Author Topic: Franklin 90hp Engine?  (Read 4190 times)

Scott Crosby

  • *
  • Posts: 22
    • View Profile
Franklin 90hp Engine?
« on: December 29, 2011, 03:31:28 PM »
Thanks Bill for starting this forum!  I'm not only new here but I just recently purchased Culver Cadet #457 N41735 - a project that hasn't been in the air since 1960! My plane came with an overhauled 90hp Franklin 4AC-199. My first thought was to find/build an LCA mount and go Continental but maybe I should rethink this and consider using the Franklin. My question is for you guys flying Culvers with the Franklins. What are the pros and cons?  Are they capable of being a reliable and safe engine?  What about parts availability?  Would you go Franklin again?
I think I'm looking at an excuse to keep the original Franklin if I can justify it.
What do you who know think?  Any and all opinions will be appreciated.

Thanks very much,
Scott Crosby

Woody

  • Jr. Member
  • **
  • Posts: 84
    • View Profile
Re: Franklin HP Engine?
« Reply #1 on: December 29, 2011, 04:38:45 PM »
Scott,
 I just got home with a Franklin 90 that came with the plane.  It has been stored since 1964 and has 30 hours on it.  I did just like you but decided to stay original.  Depending on the condition of the engine, a lot of the parts are still available.  I just bought a Franklin 65 also in case the crank/cam was not good.  They carry the same crank from 65 through the 90. Delivered cost was very small.  Franklin has a real good reputation and is smoother than most others.
woodys culver rebuild.com            Will have new pictures posted in a few days.   Woody

Dan C

  • *
  • Posts: 11
    • View Profile
Re: Franklin 90hp Engine?
« Reply #2 on: December 31, 2011, 10:06:51 PM »
I recommend that anyone planning to own and operate the 90 hp. Franklin, obtain the manual for the 4AC-199 series. Read it and understand it. Franklin had some different ideas on building an aircraft engine. These engines have been around quite a while and too many "farmyard mechanics" have had their "fingers in the pie."
I have a fair amount of experience with the six cylinder Franklins, both pre and post war. Now, I too have inherited a "90."
Who knows what I'll put it on.......
Dan   

Paul Rule

  • Jr. Member
  • **
  • Posts: 80
    • View Profile
  • N Number: N37814
Re: Franklin 90hp Engine?
« Reply #3 on: January 04, 2012, 04:31:13 PM »
Franklin 90 is a good engine... just won't last as long as a Continental.  Nothing wrong with that,  it will give you plenty of warning as the rings and valves seem to be the first to go.  Just do regular compression checks. 

I have a Franklin 85hp (which is just the 75HP spun faster) that has 1300 hrs on it and has been topped 3 times without spliting the bottom end. 

Also, wood props ONLY!  Metal props are not approved on the 90hp for sure (but also on the 75 /85 I think).  The crank is lighter and will eventually break.