V-twin smoking at an angle

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harrisonaero

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My son and I restored my mini-excavator and used a HF 22hp Predator engine. Was a lot of work to get to fit but runs great... except when I tilt the excavator at an angle (tilts engine sideways) and then it smokes up a storm because oil is going though the PCV tube into the airbox/carb.

For those that have worked on a similar engine and situation <like for an ultralight> what did you do to the PCV to keep it from dumping oil when at an angle?

Looking for really simple solution- preferably one that doesn't require pulling the engine.
 

harrisonaero

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It's sucking in more than oil mist- raw oil is pooling in the carb. Happens when it's at an angle so I think it's a function of the PCV location. I'm looking at adding a simple crankcase breather but am open to additional suggestions.
 

akwrencher

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If it's overhead valve, can you add a pcv valve from a small car engine to a valve cover? Just a thought.
 

pictsidhe

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Depends where it is now. If it is on a rocker cover, putting one on the other rocker with pipes going up to a tee may do it. Have any pictures? Don't just disconnect it, the smoke signals are telling you when oil is going overboard.
 

Hot Wings

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Oil level too high? Even a little bit too high can cause problems when the crank starts dipping into the pool. Then it doesn't really matter where the vent is located. These industrial engines are generally designed with operation on a slant being considered normal but the oil level does rise relative to the crank when tilted. Also once the air filter element gets a little oil the problem just compounds.
 

harrisonaero

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Oil level might be a bit high, I'll check tomorrow. But lots of online places suggest that these engines aren't made to be operated at more than a 15 deg angle stock. Hence the search for a mod to allow to run at an angle. A breather on the PCV hose might do the trick but I'm just checking to be sure (hopefully someone else has already done it successfully on this engine).
 

markaeric

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Easiest mod would be to remove the line from the crankcase and replace it with an elevated filter, and then plug the carb side. The more proper solution would be to install an oil catch can.
 

harrisonaero

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Easiest mod would be to remove the line from the crankcase and replace it with an elevated filter, and then plug the carb side. The more proper solution would be to install an oil catch can.
Yaa, thanks for that. Probably the way I'll go to start. I think I found some online info from the mower guys that had the same problem when they were on hills. Anyone that uses this engine for an UL will have to deal with it as well of course.
 

BBerson

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My Honda V-twin doesn't blow anything out the breather in static full power runs at 15°. (Taildragger)
It might in a 15° power dive but I don't anticipate doing that.

I was watching a Sopwith Pup run at the Westerm Museum Saturday. It had the total loss oil system with no catch can!
 

Hot Wings

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My Honda V-twin doesn't blow anything out the breather in static full power runs at 15°. (Taildragger)
I think the OP is having problems along the roll axis not the pitch?

It could be that an internal baffle/shield may be needed for the crankcase vent? If the reed valve is working it really shouldn't be needed.
Predator_000012.jpg
 

BBerson

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Looked like most of the oil slings outward and sticks inside the cowl ring. I walked behind and through the prop blast just to experience the massive thrust from the 9 foot prop. Didn't get any oil on me.

The exhaust valves opens direct to the wind. They prime it for starting with two squirts of raw gas into each exhaust valve (9 cylinders) held open by hand easily.
Then it starts on first flip every time.
 

harrisonaero

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Just an update... ordered a $8 K&N breather filter and installed it just above the engine and it did the trick. Won't smoke at any angle and the excavator runs just fine. The 22hp engine seems to be a good replacement for the 15hp diesel that use to be in it. I put on a digital tach and set the RPM to 2800 max (with a placard to remind me) to keep the hydraulic pump speed down to about what the diesel ran so the extra v-twin speed/hp isn't really being used. Now to go dig some dirt...
 
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