Cylinder overhaul recommendations
 

Hello VAF...

Looking for recommendations on cylinder shops.

In my recent thread I was having an issue with run away CHT on number 2. I thought it was resolved, but was sadly mistaken. After checking everything else the last thing to do was to remove the cylinder. What we found was that the cylinder is pushing oil. The face is valve is blackened with burnt oil and so is the top of the piston. We expected to find an obvious reason for why this was happening, ie...a broken ring, but did not.

The heat is coming from the burnt oil deposits which are turning red hot. On my last flight everything was fine until again the number 2 CHT rapidly started increasing....and continued increasing to 450 after I pulled power to near idle.

So now I will be calling around to some cylinder shops and check out my options for overhauling this cylinder. Figuring on at least a new piston and rings. I have chrome cylinders...not sure how the new rings would seat without honing. Can the chrome cylinders be rechromed?... what about NuChrome...?

OH Cost vs new..these are angle valve cylinders too..

I have used Don George in Orlando may times. His shop does good work and the cost is very reasonable. The turn times and communication during the repair evolution is great as well.

An angle valve cylinder will almost always be cheaper to overhaul than to replace with new. A parallel valve cylinder usually costs 60%-80% of the new cost to overhaul.

+1 For Don George
 

Has done many for the folks in this neighborhood --- did an engine for me, way back. Good reputation.

AES
 

Tina, the Cylinder Lady, at AES in Chandler, AZ has done good work for local experimental builders.

http://www.aircraftenginespecialists.com/cylinder.html

AES recently assembled my O-360-A1A from my yellow tagged parts and will test run it as soon as I have the cowling finished.

Cyl ovhl
 

Brown cylinder, Tulsa Oklahoma Larry brown owner, I would cross the pacific on his cylinder work

Just a thought, read up on this. Particularly Mike Busch on cylinders.
www.avweb.com/news/maint/182902-1.html
They seem to have a lifespan. Why not go new for a little more and, hopefully, not have to go through this again in your lifespan? Aluminum isn't like steel and only had so many cycles in them before they croak. Kinda like ski bumps, you only have so many in your knees then poweee!
I bought a plane with first run overhauls, they lasted 700 hours - whoopee. Had they been new and gone 2000 hrs or more I'd never have overhauled my engine for $17,000 and been down for 9 months.
But I have several friends building engines for their under construction RVs with used cylinders and wonder what the heck they are thinking. Just my 2 cents...
ps: ask these "good results" pozters about longetivity...note they don't include that in their posts....

I have to agree with new over overhaul. The overhauled cylinder I put on my O-320 lasted only 200 hours before it was replaced by new. Anecdotal, but after that experience I will go new the next time I need to replace a cylinder.

I had a very good result with Poplar Grove Airmotive.

Dan

here is a longevity report for you, I have run overhauls in a rental fleet for years and had very long life from them. infrequent use kills engines.

yes they have a life, its a whole lot longer than two or three rebuild cycles. most failures are do to parts that are replace in a overhaul. the biggest problem i have seen in bad valve seats which all get replaced. also a lot of guide problems, which also get replaced.

A good overhaul shop does a lot better job of setting up a cyl than the factory.

I don't buy into the new is better idea, quality work is better.

bob burns
RV-4 N82RB

That there is truth. A cylinder isn't good because its new. Its good because its good. The best Bell47 operator I know sends all his NEW cylinders out for rework. He's been living in front of an O435 since vietnam and does NOT crash.