Lotus Service Bulletin

Class	111
Number	1971/07
Type	Twin-Cam Engines
Date	11.1.1971

Title:	Exhaust Emission Carburetors Starter Housing.
Reason:	It has been found in Service that a number of carburetors have been fitted to vehicles with the choke settings weaker (leaner) than those originally tested (small holes in starter disc) which may contribute to poor cold starting.
Charges:	U . K. - Warranty EXPORT - Factory - Distributor	NO NO NO
Action:	Where complaints are received of difficult cold starting and all other conditions (ignition timing, sparking plugs, etc.) have been checked and found satisfactory, then the following action is recommended. Release the choke cable and remove the starter housing assembly from the front carburetor. Using the shank of the appropriate drill, check that the progression holes in the starter disc are to the following specification:- - 1st. hole = .40mm - 2nd.hole = .60mm - 3rd, hole = .80mm - 4th. hole = 1.00mm If the holes are not to this specification, they should be drilled out as follows: Remove the starter disc as an assembly from the starter housing assembly, by releasing the nut securing the fast idle lever to the housing. Remove the circlip and spring holding the halves of the disc together. The outer side of the disc halves is held by the staked end of the shaft. Allow the halves of the disc to part, then using the appropriate drill with soft grease in its flutes, rotate the drill between the fingers. Care must be taken during this operation that the holes are not elongated. After drilling, replace all parts by reversing the removal procedure. NOTE: We are also taking this opportunity to clarify why LOTUS only have one choke. During starting and part throttle openings, all mixture from both carburetors passes through one cross-over pipe only, therefore one choke can supply all four cylinders.