Rotax 532, 582 reduction drive troubleshooting
Rotax A and B reduction drive problems
When dealing with Rotax gear drives there are really three different drives. The first is called the "B". The B drive was found on all the old 532's. This drive used an adapter plate between the gear drive and engine. The adapter plate used four allen bolts to secure it to the engine. The gear drive then bolted on to the adapter plates using 4 of the 6 studs used to secure and fasten the two gear box halves together.
The most reported problem on the 532 was the loosening off of the 4 allen bolts securing the adapter plate to the crankcase. This can result in a broken crankcase, loss of oil in the drive resulting in seizure of the drive, or broken gear(s).
Another reported problem with older model engines is with loss of gear oil from the gear box. this is caused by pressure building up in the gear box and a siphoning action occurring through the vent cap.
The solution is to update to the newer style of Rotax gear box vent cap. It is a domed style cap that prevents this from occurring. Pilots have reported hard starting of their engines, or the engine not coming off an idle when it does start. This occurs when the springs inside the gear box weaken. I recommend replacement of the springs at 300 hours.
Also at 300 hours or at the first sign of wear I recommend the replacement of the two locking rigs that retain the output shaft gear in place. When replacing the two half moon rings check to make sure that the shaft area where they ride is still in good shape, and not worn.
At 300 hours I recommend that the bearings in the the be checked for wear and replaced if found to be worn or damaged. All seals and gaskets should be replaced as well.
Gear failure is especially the main gear is another area of concern. Failure generally shows up as chipped teeth on the gear which if not replaced will lead to the gear shattering. This is more apt to occur on craft using large diameter propellers or propellers hat are improperly balanced.
On late model 532 and all of the 582's the gear box bolts directly to the crankcase, using two bolts inside the gear case and six bolts on the outside. Thus the cases, and gaskets are different than those found on the 532. The gears, bearings, spring washers and shaft etc. are the same. So if you have a 582 all of the above reported problems other then the loosening of the allen screws are of concern.
The "C" and "E" Drives
The basic difference between the "C" and E" drives is that the "E" drive has a built in electric starter. The most reported problems with both drives is the failure of the seal which is located in the rear housing where the rubber donut is found.
Failure of this seal can generally be noticed when gear oil starts to show up in the two large hole found on the side of the gear box or when gear oil is found dripping from the back of the gear box. In one case that I know of the seal failed and gear oil exiting the drive landed on the exhaust system filling the cabin full of smoke.
It is a good idea to check this area on every preflight and at the first signs of leakage have the seal replaced. When replacing the seal check to make sure that the shaft does not have a ride on it where the seal rides. If it does try using a very fine emery paper to remove the ridge, or reverse the direction of the seal so that it has a smooth surface to ride on.
Failure of the rubber donut is another problem. Rotax has updated the donut several times. When ordering a new donut make sure to order it for the proper engine, different engines use different donuts. The use of the wrong donut can greatly effect engine performance.