Coolant o-rings fail different from a head-gasket on a piston engine





When people say "it's like losing a head gasket" it's really not



Piston engine blown head gasket will see all 4 strokes, so sucking in and pushing out coolant



Rotary will only see 1 depending on where the leak is



Remember the engine has each part of the stroke process at different sides



You could burn coolant by having it suck in on the intake or combustion side of the motor, and you could force air and pressurize the cooling system if it's on the compression or exhaust side



I had a leak on the compression side of my motor

 

Basically what I'm getting at is if the leak is small enough, and it's, say, on the intake side of the motor, the engine would VERY slowly lose coolant from the reservoir, it would be burned, and because of the way the system is designed, it would draw from the reservoir back into the engine







So you might think you just have a leaky hose somewhere when your motor is actually burning it





Same idea on compression side



Mine only acted up when it was warmed up and driving for a while.. I kept driving and the seal got worse, and next thing I know I can't drive for 5 minutes without the system pressurizing and dumping all the coolant out of the overflow, weather hot or cold engine. There wasn't any debris in the coolant either. When a head gasket goes on a piston engine you get alot (more) of contamination.

 

when piston engines blow head gaskets thats what happens as well, its either blown out the exaust or its burned in the intake

 

If you're lucky