Ever since I have owned my TA, when out driving every now and again I would get the smell of engine oil burning on the exhaust. On inspection of the exhaust front down pipe I could see oil marks and crust from burnt oil. The culprit is the clutch operating arm.
The TA cork clutch runs in oil. The flywheel teeth throw the oil from the small sump in the base of the clutch housing up into the housing where there is an outlet port to return oil to the engine sump. As a consequence of this, the clutch operating fork and shaft are always covered in oil.
The clutch operating shaft just runs in a 5/8th inch line bored hole in the cast alloy bell-housing. This shaft operates a large thrust bearing ball race to pull the clutch pressure plate backwards when the clutch pedal is depressed. Consequently there is always some wear in the bell-housing clutch shaft hole, and this is where the oil exits, then drips down onto the exhaust front pipe directly beneath.
As I had taken my engine out to do a precautionary clutch plate change before going to the Scottish Highlands in the summer, now was the time to solve the problem. I took the bell-housing to my local engineering shop and asked him to bore out the near side clutch shaft exit hole to a diameter of 22mm to a depth of 3 mm (see photo 1).
With the engine back in the car, and before I fitted the reconditioned cylinder head (see TTT 2 issue 17) I got my dial gauge out to check the TDC (top dead centre) marks on my timing case housing and crank pulley. They were spot on, but when checking the ignition timing you cannot see these marks easily because the radiator is in front of the markings. You can only see from the side and introduce a bit of error due to parallax. I had made a small timing pointer to fit via two of the small bolts on the timing case oil seal housing (see photo 3), so this was fitted on the passenger side of the engine.
With TDC established I made a new mark on the crank pulley to line up with the new pointer, and painted both marks with white paint. I also made a new mark that equates to 5 degrees BTDC. On a TA the crank pulley is 11cm in diameter, so 110 x 3.142 divided by 360 then multiplied by 5 comes to 4.8 mm. The new mark on my crank pulley was cut 5mm (nearest I could measure) before TDC. I tend to run my TA with a static setting of around 5 to 7 degrees before TDC. It is quite nice when using my stroboscopic timing light to be able to see the marks accurately and adjust the distributor easily from the same side of the car.
Brian Rainbow
