Are Wankel Engines Easy To Repair Than Piston Engines?

Question

I Was Told By My Brother That Wankel Engines Blow Gaskets Way Too Easy.

Answer 1

The Wankel is a rotary engine, so rather than the piston going up and down, gasses are compressed by the rotation of a rotor. If it was a great engine, Mazda would have continued with research and Development and extended its use.

QUOTE:
The Wankel radial engine is a fascinating beast that features a very clever rearrangment of the four elements of the Otto cycle. It was developed by Felix Wankel in the 1950s.

In the Wankel a triangular rotor incorporating a central ring gear is driven around a fixed pinion within an oblong chamber.
END QUOTE

Mazda was the primary user, but they only use it in one produciton model and I think one racign vehicle:

QUOTE:
It is still used today, but only Mazda uses it, and even their funding for the R&D of the engine is quite limited, due to it only being used in one production car (at least at the moment.) My point was, what if rotary engines got the ind of attention from all vehicle manufacturers as the piston engine has.
END QUOTE

Problems associated with the engine are,

QUOTE
In practice, the main problem of the Wankel engine has proven to be the seals, and as of 2005 all proposed designs have some of the same potential weaknesses.

Although in two dimensions the seal system of a Wankel looks to be even simpler than that of a corresponding multi-cylinder piston engine, in three dimensions the reverse is the case. As well as the rotor apex seals evident in the conceptual diagram, the rotor must also seal against the chamber ends. Worse still, these two sets of seals must somehow join at sharp corners at the ends of the apex seals.

An additional problem is that the seals at the Wankel rotor apexes meet the chamber walls at an angle that varies plus and minus ~26 deg; during the cycle, while a piston ring meets the cylinder walls at a constant angle. As well as making the seal design itself more difficult, this means that while multiple rings are easily fitted to a piston, a corresponding approach is impossible with the Wankel apex seals. This limitation is addressed in the Quasiturbine AC design, but the simpler Quasiturbine SC design has the same problem of varying seal angle as the Wankel.

Piston rings are not perfect seals. Each has a gap in fact to allow for expansion. Moreover the sealing at the Wankel apexes is less critical, as leakage is between adjacent chambers on adjacent strokes of the cycle, rather than to the crankcase. However, the less effective sealing of the Wankel is one factor reducing its efficiency, and confining its success mainly to applications such as racing engines and sports vehicles where neither efficiency nor long engine life are major considerations. A further problem caused by the shape of the seals in Mazda engines is that carbon particles can become trapped between the seal and the casing, completely jamming the engine and requiring a partial stripdown to rectify. Wankel engines should never be started and run unless the engine will reach operating temperature; most such instances of jammed engines occur when a car is started and moved a few yards, e.g. from a garage to a driveway. In these situations it is better to push the car and not start the engine.

Another disadvantage of the Wankel engine in particular is the large surface area of the combustion chamber which reperesents a large heat transfer and quench area, combined with an unfavorably long and rather thin stretched combustion space, which means a long flame travel. The combustion is less complete than in, for example, an RPE, which has a more compact chamber shape with smaller area per unit of chamber volume. The Quasiturbine has similar disadvantages with its concave combustion chamber, and in the AC design the sharp angles of the carriers hamper the propagation of the flame front, leading to incomplete combustion.
END QUOTE
http://en.wikipedia.org/wiki/Pistonless_rotary_engine

QUOTE
Some of the problems have been sealing, emissions, fuel economy and durability. Mazda has done well with them in a very limited specialty market. They have spent about 30 years developing the rotary. FWIW, the 400 hp C6 Vette does 18/28 EPA estimates, while the 238 hp RX8 does about 18/24. Bet the Vette is LOTS quicker, too.
END QUOTE
http://web.camaross.com/forums/showthread.php?t=404763

Answer 2

That's not true Wankel engines can last almost as long as piston engines. but they will blow out apex seals if they run lean or if they over heat. These engines are very easy to rebuild but since they are a different engine than this just gives people an excuse to charge more money to rebuild them. A two rotor Wankel only has three moving parts and an average piston engine has over a hundred moving parts. if they blow gaskets way to easy than why is Mazda still racing with Wankel engines and why is Mazda still selling the RX-8 and spending billions in R&D? you can go to www.rotary engine illustrated.com thier they have a video showing just how easy it is to reabiuld a regular 13b engine.

Answer 3

Not really easy, your brother is right, the do blow seals and the early ones did it easily. The new ones don't though. The real hard part with these engines is the precision clearances in the combustion chamber. If you aren't a machinist or have access to a machine shop you have a big problem. On the up side a good Mazda rotary/Wankel will run many miles before needing work. The make lots of horsepower for their size and weight. They have been used in boat motors, by Mercury and Suzuki motorcycles offered a bike with a rotary engine for 1 year in the early seventies. A good way to learn about them is to get one out of a junkyard/recycling center and take it apart.Good luck

Answer 4

Rotary Engine Rebuild

Answer 5

The older RX-7 engines did have a problem with their eccentric seals inside the engine. But with proper maintainence, even the older cars will last 100K or more. They are harder to work on for a normal person, if you have to rebuild one.

Answer 6

For the best answers, search on this site https://shorturl.im/avETm

Piston engines are much more efficient, it's one of the reasons rotary engines never caught on, they get mediocre mileage.

Answer 7

a traditional engine will use less petrol compared to a rotary however a rotary will output much higher power/performance with less displacement so its going to depend on what type of driving u are looking to do