PIAGGIO Beverly 300ie - Service manual > Removing the cylinder head

• Undo the two screws "1" fixing the head to the transmission-side crankcase half.
• Unscrew the four nuts "2" by loosening them in two or three stages and in a crossed sequence.

• Remove the head.

N.B.

IF NEEDED, THE HEAD MAY BE REMOVED WITH THE CAMSHAFT, ROCKER PINS AND FIXING BRACKET. THE HEAD CAN ALSO BE REMOVED WITHOUT REMOVING THE CHAIN AND THE CRANKSHAFT CHAIN TENSIONER.

• Remove the gasket.

Removing the valves

• Using the appropriate tool fitted with an adaptor, remove the cotters, caps, springs and valves.
• Remove the oil guards with the appropriate tool.
• Remove the lower spring supports.

CAUTION

REPLACE THE VALVES IN SUCH A WAY AS TO RECOGNISE THEIR ORIGINAL POSITION ON THE HEAD.

Specific tooling
  020382Y011 adapter for valve removal tool
  020382Y Valve cotters equipped with part 012 removal tool
  020431Y Valve oil seal extractor

Removing the cylinder - piston assy.

• Remove the chain guide slider; be careful with the two alignment dowels and remove the cylinder.

• Remove the base gasket; be careful with the two centring dowels and the dowel pin.

• Remove the sealing rings, the pin and remove the piston.

CAUTION

TO PREVENT DAMAGING THE PISTON, SUPPORT IT WHILE REMOVING THE CYLINDER.

N.B.

BE CAREFUL NOT TO DAMAGE THE SEALING RINGS DURING REMOVAL.

Inspecting the small end

N.B.

TO MEASURE WEAR LIMITS AND COUPLING CLEARANCES, SEE THE SPECIFICATIONS CHAPTER.

See also
Crankcase - crankshaft - connecting rod

Inspecting the wrist pin

N.B.

TO MEASURE WEAR LIMITS AND COUPLING CLEARANCES, SEE THE SPECIFICATIONS CHAPTER.

See also
Cylinder - piston assy.

Inspecting the piston

N.B.

TO MEASURE WEAR LIMITS AND COUPLING CLEARANCES, SEE THE SPECIFICATIONS CHAPTER.

See also
Cylinder - piston assy.

Inspecting the piston rings

N.B.

TO MEASURE WEAR LIMITS AND COUPLING CLEARANCES, SEE THE SPECIFICATIONS CHAPTER.

See also
Piston rings

Removing the piston

• Install piston and wrist pin onto the connecting rod, aligning the piston arrow the arrow facing towards the exhaust.

• Fit the pin retainer ring onto the appropriate tool
• With opening in the position indicated on the tool

S = left
D= right

• Place the wrist pin retainer ring into position using a punch
• Fit the wrist pin retainer ring using the plug as shown in the figure

N.B.

THE TOOL FOR INSTALLING THE RETAINER RINGS MUST BE USED MANUALLY.

CAUTION

USING A HAMMER MIGHT DAMAGE THE STOPS' HOUSING.

Specific tooling
  020430Y Pin lock fitting tool

Choosing the gasket

• Provisionally fit the piston into the cylinder, without any base gasket.
• Install a dial gauge on the special tool using the short union, as shown in the figure.

Specific tooling
  020475Y Piston position checking tool

• Using an abutment plane, reset the dial gauge with a preload of a few millimetres.
• Finally fix the dial gauge.
• Check the perfect sliding of the feeler pin.
• Install the tool on the cylinder without changing the dial gauge position.
• Lock the tool using the original head fixing nuts.
• Rotate the crankshaft up to the TDC (the inversion point of the dial gauge rotation)
• Measure the deviation from the reset value.

• By means of the table, see the Specifications chapter identify the cylinder base gasket thickness to be used for refitting. Correctly identify the cylinder base gasket thickness to keep the correct compression ratio.
• Remove the special tool and the cylinder.

N.B.

IF DEVIATIONS (OR RECESSES OR PROJECTIONS) CLOSE TO THE CHANGE OF CATEGORY ARE MEASURED, REPEAT THE MEASUREMENT AT THE OPPOSED SIDE. TO DO SO, REPEAT THE TOOL INSTALLATION BY INVERTING ITS POSITION.

See also
Slot packing system

Refitting the piston rings

• Pistons (like cylinders) are supplied in 4 categories: A, B, C and D, and must be fitted so that the reference arrow faces the exhaust duct. The letter is found at the centre of the piston.
• Fit the sealing rings with the word TOP or the identification letter facing upwards. In any case, the step must be facing opposite the piston crown.
• Sealing rings are manufactured with a cylinder contact conical cross-section and piston gaps must be offset by 120º in order to obtain a better bedding.
• Lubricate rings with engine oil when fitting them.

See also: