Re: Hard to start when engine is hot
Posted: Thu Jul 13, 2017 8:36 pm
Hi Mike, that is a great question.
I have been very fortunate with cool oil temps. I have determined that I have an error of around 10 degrees in my oil temp indications. My MGL Xtreme indicates 10 degrees cooler than the actual temps. I have never seen oil temps above 200 degrees (210 actual). Usually cruise oil temp is indicating 160 - 180 degrees. I will usually take off with oil temp indicating 90 - 100 degrees and then increase to around 190 indicated during the climb. That is with a climb speed of around 100 MPH.
CHTs have always been easy to control by adjusting power and climb speeds. I have not had a CHT go over 400 degrees in climb. Normally around 375-380 in climb. Cruise CHTs depend on how high a cruise RPM I use. When it is hot I usually keep my cruise around 3000 RPMs which has CHTs around 340 - 360. If I increase the RPMs to around 3200 - 3300 I will see CHTs around 375 - 380. So I usually cruse around 3000 RPMs when it is hot.
I have not flown my Sonex in the Months of June through September. It is too hot even early in the morning. When I do fly I don't like to start a flight if the temps are already above the low 80s and a I quit when It reaches 100. This is for my comfort. I think the plane would probably preform just fine if I monitor the engine temps and adjust accordingly.
I have been very fortunate with cool oil temps. I have determined that I have an error of around 10 degrees in my oil temp indications. My MGL Xtreme indicates 10 degrees cooler than the actual temps. I have never seen oil temps above 200 degrees (210 actual). Usually cruise oil temp is indicating 160 - 180 degrees. I will usually take off with oil temp indicating 90 - 100 degrees and then increase to around 190 indicated during the climb. That is with a climb speed of around 100 MPH.
CHTs have always been easy to control by adjusting power and climb speeds. I have not had a CHT go over 400 degrees in climb. Normally around 375-380 in climb. Cruise CHTs depend on how high a cruise RPM I use. When it is hot I usually keep my cruise around 3000 RPMs which has CHTs around 340 - 360. If I increase the RPMs to around 3200 - 3300 I will see CHTs around 375 - 380. So I usually cruse around 3000 RPMs when it is hot.
I have not flown my Sonex in the Months of June through September. It is too hot even early in the morning. When I do fly I don't like to start a flight if the temps are already above the low 80s and a I quit when It reaches 100. This is for my comfort. I think the plane would probably preform just fine if I monitor the engine temps and adjust accordingly.