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LO-360 Conversion

J

Johnny Be Good

Active Member
Greetings. I have searched the forums but not been able to find any relevant posts. My question is can a counter rotating LO-360 engine be converted to rotate in the traditional way and what is involved? Thanks in advance. John
 
Johnny Be Good said:
Greetings. I have searched the forums but not been able to find any relevant posts. My question is can a counter rotating LO-360 engine be converted to rotate in the traditional way and what is involved? Thanks in advance. John
Click to expand...

John,
I'm sure it can be done, but not sure how many parts would need swapping out. Cams for sure and maybe the crank too?

Question...why not get Craig Catto to make you a prop that spins correctly for the engine and use the engine as is? I'm sure it would be cheaper in both the long and short terms. Yeah, you'd have to input left rudder on takeoff instead of right, but I'm sure you'd adapt quickly. Guys with Mazda rotary engines have to do this too, so it's not unheard of.
 
You would have to be sure about a few things,

Gear train, is a gear installed to counter rotate the gear train?
If not that could affect oil pump, and mags.

Camshaft for sure.

I don't know if your engine has offset piston pins, but if so the pistons would have to be rotated 180 deg on the rods.

Crank - would not think so unless drive gears are affected.

Good luck, an interesting change.
 
Thanks Michael and Bill,

So what you guys are saying is that although it can be done, buying a counter rotating engine as a core is not really a viable option.

Michael, I fly a Rotax 582 powered microlight that turns the "wrong" way here in Zimbabwe so that wouldn't worry me but I would prefer to keep my RV conventional for future resale value and to keep costs down.

Thanks again.
 
'Lotta' Work!
The engine is offset a few degrees for the right hand prop. The offset would be to the other side for a left hand prop. I Know, I had a Mazda Rotary on my RV-8. It had a left hand prop. I had to mix up some epoxy filler to fill the wide gap behind the prop spinner on the right side.
When I removed the Mazda, and installed a Lycoming, I had to cut, grind & sand out the filler so the prop & spinner would fit VAN's original cowl offset.
You would also need a special motor mount to provide the left offset, yet position the prop in the center of the cowl.
Otherwise, you would develop a very large muscle in your left leg!
 
LO 360 conversion

I spoke with Lycoming concerning this issue very recently. The crank itself is not compatible due to the way it is machined. Specifically, it has to do with the lubrication holes in the journals and, probably, the position of the dowel pin on the rear of the crank. The bushings on the flange may be located differently, as well, though they were not sure without looking at prints.
 
engines

There are several things that are different.
crank
cam
accessory housing
oil pump housing
mags
The case, gears, rods, sump and intake would all be the same.
I have seen factory Lycoming engines come in with the wrong direction crank so I don't think that will hurt anything. Having to purchase the other parts would probably make the deal not as sweet unless it was free.

Jesse
 
Mountint a Leftie

To the idea of mounting & using as is... the engine mount would have to be modified from down/left offset to down/right & vertical fin mounting plate changed for the angle offset to other direction. You would probably have some extra minor glass work on the cowling also & of course a custom prop. Would be perfect setup for Down Under!
 
It works in the Northern Hemisphere too, you just fly backwards :p .

Being serious now, I've flown a plane that spins the engine the wrong way. A few minutes into the climb, I realized I was pushing on the other rudder pedal. That's when it dawned on me "duh, I knew it spun backwards".

My concerns in an RV, (really any plane designed for a right turning engine) would be the vertical fin offset. In our RV world, the engine mount would also be quite an expensive proposition to get one custom made.
 
Get the parts manual for that engine. It will have the parts listing for the "straight" engine also. Compare the parts. Some conversions are complicated others are simple. Piper sold a kit to convert the Twin Comanche to counter rotating. It was fairly simple to do.
 
LO-360 Conversion.

Thanks to everybody for the input. The engine I have been looking at came from a Comanche so it might be an option but really it seems that it will be more trouble and cost than it is worth....

Regards

John
 
Leftie

But if the engine deal were really really good - turning a leftie prop wouldn't be that bad. You'd be in line with all those Yak drivers & radial Pits etc!
That engine also had Dynofocal 2 mounts, so figure that geometry into a modified mount too. And you would have to change the oil pan to either up draft or forward facing intake. Could be done.
 
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