This is an excellet tool!  Very easy to use and time the engine with this.
Michael B
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
August 13, 2025
 
Easy to use
Scott S
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
July 29, 2025
 
As an A&P for 23 years Ive always hated timing Continentals.  Somehow Ive missed this tool till recently, then spent the last few months thinking No, it cant be that easy.    But I finally broke down & purchased this and discovered I was wrong.  It IS that easy.  Probably the best tool purchase Ive made in years
Rick D
July 26, 2025
 
Great tool! Accurate and saves a lot of time when checking magneto timing.
Herman H
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
December 14, 2024
 
Worked amazing on my Continental O470R that had no other timing marks on it.
Charles A
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
June 12, 2024
 
Works well and very simple to use. 
Adam 
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
April 27, 2024
 
Works great. Just put a little engine oil on the grommets and you are good to go, otherwise it is very difficult to get onto the bolts
Bobby M
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
December 5, 2023
 
Quick technique to see if mag timing may be an issue. 
Jared K
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
June 30, 2023
 
This FAA A&P,  the greatist thing since sex. Very easily used by the owner, check by the owner for engine timing, Change by A&P only. Many engine coughs and sputters affect engine timing, I could name 10 very quick. And keep you from walking home. Nice to have, 60 years ago. Worth $$$$. Havent checked Lycoming yet.. CH
Chuck H
November 2, 2022
 
These are a great quick reference for verifying timing. No complaints.
Eric S
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
April 23, 2022
 
Love this tool!
Samuel J
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
March 19, 2022
 
I saw an ad for this in the Cessna Pilot Association magazine and the ad said the tool for the 470/520/550 was also for the IO 360 ( which I have on my R172K Hawk XP) . Turns out that it works fine but with some exceptions. The clearance between the prop hub nuts and the front of the engine is too tight to insert the tool with the friction grommets in place. I removed the grommets and could slide the aluminum gauge in the gap and over the nuts. There was some minor side-to-side slippage, so I used some double sided foam tape to secure the gauge exactly when the #1 cylinder was at TDC to align the TDC mark on the gauge . Without the play, the 20deg notch was solid and good for timing the IO360KB engine. Happy with this 
Steve K
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
February 18, 2022
 
Works great with no moving parts!
Andy K
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
February 15, 2022
 
Great tool, everyone with a continental should have one.   Most A&P and IA have one
Dan B
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
February 10, 2022
 
Flying H
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
November 4, 2021
 
Awesome tool. Works great.
Keith P
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
August 5, 2021
 
nice tools ill be more precise while timing
Marc 
December 1, 2020
 
Great tool.  Works as advertised.  So easy, just set engine near tdc and slide gage over prop hub bolts.
One negative,  on Bonanzas where cowl does not remove,  they should print timing marks on both sides of gage for siting down the case centerline. I had to duplicate marks on other side of gage.  Still not a big deal.  So much easier than timing with a cone.  no leveling, no spinning prop. 
Green A
November 22, 2020
 
This is a great tool if you want to  do a quick check on your magneto timing for the recommended engines.
Stephen 
August 7, 2020
 
The O-300D has the same propeller bolt pattern an the O-470, IO-520,& IO-550 which is 6 1/2 holes in a 4 diameter.  The tool works on the O-300 D!
Alaska A
April 23, 2020
 
      I had set my timing using the older method. Then used this to check. I was very pleased how easy and I think more accurate using this tool is. There are too many steps in the old method where you can make 1 to 2 degree errors. This is right on. I use a mirror to sight down the spine of the case. Very accurate 
Joe F
April 22, 2018
 
  After using the flower pot and piston stop this tool is fantastic!  get #1 on TDC, Install this tool set 22 degrees and install and set the mags.   
Tom 
April 16, 2018
 
One of the most useful tools for working with Continental engines. Much better than the traditional timing indicator (dial on the prop).
A must have item due to its simplicity, ease of use and speed.
Mobile A
June 7, 2013
 
Arrived promptly. Compared tool with flowerpot timing device. Very accurate on the  O-300D. Tool fit and worked great. Only downside is the finish was rather rough. Appears to have been cut on bandsaw and had some sharp edges. Sanded down. Did not affect functionality. 
Daniel B
 Verified Purchase
Verified Purchase
Continental Engine Magneto Timing Tool O-300 C D / 470 / 520 / 550
June 10, 2024
 
      Doesn’t work on a plane with prop electric de-ice.
Craig 
May 27, 2019
 
Used 12-05514 timing tool one time and the magnet fell off during removal from the crack. It appeared the glue was brittle and applied with 50% coverage. 
Daniel S
January 20, 2023
 
Will only work on certain aircraft with access to the crankshaft hub. No can do on my Cirrus.
William T
April 12, 2021
 
Doesnt work on TCM O-300D. According to web site it does. Tool only lists 470,520 & 550 engines. Actual attempt failed.
Ed L
March 23, 2020