Rotax 532, Rotax 532 aircraft engine rebuilding manual, 532 Rotax engine reassembly.



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Rebuilding the Rotax  532 ultralight aircraft engine.

Reassembly -Rotary valve shaft installation

Tools Required
extrusion jig
hot plate
oil container

Shop supplies
Loctite (red)

Rotary valve oil seal
O ring
Compression spring

Apply grease to lubricate the lips of the rotary valve seal. Install the seal onto the shaft. Heat a small quantity of your two stroke engine oil to 200 degrees F. Submerge the rotary valve shaft bearing in the oil for approximately 5 minutes. Install small quantity of Loctite 648 onto shaft where bearing will ride. Using gloves remove the bearing from the oil and install it on the shaft until it rests against end of shaft cut out. Install shim. Apply a small quantity of Loctite 648 green to the shaft area immediately in front of the shim,

Rotary valve shaft installation

install spacer. Rotate the spacer to distribute the Loctite evenly. Install shim. Install rubber O ring. Install gear. Install spring. Install spring holding cup. Using spring holding cup compress spring. Install circlip, make sure that it seats properly.

Bearing installation
place upper crankcase halve into oven at 200 degrees F for approximately 5 minutes. Remove from oven. Using bearings insertion tool, and hammer inset rotary valve shaft bearing into crankcase half, from carburetor side of crankcase.

Reassembly -

Crankshaft and crankcase preparation

Tools Required
10 mm socket
13 mm socket
6 mm allen wrench
Screw driver
Rubber mallet

Parts required
830 747 PTO seal 1
831 950 MAG seal 1
Bearing O rings
Spacer block O ring

Shop Supplies required
Loctite 515
Loctite ()

Seal preparation

Before installing the two seals on the crankshaft first lubricate the interior lip of the seal with a light coating of grease to ensure proper lubrication on engine start-up.


Crankshaft/crankcase preparation

Lower Crankcase preparation

To ensure proper seal between the two crankcase halves it is necessary to use a crankcase sealing material. The recommended sealant is Loctite 515 Gasket Eliminator.

Apply a bead of 515 to the sealing surface of the bottom crankcase half. Then using your finger spread it around until all the sealing surface has a nice even coating.

Crankshaft preparation

Install new O rings on the crankshaft bearings, and on the aluminium spacer block,
Apply Loctite 515 Gasket eliminator to sealing surface.


:the ring for the aluminium spacer block is thicker.

Reassembly - Crankshaft installation, case reassembly

Grasping the crankshaft by the ends lift it up and place it into the upper crankcase half. Align the center crankshaft locking rings, with the crankcase cut-outs, and the O ring, and magneto seal with the seal alignment grooves in crankcase.

Tools Required
10 mm socket
13 mm socket
6 mm allen wrench
Torque wrench

Crankcase Reassembly

With the crankshaft installed in the upper crankcase, place the lower crankcase onto it. Install the 13 mm lower crankcase retaining bolts, 6mm allen head bolts then the 10mm socket head bolts. Snug the bolts up but do not tighten them.


Be sure water pump side bearing is in place, or you will have to split cases to install.


All lock washers used on Rotax engines go with the points at the openings of the washer facing disposable parts. All washers should face the bolt heads, or nuts during installation.

Reassembly - Stator plate installation, torquing cases

The stator plate is used to align the crankcase halves. Install the stator plate, feed the wiring through the hole in the crankcase. Line the stator plate holes up with two holes in the upper and lower crankcase halves. Install the 2 allen head bolts, and snug them up. Check the alignment of the two crankcase halves by running your finger along the seam between the two halves. It should be even. If not then gently tap the casings with a rubber hammer until proper alignment is obtained.

Torquing the crankcase

Use a torque wrench, and in three stages, torque in an X pattern from the center out torque
Install the rubber grommet protecting the wiring harness.

Torque 8mm bolts first to 70 inch lbs, then 140 inch lbs, then 195 inch lbs. Torque 6 mm bolts to 88 inch. lbs

Reassembly - Piston, pin, bearing, clip, base gasket

Tools Required
Circlip installation tool or flat screwdriver
pair of pliers with rubber coated handles
Oil can

Parts required
Wrist pin bearings

Piston installation

Position the engine so that it rests on the lower crankcase half. Move the connecting rod to top dead center.

Install the wrist pin bearing into the top of the connecting rod. Using an oil can lightly oil the bearing. For cageless bearing installation refer to page K -09A.

Pick up a piston, with the arrow on the dome of the piston pointing towards the exhaust port of the engine, and the circlip hole with no circlip in it facing outward start the wrist pin into the hole until it just protrudes past the inside boss.


New style piston has hole in intake side, for better bearing lubrication.

Reassembly -Piston, pin, bearing, clip, base gasket

Slip the piston and pin assembly over top of the connecting rod and bearing. Looking through the wrist pin hole from the other side align the pin with the bearing and push the wrist pin gently through.

With the wrist pin installed, using a new wrist pin clip and installation tool or screwdriver carefully install the clip into the wrist pin clip retaining groove so that the opening in the clip is facing towards bottom of the piston.

Repeat the process for the other piston.


The arrow or AUS mark on the dome of the piston points towards the exhaust side of the engine.

Caution: Install the wrist pin clip so that the opening in the clip is facing towards the bottom.

Reassembly - Cageless bearing installation

Tools Required
Polystyrene or polyurethane plug
Crankcase cover template
Shop supplies


Using templates found on page (), make up cover plates from cardboard. Install these over aperture, in crankcases. Move mag connecting rod to TDC. Apply grease into connecting rod end. Install 15 of the needle rollers into the bottom half of the connecting rod end. Insert special plug, (18 x 22mm) in diameter. Insert the remaining needle bearings. Install the thrust washers on both sides of the needles.

Piston installation:

Install wrist pin till pin is flush with piston hub. Ensure arrow on piston dome is pointing to exhaust side of engine. Align pin up with connecting rod hole. Push pin through, while pushing plug out. Install new wrist pin clips. Repeat for other side.

Note: For this installation procedure 4 wrist pin clips are required.

Reassembly -Ring and base gasket(s) installation

Tools Required
Fingers, eyes

Parts required
Top rings
Bottom rings
Cylinder base gasket(s)

Ring installation

With the pistons, pins, and clips installed. Install the lower ring. Looking at the ring note one side has writing on it, this is the top side of the ring. With the writing facing up use you fingers to gently pry the ring over the piston and into the lower ring groove. Once installed rotate the ring until the opening in the ring aligns with the ring dowel pin. Now using your fingers install the top ring, and position the opening in the ring so that it also faces the ring dowel. Once the rings have been installed make sure that they move freely, with no stickiness or binding.

Place the cylinder base gasket(s) onto the 4 cylinder studs, (newer engines uses allen screws, and a one piece gasket which is placed on the upper crankcase half and slide them (it) down until they (it is) are flush against the crankcase. Repeat for the other side

Reassembly - Cylinder installation

Tools Required
Tool # H4440
hands and fingers

Cylinder installation

With the rings installed, and properly positioned in the ring groves, place a pair of pliers with rubber coated handles/or tool H4440, so that the connecting rod is between the two handles, slowly lower the piston until the piston skirt is resting on the handles.

Picking up a cylinder and using a lightly oiled rag, oil the bottom of the cylinder. Then with the arrow on the piston dome facing towards the exhaust port on the cylinder, gently lower the cylinder down over the top of the piston.

With your fingers come in from the sides of the piston and gently squeeze the top ring together until the cylinder slides down over it.

Repeat for the bottom ring. Then slide the cylinder down, while removing the pliers/tool.

Repeat for the other side.


Make sure that the ring is positioned with the opening of the ring on each side of the piston dowel.

Reassembly - Cylinder installation

Tools Required
Cylinder alignment bar
torque wrench
6 mm allen


Prior to installation of the cylinder head it is first necessary to properly align the cylinders, and then torque them. On some model engines, the cylinders were held in place with 8 flat washers and 8 dome nuts.. Other models had dome nuts\B \with flat bottoms, located on studs protruding from the upper crankcase half newer models have allen screws and washers, while the latest use 12 mm cap nuts. Which ever your engine has install them and then snug them up. Once snug install the cylinder head, upside down onto the head bolts , or install the cylinder alignment bars. This will correctly position the cylinders. Gently remove the cylinder head. Now using a torque wrench in three stages, using the pattern in Fig A torque the nuts to specifications. If alignment bars used remove them now.


There are two types of alignment bars, one fits on to the top of the cylinder head studs while the other bolts to the exhaust manifold.

Reassembly - Cylinder head installation

Tools Required
13 mm socket

Parts required
2 sealing rings
2 O rings


With the cylinders properly aligned and torqued place the two outer sealing rings into the grooves on the top of the cylinders. Install the two inner sealing O rings. Carefully place the cylinder head onto the top of the cylinders, while holding down on the head install two nuts finger tight. Install the rest of the nuts snug them up, then in three stages torque the nuts in three stages using the torque pattern shown in fig A. For torque specifications refer to section N -01.

Reassembly - Magneto installation

Tools Required.
Lower magneto puller ring
3 proper length bolts
Torque wrench
30mm socket


Before installing the magneto check to make sure that the screws holding the stator unit, points and coils are tight, and that no wires have been pinched or cut during installation. Carefully place the magneto onto the crankshaft magneto end, aligning the magneto key way cut up with the crankshaft key.

Install the lock washer, onto the crankshaft, with the locking points facing towards the nut, install the nut.

Install the lower halve of your magneto puller, using 3 bolts of the correct length, locking it into the lower crankcase half, as per Fig 3c Prior to tightening up the three bolts install the 30 mm socket to align the puller. Using a torque wrench torque the magneto retaining nut to 65 ft. lbs. Remove the lower magneto puller half.

Reassembly -Ignition timing.

Tools Required
Flat blade screw driver
Dial indicator
Buzz box or continuity light
Feeler gauges
Business card
4mm Allen wrench

Parts required
grease for phenolic block assembly


To check the timing, place your dial indicator into the spark plug hole in the magneto cylinder. Connect your buzz box to ground and to the magneto side coil wire, this is the blue on black wire. Turning the engine over clockwise bring the piston to top dead center. Zero the dial indicator.. Turn the buzz box on. Now turn the engine counter clockwise. The Buzz box should indicate the ignition is firing at .077 before top dead center.

Engine Rotation

Normal engine rotation is clockwise when looking at the magneto.

Reassembly - Ignition timing.

To set the ignition timing it is first necessary to set the point gap to .015 thou. on both cylinders. To do this center the stator plate on the two retaining screws. Turn the engine over until the point gap on the top set of points is at its widest gap. Using a set of brass feeler gauges, and a blade screw driver, come in through the cut out in the magneto and adjust the points until a .015 thou gap is obtained. Point adjustment is accomplished by loosening off the point retaining screw and placing the screw driver into the point bracket adjusting hole, one way opens the points while the other closes them.

For point and condenser installation refer to Section L -07. Repeat for the other cylinder.

Install your dial indicator into the magneto cylinder spark plug hole . Turn the engine over clockwise, until the magneto piston is at top dead center. Zero the dial indicator. Connect the buzz box to the blue on black wire coming from the magneto. Turn the engine clockwise and note the firing position. Point gap .015. Lubricate felt pad Ensure felt pad angles away from rub block

Reassembly -Ignition timing
If the engine is firing too early move the stator plate clockwise. If the engine is firing too late move the stator plate counter clockwise.

To time the PTO side cylinder insert the dial indicator in PTO spark plug hole. Turn the engine over clockwise and bring the PTO piston up to TDC. Zero the gauge. Hook up the buzz box to the blue /red wires. Turn the engine over counter clockwise and note the firing position. It should be .077 BTDC. If the points are firing too early decrease the point gap on the PTO set of points. If the points are firing too late increase the point gap on the PTO side points.

For installation of points, and condensers refer to section L - 07.

NOTE: The mag set of points are the top set, the PTO points are the bottom set with the spark plugs facing up.

With the timing properly set apply a bit of grease to the phenolic block for proper lubrication of the point arms.


Before installing the magneto run a business card or similar item through the points when they are closed to remove any grease or foreign material.

Reassembly -Rotary valve timing.

Tools Required.
Dial Indicator
13 mm socket

Shop supplies


..With the dial indicator installed in the magneto cylinder bring the piston to TDC. Carefully unwrap your rotary valve. Lightly oil it. Install the rotary valve disk onto the splines on the rotary valve shaft so the lip of the valve cut out is as close to the intake opening on the PTO side cylinder as possible, and the other valve cut out lines up with the mark on the upper crankcase half. The valve is asymmetrical, so if one side doesn't appear to be close enough flip it over and try the other side.

With the valve properly installed, check to make sure that the rubber sealing ring is in place on the rotary valve plate, then install the plate. Install the two lower bolts finger tight.


There are two lengths of bolts, the longer bolts are used in the top two holes to retain the bottom of the rotary valve tank bracket. The installation of bolts other than those for this area of the engine can result in extensive damage to the crankcase half.

With magneto piston at top dead centre, the rotary valve disk should be as close to the intake opening as possible. Try disk one way then the other, for closest fit.

Reassembly - Rotary valve bracket and tank.

Tools Required.
Blade screw driver
13 mm socket
10 mm deep reach thin walled socket

Reconnect the wiring, to the two coils, ignition suppressor box, and ground wire. The coils are wired inversely that is one coil is wired with the ground wire going to the number 1 pole on the coil while on the other coil the ground goes to the number 15 pole. (Refer to fig b section M -03 for correct wiring). Incorrect wiring can result in a high speed miss. Also note that the ignition suppressor box is wired black to red and red to black incorrect wiring can result in no spark. Reconnect your two rotary valve tank hoses (refer to fig For proper hose installation) and tighten the hose clamps. If the water outlet has been removed, reinstall the sealing ring, and then the water outlet. Slip the tank bracket into place, over top of the two head studs, install the two flat washers, lock washer and 10mm nuts. Now install the two 13 mm bolts lock washer and flat washers into the bottom of the bracket, and through the top two holes in the rotary valve plate.

With all the nuts and bolts snug torque to proper specifications.

Reassembly -Recoil cup, and recoil assembly

Tools Required.
10 mm socket/6 mm allen wrench
torque wrench
13 mm socket
crankshaft locking pin

Shop supplies.
Loctite Blue 242


.Using a 6 mm allen wrench/13 mm socket install your recoil cup, and three retaining bolts and lock washers, prior to installation apply Loctite to the threads of the three bolts. Using the locking pin supplied in the Rotax tool kit lock the crankshaft up, and torque the 3 bolts/screws in three stages to specification.

With the recoil cup in place install your recoil. Install the 4, 10 mm bolts and lock washers or 6mm allen screws and lock washers, which ever your engine has, and torque to specifications

Carburetor Installation

Tools Required.
Philips screw driver


Using a Phillips screw driver reinstall the carburetors into the two rubber intake flanges. Ensure the carburetors are level, tighten the two clamps.

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