Category Archives: Engine Bay

MKI Ignition Coil Bracket

Contributor: F. Navest

Originally the LUCAS ignition coil was located very close to the distributor on a bracket that was attached to the engine support.  This bracket was exclusively applied for the Mk1 MGB, 3 synchro cars built form ’62 till October 1967.  This bracket was removed during the design of  the Mk2 to allow future   simplification of maintenance.



Early MGB Lucas Sparkplug caps, cables

Contributor: F. Navest

The original LUCAS 78106A sparkplug caps were original wear on 3 synchro cars, (i.e. during the production of the 18GA & 18 GB engines). They do, on the other hand, cause radio interference that was difficult to suppress properly. The technology involved with these plugs and cables was outclassed.

The state of art technology in 1967 meant that the copper core cables had to be replaced by silicone cables, which have a degree of  internal resistance that surpasses the interference to radio and TV equipment.


These early 60’s  Solid copper core High Tension cables in combination with LUCAS side entry distributor caps and LUCAS sparkplug caps last forever, however. I am not sure how long the Ignition Lead Spacer and yellow identity markers were maintained. I have the impression that the Spacer as discontinued in 1967, whereas the markers were probably continued till 1969.





Ignition System Vacuum Pipe

Author: M. Feig w/Assistance from A. Henderson
In the past, a lot of questions have been asked relative to how this vapour seperator should be mounted.  It is difficult to see from the Carburator side as it bolts to the 2nd from the back manifold bolt, and then it has a clamp at the rear head bolt, and then down and around to the distributor.  Another reason for this article is to point ot that many of the engine components were not painted seperately prior to being assembled.  In fact, this is a prime example of a component that was assembled and then painted at the same time the engine was painted.

Vacuum Control pipe1

Note how engineside was not painted:

Vacuum Control pipe2


and then pipe attaches to vacuum portion of the 25D distributor (hard to see here)



Early MGB Identification Tag Appearance and Location

Author: A. Henderson

The early B up until mid-1966? used a body tag and a VIN tag.  The rectangular aluminum alloy serial tag is fastened with 2 posidrive self tapping screws to the right inner fender in front of the radiator and will have a series of digits beginning, on roadsters with GHN3, followed by a series of numbers which are the actual car ID number.  North American left hand drive cars will have a “L” after the 3 and preceding the actual number.  .
The body number tag is screwed to the right inner fender parallel with the carburetors and is held by 2 small slot headed screws.  It begins with MGB….followed by a series of numerals.
Reputedly some cars for some markets may have the VIN number stamped on a tab near the right motor mount on the right frame rail.   This stamped VIN may or may not be present, and when present is often stamped very lightly, making locating and/or reading it quite difficult.
MVC-035S MVC-036S



Early MGB Brake and Clutch Master Cylinder Caps

Author: A. Henderson

The early MGB had steel/tin caps on the Lockheed brake and clutch master cylinders.  Later MGBs utilized a white “nylon” plastic cap.  These later caps will fit the earlier cylinders.  It is also not uncommon to find caps from solvent cans used, as they were very close in fit and appearance, without the slot across the top of the cap.  These caps were also used on the MGA and probably other Lockheed cylinders of the same time.  Apparently a company specializing in MGA parts is undergoing the remanufacture of these caps, but at writing these are not available.
MVC-034S MVC-037S


Valve Cover Venting MGB18G Engine

Author: A. Henderson

These engines used on 1962 and 1963 cars did not have a PCV Valve.   Crankcase pressure was vented through a road draft tube from the front tappet cover, and through this simple rubber hose connecting the valve cover to a port on the front air filter backing plate.  Vaccuum created by the carburetors pulling air into the engine pulled vapour from the valve cover/crankcase.  The air filter backing plate for this application is unavailable, as is the valve cover itself.


Retaining Bracket – Oil Gauge Pipe

Author: M. Feig with assitance from T. Aczel
This early MGB Bracket rested on the shelf under the heater and its purpose was to prevent the fitting from turning and snapping off the little copper line.  I am unsure of the changeover date but this bracket was eliminated from production when it was determined to be unnecessary. 

Refer to B.M.C. Service Parts List (AKD3227) (11/63) Plate “O” AHH 6938

OLYMPUS DIGITAL CAMERARetaining Bracket-Oil guage pipe