O-360 Service Manual

[MikeOH58]

If anyone has the Lycoming Service Manual for a factory installed O-360-A4K for AA5B Grumman Tigers, I am trying to find both recommended, and max EGT/CHT's, and if the info is available, specifically for the # 4 cylinder.

 

[Blackhawk]

Service manual or operator's manual? I have the operator's manual for the -360 series. My aircraft has the AEIO-360, but the operator's manual is the same.
It does not show a maximum EGT except for the turbocharged models where it lists a maximum turbine inlet temperature of 1650F. CHT, it lists a maximum of 500F but recommends 150-400F for maximum service life. On my airplane I normall keep the CHTs in the 350 or less range; if it gets above that I try to take corrective action before 400. Not sure if this is what you were looking for.

 

[tgrayson]

If anyone has the Lycoming Service Manual for a factory installed O-360-A4K for AA5B Grumman Tigers, I am trying to find both recommended, and max EGT/CHT's, and if the info is available, specifically for the # 4 cylinder.

Do you mean the Operator's Manual? If so, I have it. The book doesn't provide operating guidelines per model, but only general recommendations for broad categories. For maximum service life of the cylinders, it says:

cylinder head temperatures should be maintained below 435 degrees F during high performance cruise operation and below 400 degrees F for economy cruise powers.
​

As for EGT, I believe the absolute numerical value of these are fairly meaningless, since the temperature depends strongly on where the probe is placed. The only thing that really matters is where you are with respect to peak EGT.

 

[MikeOH58]

Understood, thank you. Reason I am asking is because the # 4 cylinder was running an EGT of around 1480 at normal cruise settings....Higher than I ever remember me.

 

[tgrayson]

Understood, thank you. Reason I am asking is because the # 4 cylinder was running an EGT of around 1480 at normal cruise settings....Higher than I ever remember me.

http://www.sacskyranch.com/eng20.htm

 

[Berkut]

Are you saying that the high EGT on #4 is a recent thing? Has the CHT for #4 changed as well?

 

[MikeOH58]

Yes it does appear to be a recent thing...If my memory serves me correctly, i'm used to the # 4 running in the 1300's for EGT. And there has been no change in CHT.

 

[Berkut]

Well, I don't know the answer to your initial question about temp limits. But if you're interested in possible causes, my initial guess would be an induction leak. Have you noticed any change in the way it idles since the EGT problem started? Any roughness?