Vespa GTS Super 300 ie - Service manual > Studs
Check that the stud bolts have not worked loose from their seat in the crankcase.
Check the depth of stud bolt driving with a gauge, as indicated in the picture. If it varies significantly from the driving depth indicated, it means that the stud bolt has yielded.
In this case, replace it.
By working on two fitted cylinder head fixing nuts, nut and lock nut, as shown in the picture, remove the stud bolt from its seat.
Clean the threaded seat on the carter thoroughly.
Refit a new stud bolt and apply the special product on the threading crankcase side.
Tighten up to the depth of the driving indicated.
Recommended products
Loctite Quick Set Loctite 270 high strength threadlock
Loctite 270 high strength threadlock
Lubrication
Conceptual diagrams
LUBRICATION CIRCUIT
Oil pressure check
- Remove the electrical minimum oil pressure switch connection and remove the switch.
- Check that the oil pressure reading is between 0.5 and 1.2 atm with the engine idling at 1650 rpm and the oil at the required temperature (wait for at least one electric ventilation).
- Check that the oil pressure is between 3.2 and 4.2 atm with the engine running at 6000 rpm and the oil at the required temperature.
- Remove the appropriate tools once the measurement is complete, refit the oil pressure switch and washer, tightening it to the specified torque and fit the flywheel cover.
- If the oil pressure is not within the specified limits, in the following order, check: the oil filter, the oil by-pass valve, the oil pump and the crankshaft seals.
N.B.
THE CHECK MUST BE CARRIED OUT WITH OIL AT THE CORRECT LEVEL AND WITH AN OIL FILTER IN PROPER CONDITION.
Characteristic
Oil pressure
Minimum pressure admitted at 6000 rpm: 3.2 atm.
Locking torques (N*m)
Minimum oil pressure sensor 12 to 14
See also:
Vespa GTS Super 300 ie - Service manual > Splitting the crankcase halves
Before opening the crankcase, it is advisable to check the axial clearance of the crankshaft. To do this, use a plate and a support with appropriate tool dial gauge. Upper clearances are an indication of wear on the surfaces of the crankshaft casing support. Remove the 10 crankshaft coupling screws. Separate the crankcase while keeping the crankshaft in one of the two halves of the crankcase. Remove the crankshaft. Remove the half crankcase coupling gasket. Remove the two screws and the internal cover shown in the diagram. Remove the oil guard on the flywheel side. Remove the oil filter fitting shown in the diagram. Check the axial clearance on the connecting rod. Check the radial clearance on the connecting rod. Check the surfaces that limit the axial free-play are not scored and measure the width of the crankshaft between these surfaces, as shown in the diagram. If the axial clearance between crankshaft and crankcase is exceeding and the crankshaft does not have any defect, the problem must be due to either excessive wear or wrong machining on the crankcase. Check the diameters of both the bearings of the crankshaft in accordance with the axes and surfaces shown in the figure. The half-shafts are classified in two categories Cat. 1 and Cat. 2 as shown the chart below.
Vespa GTS Super 300 ie - Service manual > Crankshaft oil seals
Removal Remove the transmission cover and the complete drive pulley beforehand Install the base of the appropriate tool on the oil seal using the screws provided.
