Aftermarket cylinders

[Marc L.]

Hello everyone. This has probably been answered a million times already but figured I would ask anyways. I have a 65 C with the O360. We found 2 cracks in the case with ECI cylinders. Since we need a new case my partner and I decided to rebuild the engine. We r buying a new case, sending out crank And rods for magnaflux. We know we can not reuse  the ECI cylinders so my question is Millinum Cylinders.  They state cooler temperatures and better fuel/air mixture. We just put a new RAM 520 on a C414 and RAM is using Millinum cylinders. Has anyone here put them on a O360 and if so, what is your experience with them. My co-owner is a A&P and I also work PT at a shop but not an A&P but I do have aviation maintenance in my back ground. 25 years military. We just don’t know anyone with a Mooney with the Millinum Cylinders. 

Edited August 6, 2020 by Marc L.
Grammar

[StevenL757]

With that seemingly extensive amount of work, why wouldn't you consider a factory reman for your "C"?  In general, RAM is a good choice for the T310, 340, 414, and 421 airframes as their RAM engines are all a variant of the TSIO520, but may not be a good fit for the "C".  The two different applications are an apples to oranges comparison.

With a reman and a "0" time logbook for your "C", you know exactly what's in the engine and start everything off on a level playing field.

Steve

[Marc L.]

It’s Kind comes down to $$. We are also removing the gear completely and rebuilding them and also putting on a one piece belly. We Think we can rebuild The engine ourselves cheaper then buying one. We just figured if the Millinum cylinders are what ram are using on their engines and they make them for a O360 if we should try them or not. I know they are two completely different engines just wondering if anyone has used them in a Mooney. Ours is a 1965 M20C. 

Edited August 6, 2020 by Marc L.
Grammar

[pirate]

I had a millennium overhaul with millennium cylinders on my 70C, roughly 500 hours ago.  Very happy with performance and I would do it again. 
 

[Marc L.]

Awesome. Did you see any difference with temps or economy

 

[cferr59]

I have Millenium's on my C.  They were installed a few years ago to replace a set of ECIs and have about 400 hours on them.  They were on when I purchased the airplane so I can't say there are any performance differences, but I haven't had any issues in the 80 hours I have flown it.

[Rjfanjet]

I also have Millenium's on my 68C. They were installed on a top OH before I bought the plane. They were added in 2006. The plane sat a lot til I bought it last year. As of my annual in June, all compressions 78 or 79. Almost 400 hours on the cylinders at this time.

[cctsurf]

I have Milleniums on my 62C with ~600 hours on them.  I can't speak to to difference in temperatures because they were put on before I got the plane.  I have had some warm temperatures, but I blame that on baffling and the installation thereof, not on the cylinders.  I need to go over installation specs on the baffling and make sure mine is installed correctly.

I just borescoped them and the crosshatching is still clearly visible in the walls.  They have always had very high compressions at annual.

In my opinion, the Millenium cylinders are the best ones available at this time.

[Yetti]

9 hours ago, Marc L. said:

It’s Kind comes down to $$. We are also removing the gear completely and rebuilding them and also putting on a one piece belly. We Think we can rebuild The engine ourselves cheaper then buying one. We just figured if the Millinum cylinders are what ram are using on their engines and they make them for a O360 if we should try them or not. I know they are two completely different engines just wondering if anyone has used them in a Mooney. Ours is a 1965 M20C. 

Factory reman is just a bunch of in spec parts assembled.    But you do get the 0 in the log book.   I would rather have a known history of parts.

[carusoam]

Well....

Looks like there is a handful of O360 owners using millennium cylinders...

 

Whenever there is a cylinder problem... somebody will write about it...

The search function is a bit odd... but if you have a particular failure you want to know about.... put it in the search function and see what comes up...

Plenty written about chromed cylinders...cracked cylinders... and even cylinder departures.... lots of valve issues...

Dog house sealing issues... and temperature measuring issues...

 

Take lots of pictures, post the good ones... 

Best regards,

-a-

 

[Marc L.]

Thanks everyone for the reply’s. I will keep everyone updated on the progress. There may actually be another option now. We may have found a complete fuselage with a 50 hour IO360. It’s been stored inside and 100% complete and only sitting a short time. The other owner found corrosion and parted out the AC. It’s complete minus the wings and gear. May fly out to go look at it next week. Of course there would be a complete inspection of the other engine before any decisions are made.