Removing Gearbox

I'm attempting to remove the gearbox for the Flywheel upgrade on my 110 engine but I'm running into trouble.  The gearbox is completely disconnected except for the connection to the rubber couplers.  I've tried everything I can think of to get the gearbox off, but it seems to be welded to the couplers.  Has anyone else run into this problem and come up with a method that works?  Any help will be appreciated!


You need to be a member of Viking Aircraft Engine Forum to add comments!

Join Viking Aircraft Engine Forum

Email me when people reply –


  • Congrats to you
  • Doing my flight training in a Citabria.
    Lots of fun, but have had some delays due to bad weather and busy schedules.
    I expect to have my BFR sign off in early January.
    Really looking forward to flying my Viking Waiex.
    I hope to see you all at Oshkosh 2017!
  • Congrats to you Don, too. Hope your BFR training is going well.
  • Congratulations, Don Bowen! Time to fly it!!!
  • Today I finished the flywheel and gearbox upgrades on my Viking 110.
    I have photos and text from start to finish.
    My web site is
    Look for the button that says "Flywheel Upgrade".
    I am really happy with this upgrade, the steel parts are very nicely made and appear to be stronger and more durable than the aluminum.
    Many thanks to Jan and Samantha for all their kind help and guidance during this upgrade.

    See you at Oshkosh!

    Don Bowen
    Viking Waiex N49YX
  • I got it off. I removed the 3 nuts on the flywheel spider and pulled and pried until it came off. It was quite a workout. Removing the flywheel was easy in comparison! Thanks for the help!
  • Dale I had the nuts and bolts holding the spider drive on in my 110. I took all of them off and just started wiggling the gearbox around. I could feel very little movement at first but after about 30 minutes I got it broken loose and off. I just got my new flywheel and upgraded gearbox back just before thanksgiving. Now I've got to get out and re-install it.
  • You need to remove a minimum of 3 nuts from the bolts holding the couplers. Or, if you already have the pin system, without the nuts, it is being held by the center pilot bearing only.

    Get an 8 foot 2x3 and devide into 3 sections.
    Get some help and pry between gearbox and flywheel from 2 or 3 directions while someone (or a table) catch the gearbox as it come off the engine.

    With the latest system this is no longer an issue because a replaceable plastic alignment bushing is used, rather than a bearing
This reply was deleted.


Michael Teodori is now a member of Viking Aircraft Engine Forum
21 hours ago
Eric Johnson posted a discussion
My Zenith 801 is going together, wings are on and I ran it with the propeller on for the first time last week. I added pre-filters as recommended to the fuel lines going to the header tank and started my fuel flow tests tonight.Initially I put on WI…
Randall Haney updated their profile photo
Rheal Comte updated their profile photo
Jul 5
Barry Kropelin is now a member of Viking Aircraft Engine Forum
Jul 5
Matthew S. Whiting, P.E. is now a member of Viking Aircraft Engine Forum
Jul 3
Jim Owens updated their profile photo
Jul 2
jeff is now a member of Viking Aircraft Engine Forum
Jul 1
Jeff Roberts updated their profile photo
Jun 24
Jeff Roberts is now a member of Viking Aircraft Engine Forum
Jun 24
Frank is now a member of Viking Aircraft Engine Forum
Jun 7
Mike Drew updated their profile
Jun 4
Viking Aircraft Engines replied to Branden's discussion Viking Engine in a RANS S-21
"We do have some installations here. Alissa at Viking can get you contact info of these great builders and pilots
Performance is close to the Titan engine, even with the 130. Adding our latest development of a variable DUC propeller makes it a perfe…"
May 23
Branden posted a discussion
Hi all,I'm very curious about the Viking engines for the RANS S-21. Anyone else building a S-21 considering a Viking? 130 vs Turbo? I've seen the S-20 with the 141 wing on Youtube and it seems you get good performance with the 130. I'm also consider…
May 23
Glenn Davis posted a discussion
Jan, I have added inspection and cleaning of the internal filter in the fuel pump to my annual list. Can you explain how the filter is accessed? Glenn Davis
May 15
Manjulal is now a member of Viking Aircraft Engine Forum
Apr 30