View Single Post
Old 10-26-2019, 01:22 PM
Scott Hersha Scott Hersha is offline
Join Date: Jan 2005
Location: Cincinnati, OH
Posts: 2,356

Another thing to consider is what prop you have. If you have a light weight prop, it might not have enough flywheel effect to carry it through the compression stroke. The newer versions of the Pmag software automatically retards the spark to 4* after top center when the start timing is set to TDC. This should prevent kick back. It sounds like you are fuel injected. If that?s the case, you shouldn?t need any prime at all to start the engine if it has been run in the last 2 hours or so. There?s plenty of fuel in the spider to get the the engine started. Leave the mixture in idle cutoff, crack the throttle, and hit the starter. When it fires, slowly bring the mixture out of idle cutoff. No boost pump needed. EI systems start the engine much leaner than mags. You can ?fool? the Surefly into starting at a few degrees after TDC and it shouldn?t affect the ?run? timing. After I installed two Pmags on my previous (RV8) airplane, we had two kick backs with a lightweight Whirlwind prop. The second one broke a few teeth off my starter ring gear. I reset the timing to an extra 2* after TDC. It started fine and I never had another kickback event.
RV6/2001 built 2000/sold 2005
RV8 Fastback/2008 built/sold 2015
RV4/bought 2016/sold/2017
RV8/2018 built/Sold(sadly)
RV4/bought 2019/sold2021
RV6/August 2022 build - Phase 1
Cincinnati, OH/KHAO
Reply With Quote