Carb Icing and Aeroinjector

[borrisl]

I've been running the marval carb on my C-85 stroker since new. For heating the carb I use https://www.aircraftspruce.com/pages/ep/carbheat/variezelongezcarb.php hotbox from Aircraft Spruce. This issue is, I ceramic coated the exhaust. The positives are that my CHTs are always perfect. Never even come close to overheating. The bad is that hardly any heat come off of the exhaust pipes. Therefore, pulling the carb heat increases carb inlet temp by 1 paltry degree. 

 

My thoughts are to go with the AeroInjector due to its ability to resist icing.

 

Any thoughts?

[Kent Ashton]

I have an Ellison.  They are said to be less affected by carb ice but it's hard to quantify.  Only twice in 600+ hours have I ever thought I _had_ any carb ice.  I really never use the carb heat except or rare occasions but I would be afraid to fly it in the winter without carb heat.  Maybe you just need to improve your heat muff or make a way to duct a little exhaust gas into the carb.

 

BTW, I have a friend in Vienna with a Cozy.  His Cozy is in France now undergoing repairs;  it'll probably be another year before he gets it home.

-Kent

Edited June 4, 2018 by Kent Ashton

[borrisl]

I've considered strongly the idea of removing the coatings from the exhaust in effort to restore some form of carb heat. Only issue I have with that is the heat on the engine is so perfect, why mess with something that "might" work.

 

I've also designed a heat exchanger that would be attached to the carb inlet and heated by oil. Then again I would have just created a failure point and possible oil leak.

Looked at electric elements, but only have an 8 amp alternator and would need 10amps for long durations. Heat up times are not always great either.

Thought about something like a PCV valve and induce some crankcase fumes into the inlet, but that might incur some oil mist.

 

Argh.