RoundTwo Posted February 4 Report Posted February 4 I’m attempting to re-ring a set of CermiNil nickel cylinders to get me 400-500 hours closer to overhaul without going for a full top OH because it looks like my only other option is four new Lycoming cylinders for about $12,000 in parts. I could also continue to run the old rings and just carry more oil with me. I’ll be attempting to get a ring finish on the jugs, but can’t find any information on which rings would be best. I know this isn’t the best plan, but I’m trying to find the most palatable compromise to avoid large expense and a six month downtime for an OH. Thanks, Chuck Quote
mike_elliott Posted February 4 Report Posted February 4 The rings are the sacrificial wear item, I would just go with std steel rings. Quote
RoundTwo Posted February 4 Author Report Posted February 4 1 minute ago, mike_elliott said: The rings are the sacrificial wear item, I would just go with std steel rings. That is my gut reaction but wanted to reach out to the hive mind because I have found references from 2010 speaking about using plasma coated rings. I haven’t ever heard of plasma coated rings and wonder if they went away like these CermiNil cylinders did. Chuck Quote
A64Pilot Posted February 4 Report Posted February 4 Can you have those Honed? If not then you might be better off letting sleeping dogs lie. Between Chrome, Cermichrome and CermiNil I get confused Quote
kortopates Posted February 4 Report Posted February 4 Call J&J Airparts in TX, they can often hone Nickel and if so re-ring it. They’re not real fast though.Sent from my iPhone using Tapatalk 1 Quote
RoundTwo Posted February 4 Author Report Posted February 4 1 hour ago, A64Pilot said: Can you have those Honed? If not then you might be better off letting sleeping dogs lie. Between Chrome, Cermichrome and CermiNil I get confused Everything I’ve run across says it’s a one shot deal. I’ve spoken to Gibson and he referred to them as disposable. Yes, running these until performance takes a hit is a definite possibility. As far as those cylinders go, they’re all done and gone now. None of them turned out to be the silver bullet they were hoped to be. Quote
A64Pilot Posted February 4 Report Posted February 4 IF I understand and I certainly may not, but what happens is they wear smooth and don’t hold an oil film anymore, once that happens wear is rapid, just like bore glazing and or bore polishing. If you go through all the work to pull them and spend $$ on rings without being able to hone them, well the rings aren’t going to seat and it’s at least possible that your oil consumption could increase substantially. Having said that I book marked these from someone else who posted them on another thread, they are to be installed and torqued as a cylinder is removed, this maintains the torque the pulls the two case halves together. My plan before I saw this was to find four bad cylinders and use a band saw to cut off the bases, but at this price DIY just doesn’t make sense. https://flyboyaccessories.com/products/cylinder-torque-plate-for-lycoming-engines Quote
jetdriven Posted February 4 Report Posted February 4 I think the newest thing here is they run the 80 grit hone through the cylinder and then a 400 grit hone, both the bottle brush style. . And then plain iron rings, the kind used for chrome cylinders. But probably the valve guides are worn out at this point as well so you probably want to go ahead and have those looked at my guy. Tim is a wizard with cylinders. We took the parrot wizard’s plane from a QT every three hours to a QT every 25 probably. Quote
takair Posted February 4 Report Posted February 4 I’m going to follow this closely. I have 4 otherwise healthy cylinders on my shelf. I pulled them at about 1000TSMOH because the plasma faced rings started to delaminate and oil burn was going up. I never sorted out which rings were acceptable and which process for honing was acceptable. Unfortunately, I missed the warranty period by many years, apparently mine didn’t show major symptoms in a timely manner. If you are not aware, ECI had SI 06-6 regarding the rings and vaguely the required action. They used to have a kit to rejuvenate the cylinders and had replacement rings. There is also SI 96-4. It suggests that the plasma faced rings are “top compression position only. Cast iron rings below”. SI92-9-6 talks about diamond honing the cylinders. They call out ECI part numbers for the oils and such, but I suspect much of it can be reverse engineered. My local shop was willing to give it a try but warned that the honing is difficult to do well and sometimes leads needing to replace the jug anyway. I suspect he wouldn’t even offer anymore. In the end, between his reluctance to hone and my inability to sort out which rings, I ended up buying new-surplus jugs and new PMA pistons and rings. Would still love to make these into a spare set of serviceable jugs. Quote
RoundTwo Posted February 4 Author Report Posted February 4 45 minutes ago, jetdriven said: I think the newest thing here is they run the 80 grit hone through the cylinder and then a 400 grit hone, both the bottle brush style. . And then plain iron rings, the kind used for chrome cylinders. But probably the valve guides are worn out at this point as well so you probably want to go ahead and have those looked at my guy. Tim is a wizard with cylinders. We took the parrot wizard’s plane from a QT every three hours to a QT every 25 probably. I’ll contact Tim. Another trick I’ve been told is to cover the stones on a hone with emery cloth and that will cut them enough to allow a ring finish. The original crosshatch is still there, so all it should need is some roughness to seat new rings. HOPEFULLY Quote
takair Posted February 4 Report Posted February 4 Reading SI 06-6, it seems like the ring kits are ST203 and CN203. Quick Google search seems to hint that they may be procurable. I don’t know why I gave up on that…. Please keep us posted on your findings. Quote
mike_elliott Posted February 4 Report Posted February 4 Your close enough, just run the cyl up the road to 9a5 and let Carlus Gann prep it. 1 Quote
RoundTwo Posted February 4 Author Report Posted February 4 7 minutes ago, mike_elliott said: Your close enough, just run the cyl up the road to 9a5 and let Carlus Gann prep it. I took this one up to him on Friday to look at. Wow! What an awesome shop! He’s the one who told me about using emery cloth. I didn’t ask him about the work knowing he’s 6 months out for overhauls. I’ll call him in the morning and see if he could work them in when I get rings. Quote
RoundTwo Posted February 5 Author Report Posted February 5 22 minutes ago, takair said: Reading SI 06-6, it seems like the ring kits are ST203 and CN203. Quick Google search seems to hint that they may be procurable. I don’t know why I gave up on that…. Please keep us posted on your findings. Thanks for the document findings. These will be helpful sorting things out. Quote
A64Pilot Posted February 5 Report Posted February 5 27 minutes ago, RoundTwo said: I took this one up to him on Friday to look at. Wow! What an awesome shop! He’s the one who told me about using emery cloth. I didn’t ask him about the work knowing he’s 6 months out for overhauls. I’ll call him in the morning and see if he could work them in when I get rings. I have one of his performance engines, in my opinion they are worth the cost, it was a big deciding factor in me buying the airplane. I’ve never been to his shop, but it’s my understanding that he has someone that does cylinders as in hones valve guides, 7 angle valve jobs and ports and polishes them. I think, maybe this person has some NASCAR head experience, but maybe I dreamed that who knows. I’d trust Carlos’s word if he says he can make it work I’d bet lunch he can. If your expecting an overhaul sometime in the future I think I’d ask if I could schedule one by giving a deposit, can’t hurt to ask. Quote
RoundTwo Posted February 5 Author Report Posted February 5 8 minutes ago, A64Pilot said: I have one of his performance engines, in my opinion they are worth the cost, it was a big deciding factor in me buying the airplane. I’ve never been to his shop, but it’s my understanding that he has someone that does cylinders as in hones valve guides, 7 angle valve jobs and ports and polishes them. I think, maybe this person has some NASCAR head experience, but maybe I dreamed that who knows. I’d trust Carlos’s word if he says he can make it work I’d bet lunch he can. If your expecting an overhaul sometime in the future I think I’d ask if I could schedule one by giving a deposit, can’t hurt to ask. It’s a race engine shop for sure. There are Hendrick’s boxes everywhere. Quote
GeeBee Posted February 5 Report Posted February 5 Carlus used to be Bill Elliott's engine guru. Quote
mike_elliott Posted February 5 Report Posted February 5 10 hours ago, GeeBee said: Carlus used to be Bill Elliott's engine guru. naw, that was Ernie, but Carlus was like fam to them and did all of Bills piston plane engines. Carlus told me their secret why their straight away handling was so much better than everyone the years they dominated 1 Quote
A64Pilot Posted February 5 Report Posted February 5 I had heard of the NASCAR connection, and while I’m an open wheel road racing fan myself and don’t follow NASCAR, back in the day when I was building drag bikes we had two brothers that did NASCAR heads come down in off season and help us, it’s where I learned about what little I know about heads from them, so I quickly formed the opinion that while I didn’t like NASCAR, they sure had heads down to a science, and this was 1980 before it got the popularity it has now. Most of the power we made came from the head. A lot of port shaping isn’t logical, by that I mean what works is sometimes not what you think would and the flow bench that should tell you everything doesn’t. What flows good on the bench may not on the bike, once you think about it there are many things a bench can’t do, heat, velocity and pulses to name a few. Polishing is easy, porting on the other hand is an art, it’s not intuitive. Quote
RoundTwo Posted February 5 Author Report Posted February 5 1 hour ago, mike_elliott said: naw, that was Ernie, but Carlus was like fam to them and did all of Bills piston plane engines. Carlus told me their secret why their straight away handling was so much better than everyone the years they dominated It’s not nice to tease people. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.