E Type 4.2 Timing.
Discussion
Hi Glenn,
The procedure for setting the timing on your 'E' is as follows; indeed this applies to all XK engines from the 120 up to the last of the Series 3 XJ saloons before the XJ40.
Strictly speaking, to carry this out correctly you first have to check the accuracy of the timing pointer position. If you look at it carefully on the front of the sump, you will see that it actually is a steel pointer mounted with slotted holes and can be adjusted laterally for a fine setting. To do this remove No 1 spark plug and mount a clock gauge on the head with the probe lightly contacting the piston crown and turn the engine very slowly to TDC. As you approach maximum stroke the reading will rise and then start to drop as the crank goes over TDC. Bring it back until you have the highest reading and this is the piston bang on TDC. You then slacken the two bolts, which are 7/16 AF, on the pointer and adjust it until the point aligns precisely with the mark on the crankshaft damper: you are then ready to set up your ignition.
Two things are critical here; the condition of the distributor, and the dwell angle setting.
Make sure there is no wear in the spindle and both the centrifugal and vacuum advances are operating correctly. It is very common on Es for the centrifugal to be seized through lack of oil on the felt pad inside the spindle head.
I will assume that your electronic ignition is contactless and therefore requires no dwell angle adjustment, but for others do NOT rely on a feeler gauge to set the points gap accurately; use a dwell meter for a final precise setting.
After you have the distributor correctly set up then the final task is to adjust the timing setting. Unfortunately on the E the easiest way is on a ramp with the bonnet open, simply because you can clip the timing light leads onto the battery and No 1 HT lead and run them down through the front frame to shine the light on the timing mark at the front of the sump. You can also reach the distributor from underneath to effect adjustment to advance or retard the timing if required. If you don't have access to a ramp then axle stands are the next best thing.
The most difficult Jaguar to set the timing on is the 240 model with a straight port head; this has the thermostat housing right over the top of the distributor and you have to set the points up with a mirror!!
Electronic ignition is the single best modification to carry out on an old Jaguar; it transforms the spark voltage, eliminates timing errors at high revs, and dramatically improves fuel consumption.
The procedure for setting the timing on your 'E' is as follows; indeed this applies to all XK engines from the 120 up to the last of the Series 3 XJ saloons before the XJ40.
Strictly speaking, to carry this out correctly you first have to check the accuracy of the timing pointer position. If you look at it carefully on the front of the sump, you will see that it actually is a steel pointer mounted with slotted holes and can be adjusted laterally for a fine setting. To do this remove No 1 spark plug and mount a clock gauge on the head with the probe lightly contacting the piston crown and turn the engine very slowly to TDC. As you approach maximum stroke the reading will rise and then start to drop as the crank goes over TDC. Bring it back until you have the highest reading and this is the piston bang on TDC. You then slacken the two bolts, which are 7/16 AF, on the pointer and adjust it until the point aligns precisely with the mark on the crankshaft damper: you are then ready to set up your ignition.
Two things are critical here; the condition of the distributor, and the dwell angle setting.
Make sure there is no wear in the spindle and both the centrifugal and vacuum advances are operating correctly. It is very common on Es for the centrifugal to be seized through lack of oil on the felt pad inside the spindle head.
I will assume that your electronic ignition is contactless and therefore requires no dwell angle adjustment, but for others do NOT rely on a feeler gauge to set the points gap accurately; use a dwell meter for a final precise setting.
After you have the distributor correctly set up then the final task is to adjust the timing setting. Unfortunately on the E the easiest way is on a ramp with the bonnet open, simply because you can clip the timing light leads onto the battery and No 1 HT lead and run them down through the front frame to shine the light on the timing mark at the front of the sump. You can also reach the distributor from underneath to effect adjustment to advance or retard the timing if required. If you don't have access to a ramp then axle stands are the next best thing.
The most difficult Jaguar to set the timing on is the 240 model with a straight port head; this has the thermostat housing right over the top of the distributor and you have to set the points up with a mirror!!
Electronic ignition is the single best modification to carry out on an old Jaguar; it transforms the spark voltage, eliminates timing errors at high revs, and dramatically improves fuel consumption.
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