Hi all
I have an RV4 with a carbureted Lycoming O320 A3B and I am having fouling issues despite agressive leaning. I started using TCP additive and it seemed to help but yesterday the engine was just generally rough and the lower #3 plug had liquid oil inside the plug when I pulled it. I just replaced the lower plugs with Tempest UREM37BY plugs to see if they help. A factor is that I generally fly below 5000 feet and most often around 1500 feet, any leaning at that altitude results in the occasional missing and rougher running. Flight profile is cross countries of 70 miles or less and aerobatics. It does have an air/oil separator.
The oil consumption is around 1 quart every 4 hours and there is oil coming out of the breather, I am running the level at 5 quarts to make sure excess oil is not being blown out. The 1974 remanufactured engine has around 750 hours so it has been standing for a substantial part of its existence but compressions are 76 to 78 on all cylinders so I don?t think rings are the issue.
I also flew a Beech Musketeer with an O320 and it was smooth as a sewing machine, much smoother than my engine and there was no need to lean it out to avoid fouling. I am going to speak to an engine shop but any suggestions or advice will be appreciated before I do so, I want to do a lot of troubleshooting before I take it in to the shop so I can eliminate the usual causes.
Thanks, Gary
I have an RV4 with a carbureted Lycoming O320 A3B and I am having fouling issues despite agressive leaning. I started using TCP additive and it seemed to help but yesterday the engine was just generally rough and the lower #3 plug had liquid oil inside the plug when I pulled it. I just replaced the lower plugs with Tempest UREM37BY plugs to see if they help. A factor is that I generally fly below 5000 feet and most often around 1500 feet, any leaning at that altitude results in the occasional missing and rougher running. Flight profile is cross countries of 70 miles or less and aerobatics. It does have an air/oil separator.
The oil consumption is around 1 quart every 4 hours and there is oil coming out of the breather, I am running the level at 5 quarts to make sure excess oil is not being blown out. The 1974 remanufactured engine has around 750 hours so it has been standing for a substantial part of its existence but compressions are 76 to 78 on all cylinders so I don?t think rings are the issue.
I also flew a Beech Musketeer with an O320 and it was smooth as a sewing machine, much smoother than my engine and there was no need to lean it out to avoid fouling. I am going to speak to an engine shop but any suggestions or advice will be appreciated before I do so, I want to do a lot of troubleshooting before I take it in to the shop so I can eliminate the usual causes.
Thanks, Gary