Page 193 - CTS - Mechanic Diesel - TP

MECHANIC DIESEL - CITS

• Check the magneto coils for open and short circuit with the help of an AVO meter. If found damaged replace
the coil with a new one.
Assembling the magneto assembly

• Refit coils and tighten the screws.
• Fix CB point assembly with its screws firmly. base and tighten mounting
• Fix the ignition cam ring on the flywheel hub (extended and lock it.
• Assemble the counterweights with tension spring inter posed on its lugs.
• Insert the counterweights (8) with spring (7) and place on the starter plate.
• Place the starter plate with the flange in its position are screw the bolts firmly.

• Connect the wires in the junction box.
• Connect the clamping plate with screws.
• Fix the flywheel by tapping with a mallet (wooden) so that it can be fitted properly. Ensure that the key is fitted
in its groove.
• Place the spring washer and lock-nut in their position.
• Tighten the lock-nut in anticlockwise direction by locking the flywheel using a flywheel holding down tool. Fix
the circlip in its position. Place the magneto cover and tighten it with screws.
• Fix the junction box and connect the wires.
• Fix the dust cap and lock with a circlip.
• Fit the magneto cover and lock it with screws.
• Crank the engine crankshaft and test for spark.

Setting the gap
• Remove the magneto distributor cover and rotor.
• Rotate the engine crankshaft until the ignition cam is in the position of giving maximum opening of the contacts.
• Observe the tip of the fibre piece of CB points assembly resting on the toe (highest point) of the cam.
• Insert the feeler blade of recommended thickness and measure the points gap.

• If not, adjust the gap as below.
• Slacken the CB points gap adjusting screw (small screw) and move the fixed contact plate by inserting the
screwdriver in the slot and twist in a clockwise or anticlockwise direction and then finally lock the screw

• Once again check the gap with a feeler blade of specified thickness.
Setting the timing
• Remove the spark plug (use a plug spanner
• Turn the engine crankshaft and bring the piston to TDC of compression stroke.
• Observe the timing marks at the flywheel housing and base plate of magnets (use a hand lamp if not visible)

• Turn the engine once again slowly and align the timing mark on flywheel with mark on flywheel housing.
• Observe the CB joints whether they are in just opening position. (Note: The fibre tip should rest on the releasing
face of the cam.)

• Make sure that the exact point of opening of CB points by the tip of the screwdriver. (If it is open, there will be
a spark.)
• Refix the spark plug. Connect the ignition timing light

• Start the engine
• Pass the light on timing marls Ensure the timing marks coincide with each other. If not adjust the CB points and
recheck it.

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CITS : Automotive - Mechanic Diesel - Exercise 11.1