Modifying Robin Engine for Greater Slope Use?

ErikU · Mar 9, 2005

I was browsing Robin engines web sight, and they indicate they have full pressure lubrication. Wouldn't that mitigate any concerns regarding slope usage or am I missing something?

JerryG · Mar 9, 2005

A full pressure system means that it has pressure to all the vital components from the oil pump to those components. It still has to pick up the oil for the sump. That is where the problem is coming into play.

JackRobin · Mar 9, 2005

( A full pressure system means that it has pressure to all the vital components from the oil pump to those components. It still has to pick up the oil for the sump. That is where the problem is coming into play. )

That is 10000000% correct. /forums/images/graemlins/wink.gif

MossRoad · Mar 9, 2005

Think of it as sucking soda through a straw... your mouth get lubricated until the end of the straw is no longer submerged, then your mouth gets dry cause you're sucking air.

So take a large dish pan and put an inch of water in the bottom. Then stick a straw in the end of the dish pan nearest you. You can suck water with it pretty well. Then tip the pan away from you while keeping the straw in the same place. The water runs away from the straw. Tip it far enough and it will suck air.

That's the way oil pans work. The pickup is at the deepest point of the oil pan. Ever look at a car oil pan. It is deeper in the rear. That way if you accellerate, the oil is forced back and your oil pump keeps sucking.

With a small engine and the oil capacity at a couple of quarts, you could see how(using the dishpan example), depending on the placement of the pickup tube, the level of the oil in the pan, and the angle of the motor, you have a maximum angle that you can operate at before you start sucking air.

Charlie_Iliff · Mar 9, 2005

Ever look at a car oil pan. It is deeper in the rear. That way if you accellerate, the oil is forced back and your oil pump keeps sucking. 

Except the ones with the deep part in front because they had to clear steering or whatever. (Can't let logic and helpfulness go unchallenged /forums/images/graemlins/grin.gif)

ernemats · Mar 10, 2005

Jack:
What is the maximum slope for Robin engines to operate safely as far as lubrication goes?

pequeajim · Mar 11, 2005

( Jack:
What is the maximum slope for Robin engines to operate safely as far as lubrication goes? )

I'm curious about hearing the official word on that myself?

Also Jack, realistically, do you think there is any way to modify the engine for greater slope use?

JackRobin · Mar 14, 2005

The maximum operation angle is 25 degrees.

Regards,

Jack Gawecki
Robin America, Inc.
Technical Support Dept.
800-277-6246

Charlie_Iliff · Mar 14, 2005

The maximum operation angle is 25 degrees. 

I'm sure Jack will correct me if I'm wrong, but I assume that rating is for continuous use. Before anyone considers that as a serious limitation, I urge you to measure your slope(s). A brief tilt beyond 25 degrees won't hurt the engine, but I think I can guarantee it will get the operator's attention. 25 degrees is steep. You are likely to have traction and pucker factor problems before engine damage.
Jack certainly won't recommend this, but remember the ads for synthetic oil where they drain the crankcase and continue to run. With good oil, you can do that for quite a while - until something heats enough to cause damage. I've had engines run for a while on their sides, without discernable damage. The problem, of course, is knowing how long is too long, because too long is expensive.