and decide what I want to do.

Thanks for all the replies
 
Half Fast said:
Got any friends with airplanes?
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Maybe back in the days but I'm 72 so I have no old buds champing at the bit to fly me down the valley and log a couple of hours nor would I want to be the type of "friend" who cold calls you for the first time in a year asking for a favor. Nope, the best solution for me is to get a second airplane, preferably a fast one d;-)
 
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