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  6. Curing Oil Leaks

Leaks through slots where rockers protrude :— Clean disc Valve K136, and see that it works freely. Renew felt washers on rocker pins. If the above remedies are not effective it is best to send the Cambox to the Works for attention to the large Bronze bearing.

Leaks from the large flange face on bevel gear box :— The joint here is metal to metal, and therefore the slightest bit of dirt will cause a leak. Grinding in the bronze bearing on to the face of the bevel gear box with fine grinding paste will correct any trouble. See that a very small space exists all round the outer flange thus ensuring that the bronze bearing is clamped up between the two aluminium parts. See that all screws are tightened up equally. A little liquid packing is useful such as gold size when applied to the surfaces.

Leaks from bevel gear bushes :— Look to the packing washer under flange. Never use a washer thicker than the original or it will alter the meshing of the bevel gears.

Gland Nuts of vertical shaft cover Make sure that they are not too tight on their threads or that they are not tight up against the end of thread. If so, add more packing asbestos string or similar material. Six or seven turns around the vertical shaft cover of 1/16" string is sufficient. See that the wire jump ring is in position, in its notch at the bottom of the tube, or the tube will slip down. Very serious oil leaks from most joints will occur if the oil tank vent pipe is allowed to become stopped up. This causes a pressure on the oil in the tank and causes oil to be pressure-fed to the oil pump. The oil should reach the pump by gravity only.

Cylinder Head Joint :— This is a ground joint, and the joint proper is made on the narrow edge, there should be a suspicion of clearance all around the broad face to enable the bolts to pull head down to the narrow edge. The correct clearance can be obtained by grinding the narrow edge with fine grinding powder and the broad face at the same time with coarse. The coarse gives the slight extra clearance required. Care is necessary when tightening up the bolts to ensure an equal pressure on all and each one should be tightened a little at a time when nearly home.

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  • Velocette Documents
    • GTP Manuals
      • F40/5R GTP Instruction Book 1951
    • KSS, KTS Manuals
      • F236/4R Mk. II OHC Instruction Book 1950
      • F42/3R OHC Models 1925-1931 Instruction Book
    • MAC Manuals
      • F469/4R MAC Service Guide 1965
      • F466/2R MAC Owner's Handbook 1955
      • F50/7R MAC Rigid Frame Service Manual 1955
      • F50/4R Supplement
    • MOV and MAC
      • F131-3R Instruction Book 1937
    • MSS Manuals
      • F477 Owners Handbook 1954
    • Venom, Viper, MSS
      • F485/1R Owner's Handbook 1956
      • F484/9R Service Guide 1967
      • F484/11R Service Guide 1971
    • Valiant Manuals
      • F62-1R Service Manual