Page 1 of 2 12 LastLast
Results 1 to 10 of 20

Thread: Titan engine problem

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1
    Member
    Join Date
    Dec 2012
    Location
    Sangerville Maine
    Posts
    39

    Default Titan engine problem

    When I started on my annual inspection this week, I found a weak cylinder. 30 hours ago #4 measured 70/80 but this week was more like 30/80. The other 3 were good and unchanged over 30 hours. I ran the plane on the ground again and remeasured. No miraculous recovery. I then flew above my field for 45 minutes, and that didn't help either.
    The rush of air escaping the cylinder appears loudest from the carb. The engine has 450 hours.
    On a lark, I called Continental to pick someone's brain as to why a cylinder would wilt so suddenly and be leaking from an intake, in my opinion unusual. They put me through to Bobby Looper who worked on the development of the Titan. To say the least, he was helpful and informed. Immediately, he said, "pull all four valve covers and measure the push rod clearances".
    When I did that the three good cylinders are all within spec. (0.028/0.080). #4 is very tight on both intake and exhaust, maybe 0.012. Also, it takes quite a force on the push rod to get 0.012 compared to the others.
    Bobby told me there had been issues over time with the valve seats moving and reducing push rod clearance.
    Later this week I plan to examine #4 with a boroscope and then pull it.
    I will post when I know more. Jake #175
    Last edited by 1473C; 06-20-2016 at 05:25 AM.

  2. #2
    Senior Member Clay Hammond's Avatar
    Join Date
    Feb 2010
    Location
    Salmon River Airfield, 9B8
    Posts
    280

    Default Re: Titan engine problem

    Great info Jake. Glad Titan was forthright and helpful!
    _______________________
    Clay Hammond

  3. #3
    Member
    Join Date
    Dec 2012
    Location
    Sangerville Maine
    Posts
    39

    Default Re: Titan engine problem

    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
    ,

  4. #4
    Senior Member ceslaw's Avatar
    Join Date
    Sep 2013
    Location
    Carterville, IL
    Posts
    589

    Default Re: Titan engine problem

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

  5. #5
    Senior Member c130jake's Avatar
    Join Date
    Jun 2012
    Location
    Minneapolis, MN
    Posts
    190

    Default Re: Titan engine problem

    I did my initial start on my EX today and #4 is bad too. New engine. Little egt rise. Checked plugs, ignition, removed primer. I will talk to Mitch tomorrow for more trouble shooting. I wonder if mine is doing the same thing. I know nearly nothing about engines.

    Jake Hayes

    Sent from my SM-G920V using Tapatalk
    Jake
    Finished CCEX N96FV!

  6. #6
    Senior Member Cubrath's Avatar
    Join Date
    Jun 2013
    Location
    Spearfish, SD
    Posts
    302

    Default Re: Titan engine problem

    Jake,

    Don't rely just on EGT. Probes could be loose or bad. Could be a loose ignition wire. What did it do? Mine was rough for the first 30 seconds then smoothed out. I'm sure Mitch will walk you through it.

  7. #7
    Member
    Join Date
    Dec 2012
    Location
    Sangerville Maine
    Posts
    39

    Default Re: Titan engine problem

    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
    Last edited by 1473C; 07-30-2016 at 08:29 AM.

  8. #8
    Senior Member
    Join Date
    Jul 2015
    Location
    Broken Arrow, OK
    Posts
    841

    Default Re: Titan engine problem

    Quote Originally Posted by 1473C View Post
    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?

  9. #9
    Senior Member c130jake's Avatar
    Join Date
    Jun 2012
    Location
    Minneapolis, MN
    Posts
    190

    Default Re: Titan engine problem

    Ran rough, #4 was cold to the touch while the other three were hot. Plugs were wet, swapped plugs with #2, no change. Checked for spark, rechecked electronic ignition. Ran the same on left, right, and both.

    Sent from my SM-G920V using Tapatalk
    Jake
    Finished CCEX N96FV!

  10. #10
    Senior Member Cubrath's Avatar
    Join Date
    Jun 2013
    Location
    Spearfish, SD
    Posts
    302

    Default Re: Titan engine problem

    I'm no engine expert either but it sounds like an ignition problem to me if the plug is wet. Did you try running on the left ignition box then the right? I would also check all your connections in the electronic ignition. My bet would be the #4 ignition coil in the front of the engine. Swap it and see if the problem follows.
    Last edited by Cubrath; 06-22-2016 at 09:01 AM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •