Titan engine problem

[1473C]

Jake,

Did you have a CHT/EGT monitor on that cylinder? Did you see any other signs other than low compressions at annual?

I guess the system worked, you found the problem before it found you!!

No, my cub has no CHT/EGT. Since the last annual I had normal oil temps and pressures. Amazingly, it had great power, started without effort and pinned me to the seat on take off. That is up to last week, the last flight before tear down.
One great aviation lesson out of all this to me is as follows. In my early years, I was assisting with 100 hour inspections on planes that were flown hard every day. Believe it or not, rarely a problem.
This year, I forced myself to do an annual after 25 hours, because after all that is a joke! If I had chosen otherwise, the joke eventually would have been on me. In 45 years I have not seen more torture on a cylinder!
Depending on your CHT/EGT probe location, they might or might not detect a hot intake valve. Usually, the probes are looking at the hot side (exhaust) of the cylinder. I do not have enough experience to know if exhaust gases escaping through an intake valve would reduce EGT. Someone who knows, please comment. Interesting question. Jake

[1473C]

I flew 829CC for two hours at 2400 RPM today in an effort to break in the overhauled cylinder. All seemed to go well.
Since there is little that I could find published on changing a single Carbon Cub cylinder, here is what I learned.
1. My cylinder was overhauled by ProAero in Kamloops B.C. Canada.
2. They were extremely helpful, and tackled the problem immediately.
3. The reconditioned cylinder comes with a piston fitted and in place ready for installation.
4. In order to remove the cylinder and be prepared to reinstall, the following needs to be removed:
A. Intakes of cylinder and opposite cylinder.
B. Exhaust system needs to be pulled down a couple of inches.
C. Oil cooler needs to be unscrewed and rotated up.
D. Plenum needs to be removed. (If you carefully cut the high temp silicone right next to the carbon fabric, the gasket will be basically intact clinging to the engine casting.)
E. The valve cover drains on the cylinder and opposite cylinder need to be removed.
F. The primer line needs to be removed.
G. The plug wires need to be swung out of the way. (Wire ties will have to be cut.)
H The push rods and tubes on the cylinder and opposite cylinder need to be removed to prevent accidental bending during the torque of cylinder base nuts. ( At TDC the plungers will bleed down and the rocker shaft will slide out with finger pressure.)
I. The fore and aft baffles can remain in place because they easily slide fore and aft.
J. The bad cylinder can now be removed.
K. I replaced the lifters and sockets because they had operated without enough push rod clearance.
L. I wanted to inspect my cam lobes carefully but was nervous to turn the crank and rotate an unloaded bearing.
Bobby Looper, who was on the Titan develop team, said not to worry.
M. Once the new cylinder is installed torque both the cylinder and the opposite cylinder.
N. Check the push rod clearance in the new cylinder. ( 0.028-0.080)
O. Put things back together. I could not find an exhaust torque anywhere. Finally, the folks at Cubcrafters found a reference on an assembly drawing. ( 90 in-lbs) Note: Those "no-blows" make it easy to bend an exhaust flange.
P. I put a layer of fresh high temp silicone over the old well preserved.
Q. There are no instructions that I could find for breaking in a single cylinder. So, realizing that idle time was to be avoided, I ran the engine at 1800 RPM for two minutes, uncowled, but with a plenum, pointed into the wind. No leaks. That mimics the engine manual.
R. I then fitted the cowlings and prepared to fly.
S. I ran the engine for two minutes at 1800 RPM during which I did mag and carb ice tests. Then I let go of the brakes and started to roll to takeoff speed. Then I applied full power of about 15 seconds and then reduced to 2400 RPM. That mimics the engine manual.
T. AND NOW I GOT A SURPRISE! The engine ran perfectly for 10/15 seconds, then missed once, then ran, then missed once, then missed twice. I prepared to return and pulled carb heat. It almost would not run. From experience, I pushed the heat in and pulled out the mixture a ways. INSTANT smooth engine.
U. I leaned the engine in the normal way and it continued to run smoothly and would run with carb heat. If I pushed the mixture to full rich and waited for a little while, it would roughen and then instantly smooth out with leaning.
V. I had never taken off this way before. Normally, I apply full power for 30 seconds or so, then reduce to 2100 and immediately lean. Common sense told me not to lean an engine on initial break in for cooling. I was wrong.
These are only highlights. Don't follow this brief outline to do the same thing. Jake
,

[ceslaw]

Thanks for that post. Interesting situation. Glad you got it resolved.

[1473C]

I waited to post this, because I wanted to go through several initial crankings
to be sure.
The starter used to always struggle on one cylinder. Sometimes, it would try and fail. Other times, it would hesitate and finally go.
Now, it just cranks at equal speed. Learn by doing. Jake

[Daveembry]

I waited to post this, because I wanted to go through several initial crankings
to be sure.
The starter used to always struggle on one cylinder. Sometimes, it would try and fail. Other times, it would hesitate and finally go.
Now, it just cranks at equal sped. Learn by doing. Jake

Jake. How was this handled by Titan/CC? Was it considered warranty or did you have to pay for it?

[1473C]

With 450 hours on the engine, I did not expect either Cubcrafters or Continental to offer warranty coverage. IMO the fact that the cylinder lasted 450 hours without sufficient bleed down time is a plus. Shows how tough the design is!
Continental, Cubcrafters and ProAero all helped me dig out information. Bobby Looper, at Continental, knows that engine from the drawing board forward. Interestingly, he used to be a Beaver pilot. Jake

[seastar]

You are very lucky it was only one cylinder.
I had all four of mine replaced at 250 hours.
Titan gave me new cylinders and I paid the labor.
The new cylinders are showing modest distress with about 30 hours on them.
one runs so hot I must run full rich at 2100 RPM to keep the CHT under 400 F while another runs cold.
I don't trust the Titan engine and wish there were an alternative.
I may get rid of the airplane because it has more down time than fly time now.
The airplane has been very unreliable since new.
Some things have broken more than once and it looks like the cylinders may be next on the list.
Watch that new cylinder till it has 100 or more hours.
Bill

[ncshp]

What is or is there any difference in the Titan 340CC and the OX-340CC. Is it cylinders internal parts or just labeling?

[seastar]

I have never heard of an OX-340

[Eddie Stash]

I have also had the #4 cylinder fail with a burned intake. Since the failure i got van engine management system. Seems you can not run the light speed ignition engine the same way as a magneto fired. The light
speed ignition will fire a very lean mixture. So leaning till rough then slightly enriching is running very lean. Also the carb nozzle should be drilled out to a #28 drill bit .1370".