Walt Shipley
Active Member
My engine in my RV-12 is running rough and so far, I haven't been able to
determine the problem. At first I thought I just needed new sparkplugs, but
after installation of new plugs, engine still ran rough.
Next, I spoke with Lockwood and they thought it might be carb related, since
I was right on the 200 hour mark and a carb overhaul is due at that point. Had the carbs overhauled, engine still ran rough. But, after shutting engine down,
I felt the exhaust pipes coming from each cylinder and the pipe from No. 1
cyl was cool to the touch while the other three were hot.
Next I did a compression check and cyl No. 1 was normal 75/80 cold. I also
pulled the valve cover from cyl 1 and the valves opened and closed as the
prop was rotated.
Called Lockwood and they advised to try and snip 1/8" off both No.1
sparkplug leads (sparkplug end) and reinstall on plug connector. They
also advised to ohm out the spark plug leads and check trigger gap for
.012".
Started engine after snipping the plug leads, still runs rough. Haven't done
the ohm checking yet.
From this information, do any of you have a suggestion as to the cause of
my problem? It seems almost inconceivable that I can be having a problem
with both ignition modules at the same time.
Thanks for any help you might give.........
Walt Shipley
determine the problem. At first I thought I just needed new sparkplugs, but
after installation of new plugs, engine still ran rough.
Next, I spoke with Lockwood and they thought it might be carb related, since
I was right on the 200 hour mark and a carb overhaul is due at that point. Had the carbs overhauled, engine still ran rough. But, after shutting engine down,
I felt the exhaust pipes coming from each cylinder and the pipe from No. 1
cyl was cool to the touch while the other three were hot.
Next I did a compression check and cyl No. 1 was normal 75/80 cold. I also
pulled the valve cover from cyl 1 and the valves opened and closed as the
prop was rotated.
Called Lockwood and they advised to try and snip 1/8" off both No.1
sparkplug leads (sparkplug end) and reinstall on plug connector. They
also advised to ohm out the spark plug leads and check trigger gap for
.012".
Started engine after snipping the plug leads, still runs rough. Haven't done
the ohm checking yet.
From this information, do any of you have a suggestion as to the cause of
my problem? It seems almost inconceivable that I can be having a problem
with both ignition modules at the same time.
Thanks for any help you might give.........
Walt Shipley