Cool Jugs ?

[fairchild]

Saw a web page for a product called "cool jugs" . Basicly they are a completely water cooled replacement jug for lycomings. Come with a water pump
and associated hardware. Not an approved part so far so experimental only. According to what i saw-
The good- uniform engine temps, no inlet drag- 10-15 knott increase, reduction of fuel consumption by like 38 % - no weight penalty vs. air cooled..... about 15-20 HP increase....
The bad- about 15-to 18K $ costs all most as much as a new engine...... I dont see how that will ever "fly" so the speak..... at that price point.....
Looks like a good idea maybe ........
Too rich for my blood ! :-)
Tim

[Chris In Milwaukee]

I've been watching them on and off for several years, and even exchanged emails a while back with the owner. I think it's a good idea, but you're right. It's spendy. Up here on the Frozen Tundra, though, I can certainly see its benefits. I find myself reading through their info at least once a year.

[marcusofcotton]

So how does one add a double jacket, water pump, hoses, radiator, all filled with coolant, without adding weight? Certainly merit to the idea, but I don't think I'll be investing in it soon.

[whee]

Their website says a 38lb weight gain over air cooled for the 4 cylinder but with 15% more hp from the increased compression it more than makes up for the weight....so they say.

Cool idea. Franklin converted one of their engines models to water cooled back in the 50s for automobile use and I always thought it would be cool to see how they did it.

[marcusofcotton]

Thanks for correcting me, I thought I had read earlier that they said no weight gain. I wonder how many have been installed and what the track record has been.

[Zzz]

It's definitely beneficial for the Rotax 912, which I always say I would buy in an instant if there was a 250 hp version. The benefits are undeniable, but retrofitting to a Lycoming seems questionable, especially the 38 lb gain part.

[Battson]

But you can shed all that extra weight so easily with an MT prop?

Besides, after all that, your wallet will be so much lighter - you will have no weight troubles to worry about.

[Bdflies]

Really neat idea, but it raises more than a couple of issues; to really increase the power, appreciably, how high would one bring the compression ratio? To produce more horsepower, does one increase the RPM or torque? Gotta be one, or the other, or both. Either way, what effect will the increased stress have on the internals and crankcase? Ever seen a cracked case? I have. Cooling drag might be reduced, but not eliminated. Radiators still create drag. Fuel consumption could be reduced, but just how much? I flew a Rotax 912 (80hp) about 400 hrs, burning about 4 gph. What's the fuel burn of a C-85? Pretty close to the same, I'd imagine. Without computerized efi and knock sensing ignition controls, I question the fuel saving claims. Faster? Maybe. But, think about this: I'm gonna run a Lycoming, with significantly increased compression, experimental water cooled cylinders, experimental computer controls. I'm gonna turn this thing 3,000rpm, to make more power. Talk about EXPERIMENTAL aircraft!

Now, don't get me wrong. I'm being intentionally pessimistic, to play the spoiler here and stir the conversation. I'd be thrilled to have a proven water cooled engine option. Remember the water cooled engines that Continental perovided for Rutan's Voyager? What happened to that?

Bill